Patent Publication Number: US-2022226077-A1

Title: Dental appliances and associated systems and methods of use

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 15/929,443, filed May 2, 2020, which claims to U.S. Provisional Patent Application No. 62/842,391, filed May 2, 2019, and U.S. Provisional Patent Application No. 62/956,290, filed Jan. 1, 2020, the disclosures of which are incorporated herein by reference in their entireties. 
     This application is also related to the following applications, each of which is hereby incorporated by reference in its entirety: U.S. patent application Ser. No. 16/865,323, titled DENTAL APPLIANCES, SYSTEMS AND METHODS, filed May 2, 2020; International Patent Application No. PCT/US20/31211, titled DENTAL APPLIANCES, SYSTEMS AND METHODS, filed May 2, 2020; U.S. patent application Ser. No. 15/929,444, titled DENTAL APPLIANCES AND ASSOCIATED SYSTEMS AND METHODS OF USE, May 2, 2020; U.S. Patent Application No. PCT/US20/70017, titled DENTAL APPLIANCES AND ASSOCIATED SYSTEMS AND METHODS OF USE, filed May 2, 2020; U.S. patent application Ser. No. 15/929,442, titled DENTAL APPLIANCES AND ASSOCIATED METHODS OF MANUFACTURING, filed May 2, 2020; and International Application No. PCT/US20/70016, titled DENTAL APPLIANCES AND ASSOCIATED METHODS OF MANUFACTURING, filed May 2, 2020. 
    
    
     TECHNICAL FIELD 
     The present technology relates to the field of orthodontics and, more particularly, to devices, systems, and methods for securing orthodontic appliances to a patient&#39;s teeth. 
     BACKGROUND 
     A common objective in orthodontics is to move a patient&#39;s teeth to positions where the teeth function optimally and aesthetically. To move the teeth, the orthodontist begins by obtaining multiple scans and/or impressions of the patient&#39;s teeth to determine a series of corrective paths between the initial positions of the teeth and the desired ending positions. The orthodontist then fits the patient to one of two main appliance types: braces or aligners. 
     Traditional braces consist of brackets and an archwire placed across a front side of the teeth, with elastic ties or ligature wires to secure the archwire to the brackets. In some cases self-ligating brackets may be used in lieu of ties or wires. The shape and stiffness of the archwire as well as the archwire-bracket interaction governs the forces applied to the teeth and thus the direction and degree of tooth movement. To exert a desired force on the teeth, the orthodontist often manually bends the archwire. The orthodontist monitors the patient&#39;s progress through regular appointments, during which the orthodontist visually assesses the progress of the treatment and makes manual adjustments to the archwire (such as new bends) and/or replaces or repositions brackets. The adjustment process is both time consuming and tedious for the patient and more often than not results in patient discomfort for several days following the appointment. Moreover, braces are not aesthetically pleasing and make brushing, flossing, and other dental hygiene procedures difficult. 
     Aligners comprise clear, removable, polymeric shells having cavities shaped to receive and reposition teeth to produce a final tooth arrangement. Dubbed “invisible braces,” aligners offer patients significantly improved aesthetics over braces. Aligners do not require the orthodontists to bend wires or reposition brackets and are generally more comfortable than braces. However, unlike braces, aligners cannot effectively treat all malocclusions. Certain tooth repositioning steps, such as extrusion, translation, and certain rotations, can be difficult or impossible to achieve with aligners. Moreover, because the aligners are removable, success of treatment is highly dependent on patient compliance, which can be unpredictable and inconsistent. 
     Lingual braces are an alternative to aligners and traditional (buccal) braces and have been gaining popularity in recent years. Two examples of existing lingual braces are the Incognito™ Appliance System (3M United States) and INBRACE® (Swift Health Systems, Irvine, Calif., USA), each of which consists of brackets and an archwire placed on the lingual, or tongue side, of the teeth. In contrast to traditional braces, lingual braces are virtually invisible, and, unlike aligners, lingual braces are fixed to the patient&#39;s teeth and force compliance. These existing lingual technologies, however, also come with several disadvantages. Most notably, conventional lingual appliances still rely on a bracket-archwire system to move the teeth, thus requiring multiple office visits and painful adjustments. For example, lingual technologies have a relatively short inter-bracket distance, which generally makes compliance of the archwire stiffer. As a result, the overall lingual appliance is more sensitive to archwire adjustments and causes more pain for the patient. Moreover, the lingual surfaces of the appliance can irritate the tongue and impact speech, and make the appliance difficult to clean. 
     Therefore, a need exists for improved orthodontic appliances. 
     SUMMARY 
     The subject technology is illustrated, for example, according to various aspects described below, including with reference to  FIGS. 1A-134 . Various examples of aspects of the subject technology are described as numbered clauses (1, 2, 3, etc.) for convenience. These are provided as examples and do not limit the subject technology. 
     1. An appliance for installing on a patient&#39;s teeth, the appliance comprising:
         at least one first rigid segment having a length dimension, and at least one second rigid segment having a length dimension, wherein each of the first and second rigid segments is configured to extend along two or more adjacent teeth in a jaw of the patient when the appliance is installed;   at least one arm extending from the at least one first rigid segment; at least one loop or curved feature formed along the length dimension of the second segment; and   a plurality of bracket connectors, each bracket connector configured to selectively connect to a bracket that may be secured to respective one of the patient&#39;s teeth, the plurality of bracket connectors including at least one first bracket connector on the at least one arm and at least one second bracket connector on the at least one second rigid segment.       

     2. The appliance of Clause 1, wherein the first and second rigid segments are configured to extend along the same two or more adjacent teeth in the jaw of the patient when the appliance is installed. 
     3. The appliance of Clause 1, wherein the at least one first rigid segment is configured to extend along a different set of two or more adjacent teeth in the jaw of the patient relative to the teeth that the at least one second rigid segment is configured to extend along, when the appliance is installed. 
     4. The appliance of Clause 1, wherein at least a portion of the first segment comprises an arch shaped member having an arch shape or partial arch shape and configured to extend along two or more adjacent teeth in the patient&#39;s jaw. 
     5. The appliance of Clause 4, wherein the at least one arm comprises a first arm extending from the first rigid segment to a first one of the first bracket connectors, and a second arm extending from the first rigid segment to a second one of the first bracket connectors, and wherein the at least one second rigid segment extends from the first one of the first bracket connectors to the second one of the first bracket connectors. 
     6. The appliance of Clause 5, wherein the at least one second bracket connector comprises a plurality of second bracket connectors located along the at least one second rigid segment, between the first one of the first bracket connectors to the second one of the first bracket connectors. 
     7. The appliance of Clause 6, wherein the at least one first bracket connector comprises one or more further bracket connectors on the at least one first rigid segment. 
     8. The appliance of Clause 4, wherein each of the first arm and the second arm includes a spring member. 
     9. The appliance of Clause 4, wherein the at least one second rigid segment has a length dimension extending from one end of the arch shaped member of the first rigid segment. 
     10. The appliance of Clause 9, wherein the at least one arm extending from the at least one first rigid segment comprises a plurality of arms, the at least one first bracket connector comprises a plurality of first bracket connectors on the plurality of arms, and the at least one second bracket connectors comprise a plurality of bracket connectors along the length dimension of the second rigid segment. 
     11. The appliance of Clause 9, wherein the at least one second rigid segment comprises has a length dimension extending from a second end of the arch shaped member of the first rigid segment. 
     12. The appliance of Clause 11, wherein the at least one arm extending from the at least one first rigid segment comprises a plurality of arms, the at least one first bracket connector comprises a plurality of first bracket connectors on the plurality of arms, and the at least one second bracket connectors comprise a plurality of bracket connectors along the length dimension each of the second rigid segments. 
     13. The appliance of Clause 1, wherein the at least one arm comprises a first arm extending from the first rigid segment to a first one of the first bracket connectors, and a second arm extending from the first rigid segment to a second one of the first bracket connectors, and wherein the at least one second rigid segment extends from the first one of the first bracket connectors to the second one of the first bracket connectors. 
     14. The appliance of Clause 13, wherein the at least one arm comprises at least one additional arm located along the length of the first rigid segment between the first arm and the second arm, each additional arm extending from the first rigid segment to a respective further one of the first bracket connectors located between the first one of the first bracket connectors and the second one of the second bracket connectors. 
     15. The appliance of Clause 1, wherein at least a portion of the second rigid segment comprises an arch shaped member having an arch shape or partial arch shape and configured to extend along two or more adjacent teeth in the patient&#39;s jaw. 
     16. The appliance of Clause 1, wherein the appliance is configured as single, unitary structure from a single sheet of material. 
     17. An appliance for installing on a patient&#39;s teeth, the appliance comprising:
         at least one first rigid segment having a length dimension, and at least one second rigid segment having a length dimension, wherein at least one of the first and second rigid segments is configured to extend along two or more adjacent teeth in a jaw of the patient when the appliance is installed;   at least one arm extending from the at least one first rigid segment;   at least one loop or curved feature formed along the length dimension of the second rigid segment; and a plurality of bracket connectors, each bracket connector configured to selectively connect to a bracket that may be secured to respective one of the patient&#39;s teeth, the bracket connectors being provided along the length dimension of the second rigid segment, the bracket connectors including at least one bracket connector connected to the at least one arm extending from the at least one first rigid segment.       

     18. The appliance of Clause 17, wherein the at least one arm includes a spring member located between the at least one first rigid segment and the bracket connector to which the at least one arm is connected. 
     19. The appliance of Clause 17, wherein two or more of the bracket connectors are connected to two or more of the arms extending from the at least one first rigid segment. 
     20. The appliance of Clause 18, wherein each of the two or more of the arms includes a spring member located between the at least one first rigid segment and the bracket connector to which the arm is connected. 
     21. An orthodontic appliance, comprising:
         an anchor configured to be positioned adjacent a patient&#39;s teeth; and   an arm extending away from and coupled to the anchor, the arm including a first end portion at the anchor and a second end portion configured to be coupled to a securing member adhered to a tooth of the patient, wherein the second end portion comprises a first region and a second region extending from the first region at an angle, the first region being farther from the anchor than the second region,   wherein, when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is secured to the securing member, (a) the second region extends in a generally mesial-distal direction and abuts a coupling arm of the securing member, and (b) the first region abuts a portion of the coupling arm, thereby inhibiting rotation of the second end portion relative to the securing member.       

     22. The appliance of Clause 1, wherein, when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is secured to the securing member, the first region extends in a generally occlusal-gingival direction. 
     23. The appliance of any one of the Clauses herein, wherein, when the appliance is positioned adjacent the patient&#39;s teeth, the second region extends in a generally mesial-distal direction under the coupling arm of the securing member. 
     24. The appliance of any one of the Clauses herein, wherein, when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is secured to the securing member, the first region inhibits translation of the second end portion relative to the securing member. 
     25. The appliance of any one of the Clauses herein, wherein:
         the second end portion further comprises a third region closer to the anchor than the second region,   the portion of the coupling arm is a first portion of the coupling arm, and   when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is secured to the securing member, the third region extends in a generally occlusal-gingival direction and abuts a second portion of the coupling arm that is closer to the patient&#39;s gingiva than the second region of the second end portion.       

     26. The appliance of any one of the Clauses herein, wherein:
         the coupling arm is a first coupling arm and the securing member further comprises a second coupling arm,   the first region has a first side and a second side, and   when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is secured to the securing member, the first side of the first region abuts the first coupling arm and the second side of the first region abuts the second coupling arm such that the first region opposes mesial and distal rotation and/or translation relative to the securing member.       

     27. The appliance of any one of the Clauses herein, wherein:
         the second end portion of the arm further comprises a third region closer to the anchor than the second region,   the coupling arm is a first coupling arm and the securing member further comprises a second coupling arm, and   when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is secured to the securing member, the third region abuts a region of each of the first and second coupling arms that is closer to the root of the patient&#39;s tooth than a region of each of the first and second coupling arms that extends over the second region of the second end portion.       

     28. The appliance of Clause 26 or Clause 27, wherein, when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is secured to the securing member, the second region extends under both the first and second coupling arms in a generally mesial-distal direction. 
     29. The appliance of any one of the Clauses herein, wherein:
         the portion of the coupling arm is a first portion of the coupling arm,   the second end portion further comprises a third region extending from the second region toward the anchor, the third region having first and second legs, and   when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is secured to the securing member, one or both of the first and second legs of the third region abut a second portion of the coupling arm that is closer to the root of the patient&#39;s tooth than the first portion.       

     30. The appliance of Clause 29, further comprising a fourth region extending between the first and second legs, wherein the first and second legs, second region, and fourth region together define an opening. 
     31. The appliance of any one of the Clauses herein, wherein:
         the second end portion further comprises a third region extending from the second region, the third region being farther from the anchor than the second region, and   when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is secured to the securing member, the first region is adjacent a first side of the coupling arm and the third region is adjacent a second, opposing side of the coupling arm.       

     32. The appliance of Clause 31, wherein each of the first and third regions extends at an angle, relative to the second region, greater than 90°. 33. The appliance of Clause 31, further comprising a fourth region extending between the first and third regions, wherein the first, second, third, and fourth regions together define an opening. 
     34. The appliance of Clause 33, wherein:
         the portion of the coupling arm is a first portion of the coupling arm,   the appliance further comprises a fifth region extending from the second region toward the anchor, the fifth region having first and second legs,   when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is secured to the securing member, one or both of the first and second legs of the fifth region abut a second portion of the coupling arm that is closer to the root of the patient&#39;s tooth than the first portion.       

     35. The appliance of Clause 34, wherein:
         the opening is a first opening,   the appliance further comprises a sixth region extending between the first and second legs of the fifth region, and   the second, fifth, and sixth regions together define a second opening.       

     36. The appliance of any one of the Clauses herein, wherein the anchor is configured to be positioned adjacent a lingual side of the patient&#39;s teeth. 
     37. The appliance of any one of the Clauses herein, wherein the anchor is configured to be positioned adjacent a buccal side of the patient&#39;s teeth. 
     38. The appliance of any one of the Clauses herein, wherein the arm is one of a plurality of arms, each of the plurality of arms having a respective second end portion with first and second regions. 
     39. The appliance of any one of the Clauses herein, wherein the anchor and the arm are formed of a single, unitary member. 
     40. The appliance of any one of the Clauses herein, wherein the anchor and the arm are integral with one another. 
     41. The appliance of any one of the Clauses herein, wherein the anchor and the arm comprise a continuous surface. 
     42. The appliance of any one of the Clauses herein, wherein the angle is between 70°-110°. 43. The appliance of any one of the Clauses herein, wherein the anchor is arch-shaped. 
     44. The appliance of any one of the Clauses herein, wherein the anchor and the arm are formed of a superelastic material. 
     45. The appliance of any one of the Clauses herein, wherein the arm includes a biasing region between the first and second end portions, wherein the biasing region is configured to provide a rotational force and/or a longitudinal force to at least one of the patient&#39;s teeth when the second end portion is secured to the securing member. 
     46. The appliance of Clause 45, wherein the biasing region includes a serpentine shape. 
     47. The appliance of Clause 45, wherein the biasing region includes a first portion having a first inflection point and a second portion having a second inflection point, the second portion being farther from the anchor than the first portion. 
     48. The appliance of Clause 45, wherein the biasing region includes a first concave region facing a first direction, and a second concave region facing a second direction different than the first direction, the first concave region being farther from the anchor than the second concave region. 
     49. The appliance of any one of the Clauses herein, wherein the securing member is a 2D® lingual bracket. 
     50. The appliance of any one of the Clauses herein, wherein at least one of the anchor, the arm, or the securing member comprises nitinol, stainless steel, beta-titanium, cobalt chrome, other metal alloys, polymers, ceramics, and/or combinations thereof. 
     51. The appliance of any one of the Clauses herein, wherein the coupling arm of the securing member is bent over the second region of the second end portion. 
     52. The appliance of any one of the Clauses herein, wherein the coupling arm of the securing member is plastically deformed over the second region of the second end portion. 
     53. An orthodontic appliance, comprising:
         an anchor configured to be positioned adjacent a patient&#39;s teeth; and   an arm extending away from the anchor, the arm including a first end portion at the anchor and a second end portion configured to be coupled to a securing member adhered to a tooth of the patient, wherein the second end portion comprises an extension and first and second shoulder regions adjacent the extension;   wherein, when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is secured to the securing member, (a) the extension extends in a generally mesial-distal direction and abuts a coupling means of the securing member, and (b) the first and second shoulder regions abut mesial and distal sides of the coupling means, respectively, thereby inhibiting rotation and/or translation of the second end portion relative to the securing member.       

     54. The appliance of Clause 53, wherein, when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is secured to the securing member, the first region extends in a generally occlusal-gingival direction. 
     55. The appliance of any one of the Clauses herein, wherein the anchor is configured to be positioned on a lingual side of the patient&#39;s teeth. 
     56. The appliance of any one of the Clauses herein, wherein the anchor is configured to be positioned on a buccal side of the patient&#39;s teeth. 
     57. The appliance of any one of the Clauses herein, wherein the arm is one of a plurality of arms, each of the plurality of arms having a respective second end portion with respective first and second shoulder regions. 
     58. The appliance of any one of the Clauses herein, wherein the anchor and the arm are formed of a single, unitary member. 
     59. The appliance of any one of the Clauses herein, wherein the anchor and the arm are integral with one another. 
     60. The appliance of any one of the Clauses herein, wherein the anchor and the arm comprise a continuous surface. 
     61. The appliance of any one of the Clauses herein, wherein the anchor is arch-shaped. 
     62. The appliance of any one of the Clauses herein, wherein the anchor and the arm are formed of a superelastic material. 
     63. The appliance of any one of the Clauses herein, wherein at least one of the anchor, the arm, or the securing member comprises nitinol, stainless steel, beta-titanium, cobalt chrome, other metal alloys, polymers, ceramics, and/or combinations thereof. 
     64. The appliance of any one of the Clauses herein, wherein the arm includes a biasing region between the first and second end portions, wherein the biasing region is configured to provide a rotational force and/or longitudinal force to at least one of the patient&#39;s teeth when the distal portion is secured to the securing member. 
     65. The appliance of any one of the Clauses herein, wherein the securing member is a 2D® lingual bracket. 
     66. The appliance of any one of the Clauses herein, wherein the coupling arm of the securing member is bent over the second region of the distal portion. 
     67. The appliance of any one of the Clauses herein, wherein the coupling arm of the securing member is plastically deformed over the second region of the distal portion. 
     68. An orthodontic system, comprising:
         an anchor configured to be implanted adjacent a patient&#39;s teeth;   a plurality of arms coupled to the anchor and spaced apart from one another, the plurality of arms comprising a first arm including (i) an end portion, (ii) a first member at the end portion and extending in a first direction, and (iii) a second member at the end portion and extending from the first member in a second direction at an angle relative to the first member, the first member being farther from the anchor than the second member; and   a plurality of securing members configured to be disposed on the patient&#39;s teeth, the plurality of securing members comprising a first securing member including a coupling arm configured to secure the end portion of the first arm to the first securing member such that rotation and/or translation of the end portion relative to the first securing member is inhibited via the coupling arm.       

     69. The system of Clause 66, wherein, when the first arm is coupled to the first securing member, the first arm is generally oriented in an occlusal-gingival direction such that the end portion of the first arm is in apposition with a lingual face of at least one of the patient&#39;s teeth. 
     70. The system of any one of the Clauses herein, wherein the coupling arm is configured to be disposed over the second member and therein secure the first arm to the first securing member. 
     71. The system of any one of the Clauses herein, wherein the first securing member comprises a base attached to the coupling arm and configured to be fixed to a lingual face of one of the patient&#39;s teeth. 
     72. The system of Clause 71, wherein a portion of the coupling arm includes a curved surface, at least a portion of the curved surface being spaced apart from the base. 
     73. The system of any one of the Clauses herein, wherein the coupling arm is a first coupling arm, the system further comprising a second coupling arm, wherein, when the first arm is coupled to the first securing member, the first coupling arm is spaced apart from the second coupling arm via a base region of the end portion of the first arm. 
     74. The system of Clause 73, wherein the first coupling arm abuts a first side of the first member and the second coupling arm abuts a second side of the first member, the first side being opposite the second side. 
     75. The system of any one of the Clauses herein, wherein the first arm comprises a frame portion defining an opening and including the second member, a portion of the coupling arm being disposed within the opening when the first arm is coupled to the first securing member. 
     76. The system of any one of the Clauses herein, wherein the angle is within a range from 700 to 110°. 77. An orthodontic system, comprising:
         an anchor configured to be disposed adjacent a patient&#39;s teeth;   an arm coupled to and extending from the anchor, the arm comprising-a biasing portion, and
           an attachment portion extending from the biasing portion, the attachment portion including (i) a first member extending in a first direction and (ii) a second member extending in a second direction at an angle relative to the first member; and   
           a securing member configured to be attached to the patient&#39;s teeth, the securing members comprising a coupling arm configured to secure the attachment portion to the securing member such that rotation and/or translation of the attachment portion relative to the securing member is inhibited.       

     78. The system of Clause 77, wherein the first member is farther from the anchor than the second member. 
     79. The system of any one of the Clauses herein, wherein the anchor comprises an arch shape and is configured to be disposed on a lingual side of the patient&#39;s teeth. 
     80. The system of any one of the Clauses herein, wherein at least one of the anchor, the arm, or the securing member comprises nitinol, stainless steel, beta-titanium, cobalt chrome, other metal alloys, polymers, ceramics, and/or combinations thereof. 
     81. The system of any one of the Clauses herein, wherein the first direction is substantially orthogonal to the second direction. 
     82. The system of any one of the Clauses herein, wherein the coupling arm is attached to a base of the securing member and includes a coupling portion, wherein, when the attachment portion is coupled to the securing member, the coupling portion is disposed over the second member of the attachment portion to secure the attachment portion to the securing member. 
     83. The system of any one of the Clauses herein, wherein the arm comprises a frame portion defining an opening and including the second member, wherein, when the attachment portion is secured to the securing member, a portion of the coupling arm is disposed within the opening. 
     84. The system of any one of the Clauses herein, wherein, when the attachment portion is coupled to the securing member, the first member of the attachment portion is in apposition with or abuts the coupling arm. 
     85. The system of any one of the Clauses herein, wherein the arm comprises a third member extending in the second direction and is farther from the anchor than the second member, wherein, when the attachment portion is secured to the securing member, the third member abuts an end portion of the coupling arm. 
     86. The system of any one of the Clauses herein, wherein the arm comprises a third member extending in the first direction and is farther from the anchor than the second member, wherein the second member extends from the first member to the third member, and wherein, when the attachment portion is secured to the securing member, the coupling arm is between the first member and the third member. 
     87. The system of Clause 86, wherein the arm comprises a fourth member extending from the first member to the third member, the fourth member being farther from the anchor than the second member, wherein the first, second, third, and fourth members together define an opening, and wherein, when the attachment portion is secured to the securing member, a portion of the coupling arm is disposed within the opening. 
     88. A method for attaching an orthodontic appliance to a patient&#39;s tooth, the method comprising:
         providing an orthodontic appliance including—
           an anchor; and   an arm extending away from and coupled to the anchor, the arm including a first end portion at the anchor and a second end portion farther from the anchor than the first end portion, wherein the second end portion comprises a first region and a second region extending at an angle from the first region, the first region being farther from the anchor than the second region;   
           coupling a securing member to a patient&#39;s tooth; and   coupling the appliance to the securing member, thereby inhibiting rotation and/or translation of the second end portion relative to the securing member.       

     89. The method of Clause 88, wherein the securing member includes a coupling arm, and wherein coupling the appliance to the securing member comprises:
         positioning the second end portion of the appliance in apposition to the securing member such that the second region of the second end portion extends in a generally mesial-distal direction under the coupling arm of the securing member.       

     90. The method of Clause 89, wherein coupling the appliance to the securing member further comprises:
         before positioning the second end portion, temporarily moving a portion of the coupling arm to an open position, thereby enabling the second region to be positioned under the coupling arm.       

     91. The method of any one of the Clauses herein, wherein:
         the second end portion of the arm includes a base region extending from the second region of the second end portion toward the anchor,   the securing member includes a first coupling arm and a second coupling spaced apart from the first coupling arm, and   coupling the appliance to the securing member comprises—
           positioning the second end portion of the appliance in apposition to the securing member such that (i) the second region of the second end portion extends in a generally mesial-distal direction under each of the first and second coupling arms of the securing member, and (ii) the base region is between the first and second coupling arms.   
               

     92. The method of any one of the Clauses herein, wherein the appliance is that of any one of the Clauses herein. 
     93. An orthodontic appliance, comprising:
         a positioning member including a first portion shaped to resiliently receive a patient&#39;s teeth, and a second portion shaped to receive a bracket configured to be adhered to one of the patient&#39;s teeth, the second portion defining a channel positioned to receive a coupling arm of the bracket.       

     94. The appliance of Clause 93, wherein the second portion includes a first region extending in a first direction and a second region extending in a second direction different than or angled relative to the first region, the first and second regions at least partially defining the channel. 
     95. The appliance of any one of the Clauses herein, wherein, when the appliance is disposed over the patient&#39;s teeth, the first direction extends in a generally occlusal-gingival direction. 
     96. The appliance of any one of the Clauses herein, wherein, when the appliance is disposed over the patient&#39;s teeth, the second direction extends in a generally mesial-distal direction. 
     97. The appliance of any one of the Clauses herein, wherein the channel is one of two channels, and wherein the second portion includes a first region extending in a first direction between the two channels and a second region extending in a second direction different than the first direction, the first and second regions at least partially defining the two channels. 
     98. The appliance of any one of the Clauses herein, wherein the channel is a first channel, and wherein the second portion further defines a second channel spaced apart from the first channel, each of the first and second channels being positioned to receive a coupling arm of the bracket. 
     99. The appliance of any one of the Clauses herein, further comprising a third region peripheral to the first region and extending in the first direction. 
     100. The appliance of any one of the Clauses herein, wherein the channel is a first channel, the appliance further comprising (i) a second channel, and (ii) a fourth region peripheral to the first region and extending in the first direction, the first channel being positioned between the first and third regions and the second channel being between the first and fourth regions. 
     101. The appliance of any one of the Clauses herein, the second portion further comprising a bracket receiving portion disposed in the channel. 
     102. The appliance of any one of the Clauses herein, wherein the bracket receiving portion comprises a recess shaped to receive the coupling arm of the bracket or an end portion of the coupling arm. 
     103. The appliance of any one of the Clauses herein, wherein the bracket receiving portion extends from a base surface of the second portion by a first distance, and wherein an outermost surface of the second portion extends from the base surface by a second distance greater than the first distance. 
     104. The appliance of any one of the Clauses herein, wherein the second portion includes a first side and a second side generally opposite the first side, the bracket receiving portion being disposed on and/or facing the first side. 
     105. The appliance of any one of the Clauses, wherein:
         the second portion includes a first side and a second side generally opposite the first side, and   when the appliance is disposed over the patient&#39;s teeth, the first side at least partially faces a lingual direction and the second portion at least partially faces a buccal direction.       

     106. The appliance of any one of the Clauses, wherein the second side of the second portion includes a cavity to receive a base portion of the bracket, the coupling arm being fixed to the base portion. 
     107. The appliance of any one of the Clauses, wherein the second side of the second portion includes a cavity to receive a base of the bracket, the base being configured to be adhered directly to a lingual surface of the patient&#39;s teeth. 
     108. The appliance of any one of the Clauses herein, wherein the second portion protrudes from an outermost surface of the first portion. 
     109. The appliance of any one of the Clauses herein, wherein the first and second portions are integral with one another. 
     110. The appliance of any one of the Clauses herein, wherein the first and second portions comprise a single component. 
     111. The appliance of any one of the Clauses herein, wherein the first and second portions comprise a unitarily formed structure. 
     112. The appliance of any one of the Clauses herein, wherein the first and second portions comprise a continuous surface. 
     113. The appliance of any one of the Clauses herein, wherein the first and second portions comprise a polymer, plastic, or composite material. 
     114. The appliance of any one of the Clauses herein, wherein the first and second portions comprise a flexible, resilient, and/or non-rigid material. 
     115. The appliance of any one of the Clauses herein, wherein the positioning member is an aligner. 
     116. The appliance of any one of the Clauses herein, wherein the positioning member is configured to perform indirect bonding of a bracket. 
     117. The appliance of any one of the Clauses herein, wherein the positioning member is not configured to reposition a patient&#39;s teeth. 
     118. The appliance of any one of the Clauses herein, wherein the second portion, when disposed over the patient&#39;s teeth, generally has an orientation corresponding to an occlusal-gingival axis. 
     119. The appliance of any one of the Clauses herein, wherein, when the positioning member is disposed over the patient&#39;s teeth, the second portion is generally positioned adjacent or lingual to a lingual surface of one of the patient&#39;s teeth. 
     120. The appliance of any one of the Clauses herein, wherein the second portion of the positioning member is one of a plurality of second portions, each of the second portions corresponding to different ones of the patient&#39;s teeth. 
     121. The appliance of any one of the Clauses here, wherein the bracket is the securing member of any one of the Clauses herein. 
     122. The appliance of any one of the Clauses herein, wherein the first portion comprises a cavity to be disposed over the patient&#39;s teeth. 
     123. The appliance of any one of the Clauses herein, wherein the first portion comprises a plurality of individual cavities each configured to be disposed over one of the patient&#39;s teeth. 
     124. An orthodontic appliance, comprising:
         a positioning member including a first portion shaped to resiliently receive a patient&#39;s teeth, and a second portion shaped to receive a bracket to be adhered to one of the patient&#39;s teeth, the second portion including a first region extending in a first direction, and a second region extending in a second direction angled relative to the first direction, wherein the first and second regions in part define an area configured to receive a coupling arm.       

     125. The appliance of Clause 124, wherein the area is a first area on a first side of the first region and the coupling arm is a first coupling arm, and wherein the first and second regions in part define a second area on a second side of the first region configured to receive a second coupling arm. 
     126. The appliance of any one of the Clauses herein, wherein the first and second regions form a “T” shape. 
     127. A method for fixing one or more brackets to a patient&#39;s tooth using an orthodontic appliance, the method comprising:
         providing a positioning member including (i) a first portion shaped to resiliently receive a patient&#39;s teeth, and (ii) a second portion shaped to receive a bracket to be fixed to the patient&#39;s teeth, the second portion defining a channel;   positioning the bracket in the second portion; and   disposing the positioning member over the patient&#39;s teeth.       

     128. The method of Clause 127, wherein the positioning member comprises the positioning member of any one of the Clauses herein. 
     129. The method of any one of the Clauses herein, wherein disposing the positioning member over the patient&#39;s teeth comprises disposing the positioning member over the patient&#39;s teeth such that bracket in the second portion of the positioning member is adjacent a lingual surface of the patient&#39;s teeth. 
     130. The method of any one of the Clauses herein, further comprising, after disposing the positioning member over the patient&#39;s teeth, exposing the bracket to a light source thereby causing the bracket to adhere to the patient&#39;s teeth. 
     131. The method of any one of the Clauses herein, further comprising:
         after disposing the positioning member over the patient&#39;s teeth, exposing the bracket to a light source thereby causing the bracket to adhere to the patient&#39;s teeth; and   after exposing the bracket, removing the positioning member from the patient&#39;s teeth such that the bracket remains adhered to the patient&#39;s teeth.       

     132. The method of any one of the Clauses herein, wherein positioning the bracket in the second portion comprises sliding the bracket into the second portion such that a coupling arm of the bracket is received in a channel of the second portion. 
     133. The method of any one of the Clauses herein, wherein positioning the bracket in the second portion comprises sliding the bracket into the second portion such that a coupling arm of the bracket (i) is received in a channel of the second portion and (ii) is coupled to the positioning member. 
     134. The method of any one of the Clauses herein, wherein positioning the bracket in the second portion comprises coupling a coupling arm of the bracket to the positioning member. 
     135. The method of any one of the Clauses herein, wherein the second portion includes a bracket receiving portion having a recess, and wherein positioning the bracket in the second portion comprises coupling the bracket to the positioning member by moving the bracket into the second portion and causing a coupling arm of the bracket to snap into the recess. 
     136. The method of any one of the Clauses herein, wherein:
         the positioning member includes a first side and a second side opposite the first side, the second side including a generally flat base surface,   the bracket includes a base portion and a coupling arm disposed over the base portion, and   positioning the bracket in the second portion comprises positioning the bracket such that the coupling arm is received in a channel of the second portion at the first side.       

     137. The method of any one of the Clauses herein, wherein:
         the positioning member comprises a first side and a second side opposite the first side, the second side including a generally flat base surface,   the bracket includes a base portion and a coupling arm disposed over the base portion, and   positioning the bracket in the second portion comprises positioning the bracket such that the base portion is received at the second side of positioning member.       

     138. An orthodontic appliance, comprising:
         an anchor configured to be positioned adjacent a patient&#39;s teeth; and   an arm extending away from and coupled to the anchor, the arm including a first end portion at the anchor and a second end portion configured to be coupled to a securing member adhered to a tooth of the patient, wherein the second end portion comprises a first region and a second region extending from the first region at an angle, the first region being farther from the anchor than the second region,   wherein the second end portion includes an opening extending through the second end portion.       

     139. The appliance of Clause 138, wherein, when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is secured to the securing member, (a) the second region extends in a generally mesial-distal direction and abuts a coupling arm of the securing member, and (b) the first region abuts a portion of the coupling arm, thereby inhibiting rotation of the second end portion relative to the securing member. 
     140. The appliance any one of the Clauses herein, wherein the opening is an elongate opening such that, when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is secured to the securing member, the opening extends in a generally occlusal-gingival direction. 
     141. The appliance any one of the Clauses herein, wherein the opening is an elongate opening extending through a portion of the first region. 
     142. The appliance any one of the Clauses herein, wherein the opening has a first dimension such that the opening is configured to receive an orthodontic tool. 
     143. The appliance any one of the Clauses herein, wherein the opening has first and second dimensions such that the opening is configured to receive an orthodontic tool. 
     144. The appliance any one of the Clauses herein, wherein the arm further comprises a notch extending from a position of the arm, the notch being at an angle relative to the arm at the position. 
     145. The appliance of any one of the Clauses herein, wherein the notch is generally normal to the arm at the position. 
     146. The appliance of any one of the Clauses herein, wherein the angle is between 60-120 degrees. 
     147. The appliance of any one of the Clauses herein, wherein the notch is a first notch extending in a first direction, the arm further comprising a second notch extending from the position of the arm in a second direction different than first direction. 
     148. The appliance of any one of the Clauses herein, wherein the first direction is generally opposite the second direction. 
     149. The appliance of any one of the Clauses herein, wherein, when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is secured to the securing member, at least one of the first notch or the second notch extends in a generally mesial-distal direction. 
     150. An orthodontic appliance, comprising:
         an anchor configured to be positioned adjacent a patient&#39;s teeth; and   an arm extending away from and coupled to the anchor, the arm including a first end portion at the anchor and a second end portion configured to be coupled to a securing member adhered to a tooth of the patient, wherein the second end portion comprises a first region and a second region extending from the first region at an angle, the first region being farther from the anchor than the second region,   wherein the arm further comprises a notch extending from a position of the arm, the notch being at an angle relative to the arm at the position.       

     151. The appliance of Clause 150, wherein the notch is a first notch extending in a first direction, the arm further comprising a second notch extending from the position of the arm in a second direction different than first direction. 
     152. The appliance of any one of the Clauses herein, wherein the first direction is generally opposite the second direction. 
     153. The appliance of any one of the Clauses herein, wherein, when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is secured to the securing member, at least one of the first notch or the second notch extends in a generally mesial-distal direction. 
     154. An orthodontic appliance, comprising:
         an anchor configured to be positioned adjacent a patient&#39;s teeth; and   an arm extending away from and coupled to the anchor, the arm including a first end portion at the anchor and a second end portion configured to be coupled to a securing member adhered to a patient&#39;s teeth, the second end portion being farther from the anchor than the first end portion, wherein the second end portion comprises first and second extensions extending from a common point, each of the first and second extensions including (i) a first region and (ii) a second region spaced apart from the first region,   wherein the first and second regions of the first extension extend in a first direction and the first and second regions of the second extension extend in a second direction different than the first direction.       

     155. The appliance of Clause 93, wherein, when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is coupled to the securing member, the first extension is biased in a mesial direction and the second extension is biased in a distal direction. 
     156. The appliance of any one of the Clauses herein, wherein, when the second end portion is coupled to the securing member, the first and second regions extend generally in the mesial-distal directions. 
     157. The appliance of any one of the Clauses herein, wherein at least one of the first extension or the second extensions is biased away from the other extension. 
     158. The appliance of any one of the Clauses herein, wherein the second region is farther from the common point than the first region. 
     159. The appliance of any one of the Clauses herein, wherein the first extension is generally a reflection of the second extension about an axis. 
     160. The appliance of any one of the Clauses herein, wherein the second region is at a terminal end portion of the respective extension. 
     161. The appliance of any one of the Clauses herein, wherein the first region is spaced apart from the respective second region such that the first and second regions and a portion of the respective extension define a three-sided opening. 
     162. The appliance of any one of the Clauses herein, wherein the first region is spaced apart from the respective second region such that the first and second regions and a portion of the respective extension define a U-shaped opening. 
     163. The appliance of any one of the Clauses herein, wherein the arm includes a biasing region between the proximal and distal portions, wherein the biasing region is configured to provide a rotational force and/or longitudinal force to at least one of the patient&#39;s teeth when the distal portion is secured to the securing member. 
     164. The appliance of any one of the Clauses herein, wherein at least one of the anchor, the arm, or the securing member comprises nitinol, stainless steel, beta-titanium, cobalt chrome, other metal alloys, polymers, ceramics, and/or combinations thereof. 
     165. The appliance of any one of the Clauses herein wherein, when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is secured to the securing member, the first and second regions of each of the first and second extensions are configured to abuts respective protrusions of the securing member. 
     166. The appliance of any one of the Clauses herein, wherein, when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is secured to the securing member, the first extension is biased in an occlusal direction. 
     167. The appliance of any one of the Clauses here, wherein, when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is secured to the securing member the second extension is biased in a gingival direction. 
     168. The appliance of any one of the Clauses herein, wherein at least one of the first extension or the second extension is biased away from the other extension. 
     169. The appliance of any one of the Clauses herein, wherein the first extension includes a biasing region, wherein, when, the second end portion is coupled to the securing member, the biasing region is configured to bias the first and second regions in the occlusal-gingival direction. 
     170. The appliance of any one of the Clauses herein, wherein the first and second regions of the first extension are farther from the common point than the first and second regions of the second extension. 
     171. The appliance of any one of the Clauses herein, wherein the first and second regions are at a terminal end portion of the respective extension. 
     172. The appliance of any one of the Clauses herein, wherein the first region is spaced apart from the respective second region such that the first and second regions and a portion of the respective extension define a three-sided opening. 
     173. The appliance of any one of the Clauses herein, wherein the first region is spaced apart from the respective second region such that the first and second regions and a portion of the respective extension define a U-shaped opening. 
     174. The appliance of any one of the Clauses herein, wherein the first extension comprises a biasing region such that, when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is secured to the securing member, the biasing region of the first extension is configured to bias the patient&#39;s tooth in the occlusal direction. 
     175. The appliance of any one of the Clauses herein, wherein the arm includes a biasing region between the first and second end portions, wherein the biasing region is configured to provide a rotational force and/or translational force to at least one of the patient&#39;s teeth when the second end portion is secured to the securing member. 
     176. The appliance of any one of the Clauses herein wherein, when the appliance is positioned adjacent the patient&#39;s teeth and the second end portion is secured to the securing member, the first and second regions of each of the first and second extensions are configured to abut respective protrusions of the securing member. 
     177. The appliance of any one of the Clauses herein, wherein at least one of the anchor, the arm, or the securing member comprises nitinol, stainless steel, beta-titanium, cobalt chrome, other metal alloys, polymers, ceramics, and/or combinations thereof. 
     178. An orthodontic appliance, comprising:
         an anchor configured to be positioned adjacent a patient&#39;s teeth; and   an arm extending away from and coupled to the anchor, the arm including a first end portion at the anchor and a second end portion configured to be coupled to a securing member adhered to a tooth of the patient, the second end portion being farther from the anchor than the first end portion, wherein the second end portion comprises a first region, a second region extending from the first region, and a third region extending from the second regions, wherein at least a portion of each of the first and third regions are biased away from one another in opposing directions.       

     179. The appliance of Clause 177, wherein the second end portion is configured to be coupled to a securing member via the first and third regions. 
     180. The appliance of any one of the Clauses herein, wherein at least one of the first region or the third region includes a first protrusion, a second protrusion spaced apart from the first protrusion, and an opening defined by the first and second protrusions, wherein, when the appliance is coupled to the securing member, the first and second protrusions are disposed on opposing sides of a protrusion of the securing member. 
     181. The appliance of any one of the Clauses herein, wherein, when the appliance is coupled to the securing member, the first and second protrusions generally extend in the mesial distal direction. 
     182. The appliance of any one of the Clauses herein, wherein the second region has a curved surface and/or a semi-circular shape. 
     183. The appliance of any one of the Clauses herein, wherein the first, second, and third regions comprise a single component and/or a continuous surface. 
     184. An orthodontic securing member, comprising:
         a base region configured to be coupled to a patient&#39;s tooth; and   first and second protrusions disposed over the base region, each of the first and second protrusions including a first portion extending away from the base region, and a second portion extending from the first portion toward a central area of the base region.       

     185. The securing member of Clause 184, wherein the first and second portions of each of the first and second protrusions define an opening for receiving an end portion of an orthodontic appliance. 
     186. The securing member of any one of the Clauses herein, wherein, when the base region is coupled to the patient&#39;s tooth, the first portions of the first and second protrusions extend in a generally buccal direction away from the patient&#39;s tooth. 
     187. The securing member of any one of the Clauses herein, wherein, when the base region is coupled to the patient&#39;s tooth, the second portions of the first and second protrusions extend in a generally mesial or distal direction. 
     188. The securing member of any one of the Clauses herein, wherein, when the base region is coupled to the patient&#39;s tooth, (i) the second portion of the first protrusion extends in a generally mesial direction, and (ii) the first portion of the first protrusion extends in a generally distal direction. 
     189. The securing member of any one of the Clauses herein, further comprising a third protrusion disposed over an upper portion of the base region, the third protrusion extending from the upper portion and toward the central area of the base region. 
     190. The securing member of any one of the Clauses herein, wherein the third protrusion includes a first portion extending away from the central area, and a second portion extending from the first portion and toward the central area. 
     191. The securing member of any one of the Clauses herein, wherein a terminal end portion of the third protrusion is spaced apart from the base region. 
     192. The securing member of any one of the Clauses herein, wherein the second portion extends in a lateral direction, the appliance further comprising a third protrusion disposed over an upper portion of the base region, the third protrusion extending in the lateral direction across the base region. 
     193. The securing member of any one of the Clauses herein, wherein the third projection defines a surface facing toward the first and second protrusions. 
     194. The securing member of any one of the Clauses herein, further comprising third and fourth protrusions disposed over the base region, each of the third and fourth protrusions including a first portion extending away from the base region, and a second portion extending from the first portion toward a central area of the base region. 
     195. The securing member of any one of the Clauses herein, wherein the third protrusion is spaced apart from the first protrusion to define a first opening and the fourth protrusion is spaced apart from the second protrusion to define a second opening. 
     196. The securing member of any one of the Clauses herein, wherein, when the securing member is coupled to the patient&#39;s tooth, the second portions of the first and second protrusions extend in a generally occlusal-gingival direction. 
     197. The securing member of any one of the Clauses herein, wherein, when the base region is coupled to the patient&#39;s tooth, (i) the second portion of the first protrusion extends in a generally gingival direction, and (ii) the first portion of the first protrusion extends in a generally occlusal direction. 
     198. An orthodontic securing member, comprising:
         a body region configured to be adhered to a patient&#39;s tooth, the body region including a slot; and   a clip portion coupled to the body region, the clip portion being movable relative to the body region from a closed position to an open position, wherein the slot is configured to receive a portion of an orthodontic appliance when the clip portion is in the open position.       

     199. The securing member of Clause 198, wherein the slot is not configured to receive the orthodontic appliance when the clip portion is in the closed position. 
     200. The securing member of any one of the Clauses herein, further comprising a biasing element biasing the clip portion toward the closed position. 
     201. The securing member of any one of the Clauses herein, wherein, when the body region is adhered to a patient&#39;s tooth, movement of the clip portion from the closed position to the open position is generally in the occlusal-gingival direction. 
     202. The securing member of Clause 191, wherein the biasing element is disposed between the body region and clip portion. 
     203. The securing member of any one of the Clauses herein, wherein the body region further comprises a lip portion peripheral to the clip portion, wherein, when the body region is adhered to a patient&#39;s tooth, the lip portion inhibits movement of the clip portion in the lingual or buccal direction. 
     204. An orthodontic system, comprising:
         the appliance of any one of the Clauses herein; and the securing member of any one of the Clauses herein.       

     205. An orthodontic securing member, comprising:
         a cured structure configured to be adhered directly to a patient&#39;s tooth, the cured structure having at least a first portion and a second portion, the first and second portions being spaced apart from one another to define a continuous gap configured to receive an attachment portion of an orthodontic appliance,   wherein the cured structure is configured to secure the attachment portion to the tooth.       

     206. The securing member of Clause 205, wherein the securing member secures the attachment portion to the tooth such that the patient cannot remove the orthodontic appliance. 
     207. The securing member of any one of the Clauses herein, wherein the securing member only includes the cured structure. 
     208. The securing member of any one of the Clauses herein, wherein the securing member does not include a metal. 
     209. The securing member of any one of the Clauses herein, wherein the cured structure comprises a cured composite resin or synthetic material. 
     210. The securing member of any one of the Clauses herein, wherein the cured structure further comprises a third portion, and wherein the first, second, and third portions are spaced apart from one another to define the gap. 
     211. The securing member of any one of the Clauses herein, wherein the cured structure further comprises a third portion and a fourth portion, and wherein the first, second, third, and fourth portions are spaced apart from one another to define the gap. 
     212. The securing member of any one of the Clauses herein, wherein
         the cured structure further comprises a third portion and a fourth portion,   the first, second, third, and fourth portions are spaced apart from one another to define the gap,   the first portion has first abutting portions comprising a gingival-facing surface and a mesial-facing surface,   the second portion has second abutting portions comprising a gingival-facing surface and a distal-facing surface,   the third portion has third abutting portions comprising an occlusal-facing surface and a mesial-facing surface,   the fourth portion has fourth abutting portions comprising an occlusal-facing surface and a distal-facing surface, and   when the appliance is positioned adjacent the patient&#39;s teeth and the attachment portion is engaged with the cured structure, the first, second, third, and fourth abutting portions abut adjacent regions of the attachment portion, thereby opposing rotation and/or translation of the attachment portion relative to the securing member.       

     213. The securing member of any one of the Clauses herein, wherein the gap defines a pattern that is complementary to the portion of the orthodontic appliance to be received by the gap. 
     214. A method for attaching an orthodontic securing member to a patient&#39;s tooth, the method comprising:
         positioning a support containing a curable material adjacent a patient&#39;s tooth such that the curable material on the support engages a patient&#39;s tooth;   after positioning the support, curing the curable material, thereby causing the curable material to obtain a cured structure and/or adhere to the patient&#39;s tooth; and removing the support from the cured structure.       

     215. The method of Clause 213, further comprising engaging an orthodontic appliance with an indentation or opening defined by the cured structure. 
     216. The method of Clause 215, further comprising, after engaging the orthodontic appliance, securing the orthodontic appliance to the cured structure via a moldable material. 
     217. The method of Clause 216, wherein the moldable material comprises a composite resin or synthetic material. 
     218. The method of any one of the Clauses herein, wherein the curable material is a composite resin or synthetic material. 
     219. The method of any one of the Clauses herein, wherein the curable material comprises a photoinitiator. 
     220. An appliance system including an appliance for installing on a patient&#39;s teeth and comprising:
         at least one rigid segment having a length dimension configured to extend along two or more adjacent teeth in a jaw of the patient when the appliance is installed;   at least one bracket connector supported by the at least one rigid segment in and configured to selectively connect to a tooth bracket, the at least one bracket connector including:   a body portion having first and second arm sections that connect to each other at an interface and that each have a free end, the body portion being sufficiently flexible and resilient to allow the free ends of the first and second arm sections to be forced to move toward each other into a compressed state when a sufficient squeezing force is applied to the first and second arm sections, and to resiliently move back away from each other from the squeezed state to an uncompressed or partially uncompressed state when the force is removed;   wherein at least part of the body portion has a first width dimension when the first and second arm sections are in the compressed state and a second width dimension when the first and second arm sections are in the uncompressed state, and wherein the second width dimension is greater than the first width dimension.       

     221. The appliance system of Clause 220, wherein the body portion is configured to be received by the bracket when the first and second arm sections are in the compressed state, and to be locked to the bracket in which it is received, when the first and second arm sections are in the uncompressed state. 
     222. The appliance system of any one of the Clauses herein, wherein the interface at which the first and second arm sections connect to each other is a U-shaped interface. 
     223. The appliance system of any one of the Clauses herein, wherein each of the first and second arm sections has a free end and one or more projections extending from the arm section at or near the free end. 
     224. The appliance system of any one of the Clauses herein, wherein each of the first and second arm sections has a free end and a plurality of projections extending from the arm section at or near the free end. 
     225. The appliance system of Clause 224, further comprising the bracket, including a base configured to be secured to a tooth, a plurality of projections extending from the base, including at least two projections arranged to define a gap between the at least two projections, wherein the gap has a size sufficient to receive the first and second arm sections of the bracket connector between the at least two projections when the first and second arm sections are in the compressed state, and wherein the plurality of projections extending from each arm section are arranged to extend on two respective sides of one of the two projections when the first and second arm sections are received in the gap and in the un-compressed state. 
     226. The appliance system of any one of the Clauses herein, further comprising the bracket, including a base configured to be secured to a tooth, a plurality of projections extending from the base, including at least two projections arranged to define a gap between the at least two projections. 
     227. The appliance system of Clause 226, wherein the gap has a size sufficient to receive the body portion between the at least two projections when the first and second arm sections are in the compressed state, and to be locked to the bracket in which it is received, when the first and second arm sections are in the uncompressed state. 
     228. The appliance system of Clause 226, wherein each of the at least two projections has an extension, extending in a direction away from the gap. 
     229. The appliance system of Clause 226, wherein the at least two projections comprises a plurality of projections on a first side of the gap and a plurality of projections on the second side of the gap. 
     230. The appliance system of Clause 229, wherein the plurality of projections on the first side of the gap include first and second projections that are spaced apart by a distance at least as great as a width dimension of a projection extending from the first or second arm section. 
     231. The appliance system of any one of the Clauses herein, further comprising either (a) at least one arm extending from the at least one first rigid segment, (b) at least one loop or curved feature formed along the length dimension of the second rigid segment, or (c) at least one arm extending from the at least one first rigid segment and at least one loop or curved feature formed along the length dimension of the second rigid segment. 
     232. The appliance system of any one of the Clauses herein, wherein the appliance is configured as single, unitary structure from a single sheet of material. 
     233. A bracket connector for a dental appliance comprising:
         a body portion having first and second arm sections that connect to each other at an   interface and that each have a free end, the body portion being sufficiently flexible and resilient to allow the free ends of the first and second arm sections to be forced to move toward each other into a compressed state when a sufficient squeezing force is applied to the first and second arm sections, and to resiliently move back away from each other from the squeezed state to an uncompressed or partially uncompressed state when the force is removed;   wherein at least part of the body portion has a first width dimension when the first and second arm sections are in the compressed state and a second width dimension when the first and second arm sections are in the uncompressed state, and wherein the second width dimension is greater than the first width dimension.       

     234. The bracket connector of Clause 233, wherein the body portion is configured to be received by a bracket when the first and second arm sections are in the compressed state, and to be locked to the bracket in which it is received, when the first and second arm sections are in the uncompressed state. 
     235. The bracket connector of Clause 233 or 234, wherein the interface at which the first and second arm sections connect to each other is a U-shaped interface. 
     236. The bracket connector of any one of the Clauses herein, wherein each of the first and second arm sections has a free end and one or more projections extending from the arm section at or near the free end. 
     237. The bracket connector of any one of the Clauses herein, wherein each of the first and second arm sections has a free end and a plurality of projections extending from the arm section at or near the free end. 
     238. The bracket connector of any one of the Clauses herein, wherein the bracket connector is configured as single, unitary structure from a single sheet of material. 
     239. A bracket for a dental appliance comprising:
         a base configured to be secured to a tooth;   a plurality of projections extending from the base, including at least two projections   arranged to define a gap between the at least two projections, wherein the gap has a size sufficient to receive the first and second arm sections of the bracket connector between the at least two projections when the first and second arm sections are in the compressed state, and   wherein the plurality of projections extending from each arm section are arranged to extend on two respective sides of one of the two projections when the first and second arm sections are received in the gap and in the un-compressed state.       

     240. An orthodontic appliance, comprising:
         an anchor configured to be positioned adjacent a patient&#39;s teeth; and   a connector extending away from and coupled to the anchor, the connector including an attachment portion and a biasing portion disposed between the anchor and the attachment portion along a longitudinal axis of the connector, wherein the attachment portion is configured to be releasably secured to an orthodontic bracket that is adhered to a tooth of the patient, wherein the attachment portion comprises (a) a base extending along a generally occlusogingival dimension when the appliance is installed in the patient&#39;s mouth, (b) an arm extending away from the base at an angle, wherein the arm is disposed at an intermediate location along length of the base, and wherein the base comprises a proximal region proximal to the intermediate location and a distal region distal to the intermediate location,   wherein, when the appliance is positioned adjacent the patient&#39;s teeth and the attachment portion is secured to the securing member, (a) the arm extends in a generally mesial-distal direction and abuts a coupling arm of the securing member, and (b) each of the proximal and distal regions abut a portion of the coupling arm, thereby inhibiting rotation of the connector relative to the securing member.       

    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Many aspects of the present disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale. Instead, emphasis is placed on illustrating clearly the principles of the present disclosure. 
         FIGS. 1A and 1B  schematically illustrate directional references relative to a patient&#39;s dentition. 
         FIG. 2A  shows the schematic representation of an orthodontic appliance configured in accordance with the present technology installed in a patient&#39;s mouth adjacent the patient&#39;s dentition. 
         FIG. 2B  is a schematic depiction of connection configuration options configured in accordance with embodiments of the present technology. 
         FIG. 2C  is a schematic depiction of a portion of an appliance configured in accordance with embodiments of the present technology. 
         FIGS. 3A and 3B  are elevation views of an appliance configured in accordance with several embodiments of the present technology installed in an upper and lower jaw of a patient&#39;s mouth with the patient&#39;s teeth in an original tooth arrangement and a final tooth arrangement, respectively. 
         FIG. 3C  is a graph showing the stress-strain curves for nitinol and steel. 
         FIGS. 4A-4I  depict an example method of manufacturing an orthodontic appliance in accordance with the present technology. 
         FIG. 5  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 6  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 7  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 8  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 9  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 10  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 11  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 12  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 13  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 14  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 15  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 16  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 17  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 18  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 19  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 20  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 21  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 22  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 23  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 24  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 25  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 26  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 27  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 28  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 29  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 30  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 31  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 32  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 33  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 34  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 35  is an isometric view of a connection configuration in accordance with examples of the present technology. 
         FIG. 36  shows an arm of an orthodontic appliance configured in accordance with examples of the present technology. 
         FIGS. 37-73  show various arm configurations for use with the orthodontic appliances of the present technology. 
         FIG. 74  is an isometric top view of an orthodontic appliance configured in accordance with embodiments of the present technology. 
         FIG. 75  is an isometric top view of an orthodontic appliance configured in accordance with embodiments of the present technology. 
         FIG. 76  is a perspective representation of the orthodontic appliance of  FIG. 75 , installed in a patient&#39;s mouth. 
         FIGS. 77-85  show various configurations of orthodontic appliances configured in accordance with embodiments of the present technology. 
         FIG. 86  shows various arm configurations configured in accordance with embodiments of the present technology. 
         FIGS. 87 and 88  show different arm configurations for use with the orthodontic appliances of the present technology. 
         FIG. 89  shows various arm configurations configured in accordance with embodiments of the present technology. 
         FIG. 90  shows an example appliance configuration in accordance with embodiments of the present technology. 
         FIG. 91  shows various arm configurations configured in accordance with embodiments of the present technology. 
         FIG. 92  shows various arm configurations configured in accordance with embodiments of the present technology. 
         FIG. 93A  is a plan view of a planar version of an orthodontic appliance configured in accordance with embodiments of the present technology. 
         FIG. 93B  is a treatment configuration of the appliance shown in  FIG. 93A . 
         FIG. 94  depicts an orthodontic appliance configured in accordance with embodiments of the present technology, shown installed in a patient&#39;s mouth. 
         FIG. 95  is an enlarged front view of an example arm of an orthodontic appliance in accordance with the present technology. 
         FIGS. 96 and 97  are isometric views of securing members, configured in accordance with embodiments of the present technology. 
         FIGS. 98A, 98B, 98C, and 98D  are isometric, front, top, and side views, respectively, of the attachment portion shown in  FIG. 95  and the securing member shown in  FIG. 96 , configured in accordance with embodiments of the present technology. 
         FIGS. 99-104  are front views of various embodiments of attachment portions and securing members, configured in accordance with embodiments of the present technology. 
         FIG. 105  is an isometric view of an orthodontic device to be disposed over a patient&#39;s teeth, configured in accordance with embodiments of the present technology. 
         FIGS. 106A-106E  are enlarged views of portions of the device shown in  FIG. 105 . 
         FIGS. 107A-107C  illustrate a method for attaching a securing member to a patient&#39;s teeth. 
         FIG. 108  is an isometric view of an example orthodontic device, configured in accordance with embodiments of the present technology. 
         FIG. 109A  is an isometric view of an example orthodontic device, configured in accordance with embodiments of the present technology. 
         FIG. 109B  is an enlarged view of a portion of the device shown in  FIG. 109A . 
         FIGS. 110-113  are isometric views of example arms of an orthodontic appliance, configured in accordance with embodiments of the present technology. 
         FIGS. 114 and 115  are front views of an orthodontic tool to be used with orthodontic appliances of the present technology. 
         FIG. 116  is an enlarged view of the orthodontic tool shown in  FIGS. 114 and 115 . 
         FIGS. 117 and 118  are views of an orthodontic tool in use with orthodontic appliances of the present technology. 
         FIG. 119A  is an isometric view of a securing member, configured in accordance with embodiments of the present technology. 
         FIG. 119B  is an isometric view of an orthodontic appliance, configured in accordance with embodiments of the present technology. 
         FIG. 119C  is an isometric view of the securing member shown in  FIG. 119A  and the attachment portion shown in  FIG. 119B . 
         FIG. 120A  is an isometric view of a securing member, configured in accordance with embodiments of the present technology. 
         FIG. 120B  is an isometric view of the securing member shown in  FIG. 120A  and the orthodontic appliance shown in  FIG. 119B . 
         FIG. 121A  is an isometric view of a securing member, configured in accordance with embodiments of the present technology. 
         FIG. 121B  is an isometric view of an orthodontic appliance, configured in accordance with embodiments of the present technology. 
         FIG. 121C  is an isometric view of the securing member shown in  FIG. 121A  and the orthodontic appliance shown in  FIG. 121B . 
         FIGS. 122 and 123  are isometric views of various embodiments of securing members, configured in accordance with embodiments of the present technology. 
         FIG. 124A  is an isometric view of a securing member, configured in accordance with embodiments of the present technology. 
         FIG. 124B  is an isometric view of an orthodontic appliance, configured in accordance with embodiments of the present technology. 
         FIG. 124C  is an isometric view of the securing member shown in  FIG. 124A  and the orthodontic appliance shown in  FIG. 124B . 
         FIG. 125A  is an isometric view of a securing member, configured in accordance with embodiments of the present technology. 
         FIG. 125B  is an isometric view of an orthodontic appliance, configured in accordance with embodiments of the present technology. 
         FIG. 125C  is an isometric view of the securing member shown in  FIG. 125A  and the orthodontic appliance shown in  FIG. 125B . 
         FIG. 126A  is an isometric view of a securing member formed from a curable material, configured in accordance with embodiments of the present technology. 
         FIG. 126B  is a front view of an orthodontic appliance and the securing member shown in  FIG. 126A , configured in accordance with embodiments of the present technology. 
         FIG. 127A  is an isometric view of a securing member formed from a curable material, configured in accordance with embodiments of the present technology. 
         FIG. 127B  is an isometric view of an orthodontic appliance, configured in accordance with embodiments of the present technology. 
         FIG. 128A  is an isometric view of an orthodontic appliance, configured in accordance with embodiments of the present technology. 
         FIG. 128B  is an isometric view of a pad and the appliance shown in  FIG. 128A , configured in accordance with embodiments of the present technology. 
         FIG. 129  is an isometric view of a securing member, configured in accordance with embodiments of the present technology. 
         FIGS. 130A and 130B  are front and back isometric views, respectively, of a securing member, configured in accordance with embodiments of the present technology. 
         FIG. 130C  is an isometric view of an orthodontic appliance and the securing member shown in  FIGS. 130A and 130B , configured in accordance with embodiments of the present technology. 
         FIG. 131  shows an orthodontic appliance of the present technology positioned in a patient&#39;s mouth. 
         FIGS. 132-134  show several devices configured in accordance with embodiments of the present technology. 
     
    
    
     DETAILED DESCRIPTION 
     I. Definitions 
       FIGS. 1A and 1B  schematically depict several directional terms related to a patient&#39;s dentition. Terms used herein to provide anatomical direction or orientation are intended to encompass different orientations of the appliance as installed in the patient&#39;s mouth, regardless of whether the structure being described is shown installed in a mouth in the drawings. As illustrated in  FIGS. 1A and 1B : “mesial” means in a direction toward the midline of the patient&#39;s face along the patient&#39;s curved dental arch; “distal” means in a direction away from the midline of the patient&#39;s face along the patient&#39;s curved dental arch; “occlusal” means in a direction toward the chewing surfaces of the patient&#39;s teeth; “gingival” means in a direction toward the patient&#39;s gums or gingiva; “facial” means in a direction toward the patient&#39;s lips or cheeks (used interchangeably herein with “buccal” and “labial”); and “lingual” means in a direction toward the patient&#39;s tongue. 
     As used herein, the terms “proximal” and “distal” refer to a position that is closer and farther, respectively, from a given reference point. In many cases, the reference point is a certain connector, such as an anchor, and “proximal” and “distal” refer to a position that is closer and farther, respectively, from the reference connector along a line passing through the centroid of the cross-section of the portion of the appliance branching from the reference connector. 
     As used herein, the terms “generally,” “substantially,” “about,” and similar terms are used as terms of approximation and not as terms of degree, and are intended to account for the inherent variations in measured or calculated values that would be recognized by those of ordinary skill in the art. 
     As used herein, the term “operator” refers to a clinician, practitioner, technician or any person or machine that designs and/or manufactures an orthodontic appliance or portion thereof, and/or facilitates the design and/or manufacture of the appliance or portion thereof, and/or any person or machine associated with installing the appliance in the patient&#39;s mouth and/or any subsequent treatment of the patient associated with the appliance. 
     As used herein, the term “force” refers to the magnitude and/or direction of a force, a torque, or a combination thereof. 
     II. Overview of Orthodontic Appliances of the Present Technology 
       FIG. 2A  is a schematic representation of an orthodontic appliance  100  (or “appliance  100 ”) configured in accordance with embodiments of the present technology, shown positioned in a patient&#39;s mouth adjacent the patient&#39;s teeth.  FIG. 2B  is an enlarged view of a portion of the appliance  100 . The appliance  100  is configured to be installed within a patient&#39;s mouth to impart forces on one or more of the teeth to reposition all or some of the teeth. In some cases, the appliance  100  may additionally or alternatively be configured to maintain a position of one or more teeth. As shown schematically in  FIGS. 2A and 2B , the appliance  100  can comprise a deformable member that includes one or more attachment portions  140  (each represented schematically by a box), each configured to be secured to a tooth surface directly or indirectly via a securing member  160 . The appliance  100  may further comprise one or more connectors  102  (also depicted schematically), each extending directly between attachment portions  140  (“first connectors  104 ”), between an attachment portion  140  and one or more other connectors  102  (“second connectors  106 ”), or between two or more other connectors  102  (“third connectors  108 ”). Only two attachment portions  140  and two connectors  102  are labeled in  FIG. 2A  for ease of illustration. As discussed herein, the number, configuration, and location of the connectors  102  and attachment portions  140  may be selected to provide a desired force on one or more of the teeth when the appliance  100  is installed. Additional details regarding different configurations of connectors  102  are provided elsewhere herein, for example below with reference to  FIGS. 5-35 . 
     The attachment portions  140  may be configured to be detachably coupled to a securing member  160  that is bonded, adhered, or otherwise secured to a surface of one of the teeth to be moved. In some embodiments, one or more of the attachment portions  140  may be directly bonded, adhered, or otherwise secured to a corresponding tooth without a securing member or other connection interface at the tooth. The attachment portions  140  may also be referred to as “bracket connectors” or “male connector elements” herein. The different attachment portions  140  of a given appliance  100  may have the same or different shape, same or different size, and/or same or different configuration. The attachment portions  140  may comprise any one or combination of the attachment portions disclosed herein (including but not limited to attachment portions  9540 ,  9940 ,  10040 ,  10140 ,  10240 ,  10340 ,  10440 ,  11040 ,  11140 ,  11240 ,  11340 ,  11940 ,  12140 ,  12440 ,  12540 ,  12640 ,  12740 ,  12840 ,  12940 ,  13040 ), any one of the bracket connectors and/or male connector elements disclosed herein, as well as any of the attachment portions, bracket connectors, and/or male connector elements disclosed in U.S. patent application Ser. No. 15/370,704 (Publ. No. 2017/0156823) filed Dec. 6, 2016, which is incorporated by reference herein in its entirety. 
     The appliance  100  may include any number of attachment portions  140  suitable for securely attaching the appliance  100  to the patient&#39;s tooth or teeth in order to achieve a desired movement. In some examples, multiple attachment portions  140  may be attached to a single tooth. The appliance  100  may include an attachment portion for every tooth, fewer attachment portions than teeth, or more attachment portions  140  than teeth. In these and other embodiments, the appliance  100  one or more of the attachment portions  140  may be configured to be coupled to one, two, three, four, five or more connectors  102 . 
     As previously mentioned, the connectors  102  may comprise one or more first connectors  104  that extend directly between attachment portions  140 . The one or more first connectors  104  may extend along a generally mesiodistal dimension when the appliance  100  is installed in the patient&#39;s mouth. In these and other embodiments, the appliance  100  may include one or more first connectors  104  that extend along a generally occlusogingival and/or buccolingual dimension when the appliance  100  is installed in the patient&#39;s mouth. In some embodiments, the appliance  100  does not include any first connectors  104 . 
     Additionally or alternatively, the connectors  102  may comprise one or more second connectors  106  that extend between one or more attachment portions  140  and one or more connectors  102 . The one or more second connectors  106  can extend along a generally occlusogingival dimension when the appliance  100  is installed in the patient&#39;s mouth. In these and other embodiments, the appliance  100  may include one or more second connectors  106  that extend along a generally mesiodistal and/or buccolingual dimension when the appliance  100  is installed in the patient&#39;s mouth. In some embodiments, the appliance  100  does not include any second connectors  106 . In such embodiments, the appliance  100  would only include first connectors  104  extending between attachment portions  140 . A second connector  106  and the attachment portion  140  to which it is attached may comprise an “arm,” as used herein (such as arm  130  in  FIGS. 2A and 2B ). In some embodiments, multiple second connectors  106  may extend from the same location along the appliance  100  to the same attachment portion  140 . In such cases, the multiple second connectors  106  and the attachment portion  140  together comprise an “arm,” as used herein. The use of two or more connectors to connect two points on the appliance  100  enables application of a greater force (relative to a single connector connecting the same points) without increasing the strain on the individual connectors. Such a configuration is especially beneficial given the spatial constraints of the fixed displacement treatments herein. Additional details regarding the use of multiple connectors for a discrete connection (such as an arm) are provided elsewhere herein, for example below with reference to  FIGS. 36-57 . 
     Additionally or alternatively, the connectors  102  may comprise one or more third connectors  108  that extend between two or more other connectors  102 . The one or more third connectors  108  may extend along a generally mesiodistal dimension when the appliance  100  is installed in the patient&#39;s mouth. In these and other embodiments, the appliance  100  may include one or more third connectors  108  that extend along a generally occlusogingival and/or buccolingual dimension when the appliance  100  is installed in the patient&#39;s mouth. In some embodiments, the appliance  100  does not include any third connectors  108 . One, some, or all of the third connectors  108  may be positioned gingival to one, some, or all of the first connectors  104 . In some embodiments, the appliance  100  includes a single third connector  108  that extends along at least two adjacent teeth and provides a common attachment for two or more second connectors  106 . In several embodiments, the appliance  100  includes multiple non-contiguous third connectors  108 , each extending along at least two adjacent teeth. 
     As shown in  FIG. 2A , in some embodiments the appliance  100  may be configured such that all or a portion of one, some, or all of the connectors  102  are disposed proximate the patient&#39;s gingiva when the appliance  100  is installed within the patient&#39;s mouth. For example, one or more third connectors  108  may be configured such that all or a portion of the one or more third connectors  108  is positioned below the patient&#39;s gum line and adjacent to but spaced apart from the gingiva. In many cases it may be beneficial to provide a small gap (e.g., 0.5 mm or less) between the third connector(s)  108  and the patient&#39;s gingiva, as contact between the third connector(s)  108  (or any portion of the appliance  100 ) and the gingiva can cause irritation and patient discomfort. In some embodiments, all or a portion of the third connector(s)  108  is configured to be in direct contact with the gingiva when the appliance  100  is disposed in the patient&#39;s mouth. Additionally or alternatively, all or a portion of one or more first connectors  104  and/or second connectors  106  may be configured to be disposed proximate the gingiva. 
     According to some embodiments, one or more connectors  102  may extend between an attachment portion  140  or connector  102  and a joint comprising (a) two or more connectors  102 , (b) two or more attachment portions  140 , or (c) at least one attachment portion  140  and at least one connector  102 . According to some embodiments, one or more connectors  102  may extend between a first joint comprising (a) two or more connectors  102 , (b) two or more attachment portions  140 , or (c) at least one attachment member and at least one connector  102 , and a second joint comprising (a) two or more connectors  102 , (b) two or more attachment portions  140 , or (c) at least one attachment portion  140  and at least one connector  102 . An example of a connector  102  extending between (a) a joint between a second and third connector  106 ,  108 , and (b) a joint between a second connector  106  and an attachment portion  140  is depicted schematically and labeled  109  in  FIG. 2B . 
     Each of the connectors  102  may be designed to have a desired stiffness so that an individual connector  102  or combination of connectors  102  imparts a desired force on one or more of the teeth. In many cases, the force applied by a given connector  102  may be governed by Hooke&#39;s Law, or F=k×x, where F is the restoring force exerted by the connector  102 , k is the stiffness coefficient of the connector  102 , and x is the displacement. In the most basic example, if a connector  102  does not exist between two points on the appliance  100 , then the stiffness coefficient along that path is zero and no forces are applied. In the present case, the individual connectors  102  of the present technology may have varying non-zero stiffness coefficients. For example, one or more of the connectors  102  may be rigid (i.e., the stiffness coefficient is infinite) such that the connector  102  will not flex or bend between its two end points. In some embodiments, one or more of the connectors  102  may be “flexible” (i.e., the stiffness coefficient is non-zero and positive) such that the connector  102  can deform to impart (or absorb) a force on the associated tooth or teeth or other connector  102 . 
     In some embodiments it may be beneficial to include one or more rigid connectors between two or more teeth. A rigid connector  102  is sometimes referred to herein as a “rigid bar” or an “anchor.” Each rigid connector  102  may have sufficient rigidity to hold and maintain its shape and resist bending. The rigidity of the connector  102  can be achieved by selecting a particular shape, width, length, thickness, and/or material. Connectors  102  configured to be relatively rigid may be employed, for example, when the tooth to be connected to the connector  102  or arm is not to be moved (or moved by a limited amount) and can be used for anchorage. Molar teeth, for example, can provide good anchorage as molar teeth have larger roots than most teeth and thus require greater forces to be moved. Moreover, anchoring one or more portions of the appliance  100  to multiple teeth is more secure than anchoring to a single tooth. As another example, a rigid connection may be desired when moving a group of teeth relative to one or more other teeth. Consider, for instance, a case in which the patient has five teeth separated from a single tooth by a gap, and the treatment plan is to close the gap. The best course of treatment is typically to move the one tooth towards the five teeth, and not vice versa. In this case, it may be beneficial to provide one or more rigid connectors between the five teeth. For all of the foregoing reasons and many others, the appliance  100  may include one or more rigid first connectors  104 , one or more rigid second connectors  106 , and/or one or more rigid third connectors  108 . 
     In these and other embodiments, the appliance  100  may include one or more flexible first connectors  104 , one or more flexible second connectors  106 , and/or one or more flexible third connectors  108 . Each flexible connector  102  may have a particular shape, width, thickness, length, material, and/or other parameters to provide a desired degree of flexibility. According to some embodiments of the present technology, the stiffness of a given connector  102  may be tuned via incorporation of a one or more resiliently flexible biasing portions  150 . As shown schematically in  FIG. 2B , one, some, or all of the connectors  102  may include one or more biasing portion  150 , such as springs, each configured to apply a customized force specific to the tooth to which it is attached. 
     As depicted in the schematic shown in  FIG. 2C , the biasing portion(s)  150  may extend along all or a portion of the longitudinal axis L 1  of the respective connector  102  (only the longitudinal axis L 1  for second connector  106  and the longitudinal axis L 2  for third connector  108  is labeled in  FIG. 2C ). The direction and magnitude of the force and torque applied on a tooth by a biasing portion  150  depends, at least in part, on the shape, width, thickness, length, material, shape set conditions, and other parameters of the biasing portion  150 . As such, one or more aspects of the biasing portion  150  (including the aforementioned parameters) may be varied so that the corresponding arm  130 , connector  102 , and/or biasing portion  150  produces a desired tooth movement when the appliance  100  is installed in the patient&#39;s mouth. Each arm  130  and/or biasing portion  150  may be designed to move one or more teeth in one, two, or all three translational directions (i.e., mesiodistal, buccolingual, and occlusogingival) and/or in one, two, or all three rotational directions (i.e., buccolingual root torque, mesiodistal angulation and mesial out-in rotation). 
     The biasing portions  150  of the present technology can have any length, width, shape, and/or size sufficient to move the respective tooth towards a desired position. In some embodiments, one, some, or all of the connectors  102  may have one or more inflection points along a respective biasing portion  150 . The connectors  102  and/or biasing portions  150  may have a serpentine configuration such that the connector  102  and/or biasing portion  150  doubles back on itself at least one or more times before extending towards the attachment portion  140 . For example, in some embodiments the second connectors  106  double back on themselves two times along the biasing portion  150 , thereby forming first and second concave regions facing in generally different directions relative to one another (as an example, see  FIG. 13B ). The open loops or overlapping portions of the connector  102  corresponding to the biasing portion  150  may be disposed on either side of a plane P ( FIG. 2C ) bisecting an overall width W ( FIG. 2C ) of the arm  130  and/or connector  102  such that the extra length of the arm  130  and/or connector  102  is accommodated by the space medial and/or distal to the arm  130  and/or connector  102 . This allows the arm  130  and/or connector  102  to have a longer length (as compared to a linear arm) to accommodate greater tooth movement, despite the limited space in the occlusal-gingival or vertical dimension between any associated third connector  108  and the location at which the arm  130  attaches to the tooth. 
     It will be appreciated that the biasing portion  150  may have other shapes or configurations. For example, in some embodiments the connector  102  and/or biasing portion  150  may include one or more linear regions that zig-zag towards the attachment portion  140 . One, some, or all of the connectors  102  and/or biasing portions  150  may have only linear segments or regions, or may have a combination of curved and linear regions. In some embodiments, one, some, or all of the connectors  102  and/or biasing portions  150  do not include any curved portions. 
     According to some examples, a single connector  102  may have multiple biasing portions  150  in series along the longitudinal axis of the respective connector  102 . In some embodiments, multiple connectors  102  may extend between two points along the same or different paths. In such embodiments, the different connectors  102  may have the same stiffness or different stiffnesses. Additional details regarding the latter embodiments are provided elsewhere herein, for example below with reference to  FIGS. 36-57 . 
     In those embodiments where the appliance  100  has two or more connectors  102  with biasing portions  150 , some, none, or all of the connectors  102  may have the same or different lengths, the same or different widths, the same or different thicknesses, the same or different shapes, and/or may be made of the same or different materials, amongst other properties. In some embodiments, less than all of the connectors  102  have biasing portions  150 . Connectors  102  without biasing portions  150  may, for example, comprise one or more rigid connections between a rigid third connector  108  and the attachment portion  140 . In some embodiments, none of the connectors  102  of the appliance  100  have a biasing portion  150 . 
     According to some embodiments, for example as depicted schematically in  FIG. 2A , the appliance  100  may include a single, continuous, substantially rigid third connector (referred to as “anchor  120 ”) and a plurality of flexible arms  130  extending away from the anchor  120 . When the appliance  100  is installed in the patient&#39;s mouth, each of the arms  130  may connect to a different one of the teeth to be moved and exerts a specific force on its respective tooth, thereby allowing an operator to move each tooth independently. Such a configuration provides a notable improvement over traditional braces in which all of the teeth are connected by a single archwire, such that movement of one tooth can cause unintentional movement of one or more nearby teeth. As discussed in greater detail herein, the independent and customized tooth movement enabled by the appliances of the present technology allows the operator to move the teeth from an original tooth arrangement (“OTA”) to a final tooth arrangement (“FTA”) more efficiently, thereby obviating periodic adjustments, reducing the number of office visits, and reducing or eliminating patient discomfort, and reducing the overall treatment time (i.e., the length of time the appliance is installed in the patient&#39;s mouth) by at least 50% relative to the overall treatment time for traditional braces. 
     The anchor  120  may comprise any structure of any shape and size configured to comfortably fit within the patient&#39;s mouth and provide a common support for one or more of the arms  130 . In many embodiments, the anchor  120  is disposed proximate the patient&#39;s gingiva when the appliance  100  is installed within the patient&#39;s mouth, for example as shown in  FIG. 2B . For instance, the appliance may be designed such that, when installed in the patient&#39;s mouth, all or a portion of the anchor  120  is positioned below the patient&#39;s gum line and adjacent but spaced apart from the gingiva. In many cases it may be beneficial to provide a small gap (e.g., 0.5 mm or less) between the anchor  120  (or any portion of the appliance  100 ) and the patient&#39;s gingiva as contact between the anchor  120  and the gingiva can cause irritation and patient discomfort. In some embodiments, all or a portion of the anchor  120  is configured to be in contact with the gingiva when the appliance  100  is disposed in the patient&#39;s mouth. 
     The anchor  120  may be significantly more rigid than the arms  130  such that the equal and opposite forces experienced by each of the arms  130  when exerting a force on its respective tooth are countered by the rigidity of the anchor  120  and the forces applied by the other arms  130 , and do not meaningfully affect the forces on other teeth. As such, the anchor  120  effectively isolates the forces experienced by each arm  130  from the rest of the arms  130 , thereby enabling independent tooth movement. 
     According to some embodiments, for example as shown schematically in  FIGS. 2A and 2B , the anchor  120  comprises an elongated member having a longitudinal axis L 2  (see  FIG. 2C ) and forming an arched shape configured to extend along a patient&#39;s jaw when the appliance  100  is installed. In these and other embodiments, the anchor  120  may be shaped and sized to span two or more of the patient&#39;s teeth when positioned in the patient&#39;s mouth. In some examples, the anchor  120  includes a rigid, linear bar, or may comprise a structure having both linear and curved segments. In these and other embodiments, the anchor  120  may extend laterally across all or a portion of the patient&#39;s mouth (e.g., across all or a portion of the palate, across all or a portion of the lower jaw, etc.) and/or in a generally anterior-posterior direction. Moreover, the appliance  100  may comprise a single anchor or multiple anchors. For example, the appliance  100  may comprise multiple, discrete, spaced apart anchors, each having two or more arms  130  extending therefrom. In these and other embodiments, the appliance  100  may include one or more other connectors extending between adjacent arms  130 . 
     Any and all of the features discussed above with respect to anchor  120  applies to any of the third connectors  108  disclosed herein. 
     As shown in  FIG. 2B , each of the arms  130  may extend between a proximal or first end portion  130   a  and a distal or second end portion  130   b , and may have a longitudinal axis L extending between the first end portion  130   a  and the second end portion  130   b . The first end portion  130   a  of one, some, or all of the arms  130  may be disposed at the anchor  120 . In some embodiments, one, some, or all of the arms  130  are integral with the anchor  120  such that the first end portion  130   a  of such arms are continuous with the anchor  120 . The arms  130  may extend from the anchor  120  at spaced intervals along the longitudinal axis L 2  of the, as shown in  FIG. 2A . In some embodiments, the arms  130  may be spaced at even intervals relative to each other, or at uneven intervals relative to each other, along the longitudinal axis L 2  of the anchor  120 . 
     One, some, or all of the arms  130  may include an attachment portion  140  at or near the second end portion  130   b . In some embodiments, for example as shown in  FIGS. 2A-2C , one or more of the arms  130  is cantilevered from the anchor  120  such that the second end portion  130   b  of the cantilevered arm(s)  130  has a free distal end portion  130   b . In these and other embodiments, a distal terminus of the attachment portion  140  may coincide with a distal terminus of the arm  130 . The attachment portion  140  may be configured to detachably couple the respective arm  130  to a securing member (e.g., a bracket) that is bonded, adhered, or otherwise secured to a surface of one of the teeth to be moved. In some embodiments, the attachment portion  140  may be directly bonded, adhered, or otherwise secured to a corresponding tooth without a securing member or other connection interface at the tooth. 
     Referring to still to  FIGS. 2A and 2B , one, some, or all of the arms  130  may include one or more resiliently flexible biasing portions  150 , such as springs, each configured to apply a customized force, torque or combination of force and torque specific to the tooth to which it is attached. The biasing portion(s)  150  may extend along all or a portion of the longitudinal axis L 1  of the respective arm  130  between the anchor  120  and the attachment portion  140 . The direction and magnitude of the force and torque applied on a tooth by a biasing portion  150  depends, at least in part, on the shape, width, thickness, length, material, shape set conditions, and other parameters of the biasing portion  150 . As such, one or more aspects of the arm  130  and/or biasing portion  150  (including the aforementioned parameters) may be varied so that the arm  130  and/or biasing portion  150  produce a desired tooth movement when the appliance  100  is installed in the patient&#39;s mouth. Each arm  130  and/or biasing portion  150  may be designed to move one or more teeth in one, two, or all three translational directions (i.e., mesiodistal, buccolingual, and occlusogingival) and/or in one, two, or all three rotational directions (i.e., buccolingual root torque, mesiodistal angulation and mesial out-in rotation). 
     The biasing portions  150  of the present technology can have any length, width, shape, and/or size sufficient to move the respective tooth towards a desired FTA. In some embodiments, one, some, or all of the arms  130  may have one or more inflection points along a respective biasing portion  150 . The arms  130  and/or biasing portions  150  may have a serpentine configuration such that the arm  130  and/or biasing portion  150  doubles back on itself at least one or more times before extending towards the attachment portion  140 . In  FIG. 2B , the arm  130  doubles back on itself two times along the biasing portion  150 , thereby forming first and second concave regions facing in generally different directions relative to one another. The open loops or overlapping portions of the arm  130  corresponding to the biasing portion  150  may be disposed on either side of a plane P bisecting an overall width W of the arm  130  such that the extra length of the arm  130  is accommodated by the space medial and/or distal to the arm  130 . This allows the arm  130  to have a longer length (as compared to a linear arm) to accommodate greater tooth movement, despite the limited space in the occlusal-gingival or vertical dimension between the anchor  20  and the location at which the arm  130  attaches to the tooth. 
     It will be appreciated that the biasing portion  150  may have other shapes or configurations. For example, in some embodiments the arm  130  and/or biasing portion  150  may include one or more linear regions that zig-zag towards the attachment portion  140 . One, some, or all of the arms  130  and/or biasing portions  150  may have only linear segments or regions, or may have a combination of curved and linear regions. In some embodiments, one, some, or all of the arms  130  and/or biasing portions  150  do not include any curved portions. 
     According to some examples, a single arm  130  may have multiple biasing portions  150 . The multiple biasing portions  150  may be in series along the longitudinal axis L 1  of the respective arm  120 . In some embodiments, multiple arms  130  may extend in parallel between two points along the same path or along different paths. In such embodiments, the different arms  130  may have the same stiffness or different stiffnesses. 
     In those embodiments where the appliance  100  has two or more arms  130  with biasing portions  150 , some, none, or all of the arms  130  may have the same or different lengths, the same or different widths, the same or different thicknesses, the same or different shapes, and/or may be made of the same or different materials, amongst other properties. In some embodiments, less than all of the arms  130  have biasing portions  150 . Arms  130  without biasing portions  150  may, for example, comprise one or more rigid connections between the anchor  120  and the attachment portion  140 . In some embodiments, none of the arms  130  of the appliance  100  have a biasing portion  150 . 
     The appliances of the present technology may include any number of arms  130  suitable for repositioning the patient&#39;s teeth while taking into account the patient&#39;s comfort. Unless explicitly limited to a certain number of arms in the specification, the appliances of the present technology may comprise a single arm, two arms, three arms, five arms, ten arms, sixteen arms, etc. In some examples, one, some, or all of the arms  130  of the appliance may be configured to individually connect to more than one tooth (i.e., a single arm  130  may be configured to couple to two teeth at the same time). In these and other embodiments, the appliance  100  may include two or more arms  130  configured to connect to the same tooth at the same time. 
     Any portion of the appliances of the present technology may include a biasing portion  150 . For example, in some embodiments, portion thereof (e.g., the anchor(s), the arm(s), the biasing portion(s), the attachment portion(s), the link(s), etc.) may comprise one or more superelastic materials. 
     Additional details related to the individual directional force(s) applied via the biasing portion  150  or, more generally the arm  130 , are described in U.S. application Ser. No. 15/370,704, now U.S. Pat. No. 10,383,707, issued Aug. 20, 2019, the disclosure of which is incorporated by reference herein in its entirety. 
     The appliances disclosed herein and/or any portion thereof (e.g., the anchor(s), the arm(s), the biasing portion(s), the attachment portion(s), the link(s), etc.) may comprise one or more superelastic materials. The appliances disclosed herein and/or any portion thereof (e.g., the anchor(s), the arm(s), the biasing portion(s), the attachment portion(s), the link(s), etc.) may comprise Nitinol, stainless steel, beta-titanium, cobalt chrome, MP35N, 35N LT, one or more metal alloys, one or more polymers, one or more ceramics, and/or combinations thereof. 
       FIGS. 3A and 3B  are elevation views of the appliance  100  installed on both the upper and lower arches of a patient&#39;s mouth M with the arms  130  coupled to securing members  160  attached to the lingual surfaces of the teeth. It will be appreciated that the appliance  100  of one or both of the upper and lower arches may be positioned proximate a buccal side of a patient&#39;s teeth, and that the securing elements  160  and/or arms  130  may alternatively be coupled to the buccal surface of the teeth. 
       FIG. 3A  shows the teeth in an OTA with the arms  130  in a deformed or loaded state, and  FIG. 3B  shows the teeth in the FTA with the arms  130  in a substantially unloaded state. When the arms  130  are initially secured to the securing members  160  when the teeth are in the OTA, the arms  130  are forced to take a shape or path different than their “as designed” configurations. Because of the inherent memory of the resilient biasing portions  150 , the arms  130  impart a continuous, corrective force on the teeth to move the teeth towards the FTA, which is where the biasing portions  150  are in their as-designed or unloaded configurations. As such, tooth repositioning using the appliances of the present technology can be accomplished in a single step, using a single appliance. In addition to enabling fewer office visits and a shorter treatment time, the appliances of the present technology greatly reduce or eliminate the pain experienced by the patient as the result of the teeth moving as compared to braces. With traditional braces, every time the orthodontist makes an adjustment (such as installing a new archwire, bending the existing archwire, repositioning a bracket, etc.), the affected teeth experience a high force which is very painful for the patient. Over time, the applied force weakens until eventually a new wire is required. The appliances of the present technology, however, apply a movement-generating force on the teeth continuously while the appliance is installed, which allows the teeth to move at a slower rate that is much less painful (if painful at all) for the patient. Even though the appliances disclosed herein apply a lower and less painful force to the teeth, because the forces being applied are continuous and the teeth can move independently (and thus more efficiently), the appliances of the present technology arrive at the FTA faster than traditional braces or aligners, as both alternatives require intermediate adjustments. 
     In many embodiments, the movement-generating force is lower than that applied by traditional braces. In those embodiments in which the appliance comprises a superelastic material (such as nitinol), the superelastic material behaves like a constant force spring for certain ranges of strain, and thus the force applied does not drop appreciably as the tooth moves. For example, as shown in the stress-strain curves of nitinol and steel in  FIG. 3C , the curve for nitinol is relatively flat compared to that of steel. Thus, the superelastic connectors, biasing portions, and/or arms of the present technology apply essentially the same stress for many different levels of strain (e.g., deflection). As a result, the force applied to a given tooth stays constant as the teeth move during treatment, at least up until the teeth are very close or in the final arrangement. The appliances of the present technology are configured to apply a force just below the pain threshold, such that the appliance applies the maximum non-painful force to the tooth (or teeth) at all times during tooth movement. This results in the most efficient (i.e., fastest) tooth movement without pain. 
     In some embodiments, tooth repositioning may involve multiple steps performed progressively, by using multiple appliances. Embodiments involving multiple steps (or multiple appliances, or both) may include one or more intermediate tooth arrangements (ITAs) between an original tooth arrangement (OTA) and a desired final tooth arrangement (FTA). Likewise, the appliances disclosed herein may be designed to be installed after a first or subsequently used appliance had moved the teeth from an OTA to an ITA (or from one ITA to another ITA) and was subsequently removed. Thus, the appliances of the present technology may be designed to move the teeth from an ITA to an FTA (or to another ITA). Additionally or alternatively, the appliances may be designed to move the teeth from an OTA to an ITA, or from an OTA to an FTA without changing appliances at an ITA. 
     In some embodiments, the appliances disclosed herein may be configured such that, once installed on the patient&#39;s teeth, the appliance cannot be removed by the patient. In some embodiments, the appliance may be removable by the patient. 
     Any of the example appliances or appliance portions described herein may be made of any suitable material or materials, such as, but not limited to Nitinol (NiTi), stainless steel, beta-titanium, cobalt chrome or other metal alloy, polymers or ceramics, and may be made as a single, unitarily-formed structure or, alternatively, in multiple separately-formed components connected together in single structure. However, in particular examples, the rigid bars, bracket connectors and loop or curved features of an appliance (or portion of an appliance) described in those examples are made by cutting a two dimensional (2D) form of the appliance from a 2D sheet of material and bending the 2D form into a desired 3D shape of the appliance, according to processes as described in U.S. patent application Ser. No. 15/370,704 (Publ. No. 2017/0156823), filed Dec. 6, 2016, or other suitable processes. 
     Methods of Manufacturing 
       FIGS. 4A-4I  illustrate an example method for designing and fabricating an orthodontic appliance as described herein. The particular processes described herein are exemplary only, and may be modified as appropriate to achieve the desired outcome (e.g., the desired force applied to each tooth by the appliance, the desired material properties of the appliance, etc.). In various embodiments, other suitable methods or techniques can be utilized to fabricate an orthodontic appliance. Moreover, although various aspects of the methods disclosed herein refer to sequences of steps, in various embodiments the steps can be performed in different orders, two or more steps can be combined together, certain steps may be omitted, and additional steps not expressly discussed can be included in the process as desired. 
     As noted above, in some embodiments an orthodontic appliance is configured to be coupled to a patient&#39;s teeth while the teeth are in an OTA. In this position, elements of the appliance exert customized loads on individual teeth to urge them toward a desired FTA. For example, an arm  130  of the appliance  100  can be coupled to a tooth and configured to apply a force so as to urge the tooth in a desired direction toward the FTA. In one example, an arm  130  of the appliance  100  can be configured to apply a tensile force that urges the tooth lingually along the facial-lingual axis. By selecting the appropriate dimensions, shape, shape set, material properties, and other aspects of the arms  130 , a customized load can be applied to each tooth to move each tooth from its OTA toward its FTA. In some embodiments, the arms  130  are each configured such that little or no force is applied once the tooth to which the arm  130  is coupled has achieves its FTA. In other words, the appliance  100  can be configured such that the arms  130  are at rest in the FTA state. 
     The method may begin with obtaining data (e.g., position data) characterizing the patient&#39;s OTA. As depicted in  FIG. 4A , in some embodiments the operator may obtain a digital representation  400  of the patient&#39;s OTA, for example using optical scanning, cone beam computed tomography (CBCT), scanning of patient impressions, or other suitable imaging technique to obtain position data of the patient&#39;s teeth, gingiva, and optionally other adjacent anatomical structures while the patient&#39;s teeth are in the original or pre-treatment condition. 
     The method may further comprise obtaining data (e.g., position data) characterizing the patient&#39;s intended or desired FTA, and in many cases generating a digital representation of the patient&#39;s FTA. The data characterizing the FTA can include coordinates (e.g., X,Y,Z coordinates) for each of the patient&#39;s teeth and the gingiva. Additionally or alternatively, such data can include positioning of each of the patient&#39;s teeth relative to other ones of the patient&#39;s teeth and/or the gingiva. 
     In some embodiments, segmentation software (e.g., iROK Digital Dentistry Studio) be used to create individual virtual teeth and gingiva from the OTA data. Suitable software can be used to move the virtual teeth to their FTA positions. As shown in  FIG. 4B , in some cases digital models of securing members  404  can be added to the OTA digital model  400  (e.g., by an operator selecting positions on the tooth surface for placement of securing members  404  thereon). Suitable software can be used to move the virtual teeth with the attached securing members  404  from the OTA to a desired final position. An example of a digital FTA model with the virtual securing member models  404  attached is shown in  FIG. 4C . 
     As shown in  FIG. 4D , in some embodiments a heat treatment fixture digital model  408  can be obtained. In some embodiments, the heat treatment fixture digital model  408  can correspond to and/or be derived from the FTA digital model (such as the FTA digital model of  FIG. 4C ). For example, the FTA digital model can be modified (e.g., using MeshMixer or other suitable modeling software) in a variety of ways to render a model suitable for manufacturing a heat treatment fixture. In some embodiments, the FTA digital model can be modified to replace the securing members  404  (which are configured to couple to arms  130  of an appliance  100  ( FIG. 2A )) with members  410  (which can be configured to facilitate temporary coupling of the heat treatment fixture to the appliance for shape-setting). Additionally or alternatively, the FTA digital model can be modified to enlarge or thicken the gingiva, to remove one or more of the teeth, and/or to add structural components for increased rigidity. In some embodiments, enlarging or thickening the gingiva may be done to ensure portions (e.g., the anchor) of the fabricated appliance, which is based in part on the FTA digital model, does not engage or contact the patient&#39;s gingiva when the appliance is installed. As a result, modifying the FTA digital model as described herein may be done to provide a less painful teeth repositioning experience for the patient. 
     The method may further comprise obtaining an appliance digital model. As used herein, the term “digital model” and “model” are intended to refer to a virtual representation of an object or collection of objects. For example, the term “appliance digital model” refers to the virtual representation of the structure and geometry of the appliance, including its individual components (e.g., the anchor, arms, biasing portions, attachment portions, etc.). In some embodiments, a substantially planar digital model of the appliance is generated based at least in part on the heat treatment fixture digital model (and/or the FTA digital model). According to some examples, a contoured or 3D appliance digital model generally corresponding to the FTA can first be generated that conforms to the surface and attachment features of the heat treatment fixture digital model. In some embodiments, the 3D appliance digital model can include generic arm portions and securing members, without particular geometries, dimensions, or other properties of the arms being selected or defined by a particular patient. The 3D appliance digital model may then be flattened to generate a substantially planar appliance digital model. In some embodiments, the particular configuration of the arms  130  (e.g., the geometry of biasing portions  150 , the position along the anchor  120  ( FIG. 2A ), etc.) can then be selected so as to apply the desired force to urge the corresponding tooth (to which the arm  130  is attached) from its OTA toward its FTA. As noted previously, in some embodiments the arms are configured so as to be substantially at rest or in a substantially unstressed state when at the FTA. The selected arm configurations can then be substituted or otherwise incorporated into the planar appliance digital model. 
     In some cases, it may be beneficial to evaluate an intended appliance design prior to fabricating a physical appliance based on the intended appliance design to assess how the physical appliance would perform during treatment. For example, because the pre-installation form of the appliance is based at least in part on a desired FTA, the position of one or more portions of the appliance may shift relative to the gingiva once the physical appliance is installed in the patient&#39;s mouth (e.g., with the patient&#39;s teeth in the OTA). As a result, one or more shifted positions of the physical appliance may cause pain for the patient that may reduce treatment compliance and/or satisfaction. 
     In some embodiments, finite element analysis (or other suitable computational techniques) can be used to manipulate the 3D appliance digital model to assess its performance prior to fabrication. For example, as shown in  FIG. 4E , the 3D appliance digital model  414  can be virtually deformed (e.g., using finite element analysis) into a position for engagement with the patient&#39;s teeth in the OTA. As shown in  FIG. 4E , the resulting virtual model  412  represents the appliance digital model  414  after it has been deformed into position to be engaged with the patient&#39;s teeth in the OTA. An output of the virtual deformation can be evaluated to assess whether the physical appliance will function as intended. Based on the evaluation of the output, the intended appliance design can be modified as needed, or a final appliance design can be obtained. In the example shown in  FIG. 4E , a portion of the appliance digital model  414  impinges on the gingiva digital model. As a result, the design of the appliance may be modified, and the evaluation may be repeated until the appliance digital model  414  no longer impinges on the gingiva. This process may be repeated iteratively until a satisfactory appliance design is achieved. 
     Next, the heat treatment fixture can be fabricated. For example, using the heat treatment fixture digital model, the heat treatment fixture can be cast, molded, 3D printed, or otherwise fabricated using suitable materials configured to withstand heating for shape setting of an appliance thereon. 
     In some embodiments, fabricating the appliance includes first fabricating the appliance in a planar configuration based on the planar appliance digital model. For example, as shown in  FIGS. 4F and 4G , a pattern  424  of the planar form of the final device can be cut out of a sheet of material  424  to get a planar member  426 . In some embodiments, the appliance is cut out of a sheet of Nitinol or other metal using laser cutting, water jet, stamping, or other suitable technique. The thickness of the material can be varied across the appliance, for example by electropolishing, etching, depositing, or otherwise manipulating the material of the appliance to achieve the desired material properties. 
     According to some embodiments, the planar member  426  (e.g., as 3D-printed or as cut out from a sheet of material) can be bent or otherwise manipulated into the desired arrangement (e.g., substantially corresponding to the FTA) to form a 3D appliance for treatment. In some embodiments, the planar member  426  can be bent into position by coupling the planar member  426  to a heat treatment fixture  432 , as shown in  FIG. 4H . The heat treatment fixture  432  may be, for example, the physical form of the previously-obtained heat treatment fixture digital model  408 . For example, the arms of the planar member  426  can be removably coupled to hook members of the heat treatment fixture, and optionally ligature wire or other temporary fasteners can be used to secure the arms or other portions of the appliance to the heat treatment fixture  432 . The resulting assembly (i.e., the appliance fastened to the heat treatment fixture) can then be heated to shape-set the appliance into its final form, which can correspond or substantially correspond to the FTA. As a result, the appliance is configured to be in an unstressed state in the FTA. The shape set appliance can then be removed from the heat treatment fixture  432 . 
     In operation, the appliance can then be installed in the patient&#39;s mouth (e.g., by bending or otherwise manipulating arms of the appliance to be coupled to brackets of the patient&#39;s teeth while in the OTA). Due to the shape set of the appliance and the geometry of the arms and anchor, the arms will tend to urge each tooth away from its OTA and toward the FTA. 
     III. Selected Examples of Orthodontic Appliance Configurations 
     The appliances of the present technology may comprise any combination of structural elements to directly or indirectly couple a first tooth (or teeth) to a second tooth (or teeth) and/or another anatomical structure or location within or proximate the oral cavity. The particular configuration may be selected based on one or more desired functional characteristics, such as flexibility, bias force magnitude, bias force direction, durability, and others.  FIGS. 5-34  depict several examples of configurations for use with the appliances of the present technology. Although each configuration is explained with reference to two attachment portions  140 , the appliances of the present technology may ha 
     As shown in  FIG. 5 , the appliance  100  may include one or more connection configurations comprising a first connector  106   a  extending gingivally from a first attachment portion  140   a , a first connector  106   b  extending gingivally from a second attachment portion  140   b , and a third connector  108  extending between the gingival end portions of the first connectors  106   a ,  106   b . The attachment portions  140   a ,  140   b  are not connected by a first connector  104 . In  FIG. 5 , all three of the connectors  106   a ,  106   b , and  108  are generally linear, have a relatively large width w, and do not include any biasing portions. As a result, each of the connectors  106   a ,  106   b , and  108  comprises a rigid connector (i.e., having an infinite stiffness coefficient k) such that the first and second teeth T 1 , T 2  will not move relative to one another. 
     The attachment portions  140   a ,  140   b  utilized in a given connection configuration may have the same or different shape, size, and/or configuration, and may comprise any of the attachment portions, bracket connectors, and/or male connector elements disclosed herein, as well as any of the attachment portions, bracket connectors, and/or male connector elements disclosed in U.S. Pat. No. 10,383,707, filed Dec. 6, 2016, which is incorporated by reference herein in its entirety. Likewise, the appliance carrying the attachment portions  140   a ,  140   b  may be any of the appliances disclosed herein, as well as any of the appliances disclosed in U.S. Pat. No. 10,383,707, filed Dec. 6, 2016. 
     As shown in  FIG. 6 , the appliance  100  may include one or more connection configurations comprising a second connector  106   a  extending gingivally from a first attachment portion  140   a , a second connector  106   b  extending gingivally from a second attachment portion  140   b , and a third connector  108  extending between the gingival end portions of the first and second connectors  106   a ,  106   b . The attachment portions  140   a ,  140   b  are not connected by a first connector  104 . In  FIG. 6 , the second connectors  106   a ,  106   b  are generally linear, have a relatively large width w, and do not include any biasing portions. As a result, each of the second connectors  106   a ,  106   b  comprise a rigid connector (i.e., having an infinite stiffness coefficient k). The first connector  104 , however, has a smaller width and two biasing portions  150  along its longitudinal axis. As a result, the first connector  104  has a positive, non-zero stiffness coefficient. Each of the biasing portions  150  comprise an open loop/U-shaped portion of the first connector  104  that extends in a generally occlusal direction such that each of the biasing portions  150  has a concave portion that faces in a gingival direction. 
     As shown in  FIG. 7 , the appliance  100  may include one or more connection configurations comprising a first connector  104  having a biasing portion  50  such that the first connector  104  has a non-zero, positive stiffness coefficient. As a result, the first connector  104  is relatively flexible and allows for movement between the first and second teeth T 1 , T 2 . The connection configuration of  FIG. 7  does not include any second connectors or third connectors, and thus the attachment portions  140   a ,  140   b  (and associated teeth) are connected only by the first connector  104 . 
     As shown in  FIG. 8 , in some embodiments, the appliance  100  may include one or more connection configurations comprising a first connector  104  that is generally rigid, for example as shown in  FIG. 8 . The first connector  104  does not have a biasing portion and has a relatively larger width. In contrast to the configuration of  FIG. 7 , the first connector  104  of  FIG. 8  does not allow for relative movement between the teeth. Such a configuration may be beneficial, for example, when moving two or more teeth as a group, or when two or more teeth do not require any movement between the OTA and the FTA and so can be used to help anchor the anchor. 
     As shown in  FIG. 9 , the appliance  100  may include one or more connection configurations comprising a second connector  106   a  extending gingivally from a first attachment portion  140   a , a second connector  106   b  extending gingivally from a second attachment portion  140   b , a third connector  108  extending between the gingival end portions of the second connectors  106   a ,  106   b , and a first connector  104  extending between the first and second attachment portions  140   a ,  140   b . In  FIG. 9 , the second connector  106   a , the second connector  106   b , and the third connector  108  are generally linear, have a relatively large width w, and do not include any biasing portions. As a result, each of the connectors  106   a ,  106   b , and  108  comprises a rigid connector (i.e., having an infinite stiffness coefficient k). The first connector  104  includes a single biasing portion  50  and thus has a non-zero, positive stiffness coefficient. However, the overwhelming rigidity provided by the second connector  106   a , second connector  106   b , and third connector  108  dictates that the first and second teeth T 1 , T 2  will not move relative to one another. 
     As shown in  FIG. 10 , the appliance  100  may include one or more connection configurations comprising a second connector  106   a  extending gingivally from a first attachment portion  140   a , a second connector  106   b  extending gingivally from a second attachment portion  140   b , a third connector  108  extending between the gingival end portions of the second connectors  106   a ,  106   b , and a first connector  104  extending between the first and second attachment portions  140   a ,  140   b . In  FIG. 10 , the second connector  106   a  and the second connector  106   b  are generally linear, have a relatively large width w, and do not include any biasing portions. As a result, each of the connectors  106   a ,  106   b  comprises a rigid connector (i.e., having an infinite stiffness coefficient k). The first connector  104  includes a single biasing portion  50  and thus has a non-zero, positive stiffness coefficient, and the third connector  108  includes two biasing portions  150  in series and thus also has a non-zero, positive stiffness coefficient. 
     As shown in  FIG. 11 , the appliance  100  may include one or more connection configurations comprising a second connector  106   a  extending gingivally from a first attachment portion  140   a , a second connector  106   b  extending gingivally from a second attachment portion  140   b , a first connector  104  extending between the first and second attachment portions  140   a ,  140   b , and a third connector  108  extending between the gingival end portions of the second connectors  106   a ,  106   b . In  FIG. 11 , all of the connectors  106   a ,  106   b ,  108 , and  104  are generally linear, have a relatively large width w, and do not include any biasing portions. As a result, each of the connectors  106   a ,  106   b ,  108 ,  104  comprises a rigid connector (i.e., having an infinite stiffness coefficient k) such that the first and second teeth T 1 , T 2  will not move relative to one another. 
     As shown in  FIG. 12 , the appliance  100  may include one or more connection configurations comprising a second connector  106   a  extending gingivally from a first attachment portion  140   a , a second connector  106   b  extending gingivally from a second attachment portion  140   b , a first connector  104  extending between the first and second attachment portions  140   a ,  140   b , and a third connector  108  extending between the gingival end portions of the second connectors  106   a ,  106   b . In  FIG. 12 , the second connector  106   a , the second connector  106   b , and the first connector  104  are generally linear, have a relatively large width w, and do not include any biasing portions. As a result, each of the connectors  106   a ,  106   b ,  104  comprises a rigid connector (i.e., having an infinite stiffness coefficient k). The third connector  108  has a relatively smaller width and two biasing portions  150  in series, and thus has a positive, non-zero stiffness coefficient. However, the overwhelming rigidity provided by the second connector  106   a , second connector  106   b , and first connector  104  dictates that the first and second teeth T 1 , T 2  will not move relative to one another. 
     As shown in  FIG. 13 , the appliance  100  may include one or more connection configurations comprising a second connector  106   a  extending gingivally from a first attachment portion  140   a , a second connector  106   b  extending gingivally from a second attachment portion  140   b , and a third connector  108  extending between the gingival end portions of the second connectors  106   a ,  106   b . The configuration does not include a first connector  104  extending between the attachment portions  140   a ,  140   b . In  FIG. 13 , each of the second connector  106   a  and the second connector  106   b  comprise a single, S-shaped biasing portion  150  along their respective longitudinal axes, while the third connector  108  is generally linear, has a relatively large width w, and does not include any biasing portions. As a result, the third connector  108  comprises a rigid connector (i.e., having an infinite stiffness coefficient k). As a result, the first and second teeth T 1 , T 2  can move relative to one another. 
     As shown in  FIG. 14 , the appliance  100  may include one or more connection configurations comprising a second connector  106   a  extending gingivally from a first attachment portion  140   a , a second connector  106   b  extending gingivally from a second attachment portion  140   b , and a third connector  108  extending between the gingival end portions of the second connectors  106   a ,  106   b . The configuration does not include a first connector  104  extending between the attachment portions  140   a ,  140   b . In  FIG. 14 , each of the second connector  106   a  and the second connector  106   b  comprise a single, S-shaped biasing portion  150  along their respective longitudinal axes, while the third connector  108  comprises two U-shaped biasing portions  150  in series. As a result, the first and second teeth T 1 , T 2  can move relative to one another. 
     As shown in  FIG. 15 , the appliance  100  may include one or more connection configurations comprising a second connector  106   a  extending gingivally from a first attachment portion  140   a , a second connector  106   b  extending gingivally from a second attachment portion  140   b , a first connector  104  extending between the attachment portions  140   a ,  140   b , and a third connector  108  extending between the gingival end portions of the second connectors  106   a ,  106   b . In  FIG. 15 , each of the second connector  106   a  and the second connector  106   b  comprise a single, S-shaped biasing portion  150  along their respective longitudinal axes, and the first connector  104  comprises a single, U-shaped biasing portion  150 . The third connector  108  is generally linear, has a relatively large width w, and does not include any biasing portions. As a result, the third connector  108  comprises a rigid connector (i.e., having an infinite stiffness coefficient k). 
     As shown in  FIG. 16 , the appliance  100  may include one or more connection configurations comprising a second connector  106   a  extending gingivally from a first attachment portion  140   a , a second connector  106   b  extending gingivally from a second attachment portion  140   b , a first connector  104  extending between the attachment portions  140   a ,  140   b , and a third connector  108  extending between the gingival end portions of the second connectors  106   a ,  106   b . In  FIG. 16 , each of the second connector  106   a  and the second connector  106   b  comprise a single, S-shaped biasing portion  150  along their respective longitudinal axes, the first connector  104  comprises a single, U-shaped biasing portion  150 , and the third connector  108  comprises two, U-shaped biasing portions  150  in series. The U-shaped biasing portion  150  of the first connector  104  may be concave in an occlusal direction while both of the U-shaped biasing portions  150  of the third connector  108  may be concave in a gingival direction. 
     As shown in  FIG. 17 , the appliance  100  may include one or more connection configurations comprising a second connector  106   a  extending gingivally from a first attachment portion  140   a , a second connector  106   b  extending gingivally from a second attachment portion  140   b , a first connector  104  extending between the attachment portions  140   a ,  140   b , and a third connector  108  extending between the gingival end portions of the second connectors  106   a ,  106   b . In  FIG. 17 , each of the second connectors  106   a ,  106   b  may comprise a single, S-shaped biasing portion  150  along their respective longitudinal axes, while the first connector  104  and the third connector  108  are generally linear, have a relatively large width w, and do not include any biasing portions. As a result, each of the first and third connectors  104 ,  108  comprise a rigid connector (i.e., having an infinite stiffness coefficient k). 
     As shown in  FIG. 18 , the appliance  100  may include one or more connection configurations comprising a second connector  106   a  extending gingivally from a first attachment portion  140   a , a second connector  106   b  extending gingivally from a second attachment portion  140   b , a first connector  104  extending between the attachment portions  140   a ,  140   b , and a third connector  108  extending between the gingival end portions of the second connectors  106   a ,  106   b . In  FIG. 18 , each of the second connector  106   a  and the second connector  106   b  comprise a single, S-shaped biasing portion  150  along their respective longitudinal axes, and the third connector  108  comprises two, U-shaped biasing portions  150  in series. The U-shaped biasing portions  150  of the third connector  108  may be concave in a gingival direction. The first connector  104  is generally linear, has a relatively large width w, and does not include any biasing portions. As a result, the first connector  104  comprises a rigid connector (i.e., having an infinite stiffness coefficient k). 
     As shown in  FIG. 19 , the appliance  100  may include one or more connection configurations comprising a second connector  106   a  extending gingivally from a first attachment portion  140   a , a second connector  106   b  extending gingivally from a second attachment portion  140   b , a first connector  104  extending between the attachment portions  140   a ,  140   b , and a third connector  108  extending between the gingival end portions of the second connectors  106   a ,  106   b . In  FIG. 19 , the second connector  106   b  comprises a single, S-shaped biasing portion  150  along its respective longitudinal axis, and the first connector  104  comprises a single, U-shaped biasing portion  150 . The second connector  106   a  and the third connector  108  are generally linear, have a relatively large width w, and do not include any biasing portions. As a result, each of the second connector  106   a  and the third connector  108  comprise a rigid connector (i.e., having an infinite stiffness coefficient k). 
     As shown in  FIG. 20 , the appliance  100  may include one or more connection configurations comprising a second connector  106   a  extending gingivally from a first attachment portion  140   a , a second connector  106   b  extending gingivally from a second attachment portion  140   b , a first connector  104  extending between the attachment portions  140   a ,  140   b , and a third connector  108  extending between the gingival end portions of the second connectors  106   a ,  106   b . In  FIG. 20 , the second connector  106   b  comprises a single, S-shaped biasing portion  150  along its respective longitudinal axis, the first connector  104  comprises a single, U-shaped biasing portion  150 , and the third connector  108  comprises two, U-shaped biasing portions  150  in series. The U-shaped biasing portion  150  of the first connector  104  may be concave in an occlusal direction while both of the U-shaped biasing portions  150  of the third connector  108  may be concave in a gingival direction. The second connector  106   a  is generally linear, has a relatively large width w, and does not include any biasing portions. As a result, the second connector  106   a  comprises a rigid connector (i.e., having an infinite stiffness coefficient k). 
     As shown in  FIG. 21 , the appliance  100  may include one or more connection configurations comprising a second connector  106   a  extending gingivally from a first attachment portion  140   a , a second connector  106   b  extending gingivally from a second attachment portion  140   b , and a third connector  108   a  extending between the gingival end portions of the second connectors  106   a ,  106   b . The configuration shown in  FIG. 21  does not include a first connector  104  extending between the attachment portions  140   a ,  140   b , and does not include any rigid connectors. Each of the second connectors  106   a ,  106   b  may comprise a single, S-shaped biasing portion  150  along their respective longitudinal axes, and the third connector  108   a  may comprise two, U-shaped biasing portions  150  in series. Both of the U-shaped biasing portions  150  of the third connector  108   a  may be concave in a gingival direction. In some embodiments, one or both of the biasing portions  150  of third connector  108   a  are concave in an occlusal direction. The connection configuration shown in  FIG. 21  further includes a third connector  108   c  extending gingivally from a gingival end portion of the second connector  106 , a third connector  108   d  extending gingivally from a gingival end portion of the second connector  106   b , and a third connector  108   b  extending between the gingival end portions of third connectors  108   c ,  108   d . The entire length of the third connector  108   b  may be gingival to the entire length of third connector  108   a . The third connector  108   b  may include a single, S-shaped biasing portion  150  with opposing concavities facing in a mesial direction and a distal direction, respectively, such that the third connector  108   b  comprises two generally linear portions spaced apart from one another in the occlusogingival direction. The third connectors  108   a - 108   d  together enclose a cell. 
     As shown in  FIG. 22 , the appliance  100  may include one or more connection configurations comprising a second connector  106   a  extending gingivally from a first attachment portion  140   a , a second connector  106   b  extending gingivally from a second attachment portion  140   b , and a third connector  108   a  extending between the gingival end portions of the second connectors  106   a ,  106   b . The configuration shown in  FIG. 22  does not include a first connector  104  extending between the attachment portions  140   a ,  140   b , and does not include any rigid connectors. Each of the second connectors  106   a ,  106   b  may comprise a single, S-shaped biasing portion  150  along their respective longitudinal axes, and the third connector  108   a  may comprise two, U-shaped biasing portions  150  in series. Both of the U-shaped biasing portions  150  of the third connector  108   a  may be concave in a gingival direction. In some embodiments, one or both of the biasing portions  150  of third connector  108   a  are concave in an occlusal direction. The connection configuration shown in  FIG. 22  further includes a third connector  108   c  extending gingivally from a gingival end portion of the second connector  106 , a third connector  108   d  extending gingivally from a gingival end portion of the second connector  106   b , and a third connector  108   b  extending between the gingival end portions of third connectors  108   c ,  108   d . The entire length of the third connector  108   b  may be gingival to the entire length of third connector  108   a . The third connector  108   b  may include a single, vertically-oriented S-shaped biasing portion  150  with two generally linear portions on either side that are generally aligned with one another along an occlusogingival dimension. The third connectors  108   a - 108   d  together enclose a cell. 
     As shown in  FIG. 23 , the appliance  100  may include one or more connection configurations comprising a second connector  106   a  extending gingivally from a first attachment portion  140   a , a second connector  106   b  extending gingivally from a second attachment portion  140   b , a third connector  108   a  extending between the gingival end portions of the second connectors  106   a ,  106   b , and a rigid first connector  104  extending between the first and second attachment portions  140   a ,  140   b . Each of the second connectors  106   a ,  106   b  comprise a single, S-shaped biasing portion  150  along their respective longitudinal axes, and the third connector  108   a  comprises two, U-shaped biasing portions  150  in series. Both of the U-shaped biasing portions  150  of the third connector  108  may be concave in a gingival direction. In some embodiments, the U-shaped biasing portions  150  may be concave in an occlusal direction. The first connector  104  may be generally linear, has a relatively large width w, and does not include any biasing portions. The connection configuration shown in  FIG. 23  further includes a third connector  108   c  extending gingivally from a gingival end portion of the second connector  106   a , a third connector  108   d  extending gingivally from a gingival end portion of the second connector  106   b , and a third connector  108   b  extending between the gingival end portions of the third connectors  108   c ,  108   d . The entire length of the third connector  108   b  may be gingival to the entire length of third connector  108   a . The third connector  108   b  may include a single, S-shaped biasing portion  150  with opposing concavities facing in a mesial direction and a distal direction, respectively, such that the third connector  108   b  comprises two generally linear portions spaced apart from one another in the occlusogingival direction. The third connectors  108   a - 108   d  together enclose a cell. 
     As shown in  FIG. 24 , the appliance  100  may include one or more connection configurations comprising a flexible second connector  106   a  extending gingivally from a first attachment portion  140   a , a flexible second connector  106   b  extending gingivally from a second attachment portion  140   b , a flexible third connector  108   a  extending between the gingival end portions of the second connectors  106   a ,  106   b , and a rigid first connector  104  extending between the first and second attachment portions  140   a ,  140   b . Each of the second connectors  106   a ,  106   b  may comprise a single, S-shaped biasing portion  150  along their respective longitudinal axes, and the third connector  108   a  may comprise two, U-shaped biasing portions  150  in series. Both of the U-shaped biasing portions  150  of the third connector  108   a  may be concave in a gingival direction. In some embodiments, one or both of the U-shaped biasing portions  150  of the third connector  108   a  may be concave in an occlusal direction. The first connector  104  is generally linear, has a relatively large width w, and does not include any biasing portions. The connection configuration shown in  FIG. 24  further includes a third connector  108   c  extending gingivally from a gingival end portion of the second connector  106   a , a third connector  108   d  extending gingivally from a gingival end portion of the second connector  106   b , and a third connector  108   b  extending between the gingival end portions of the third connectors  108   c ,  108   d . The third connector  108   b  may include a single, vertically-oriented S-shaped biasing portion  150  with two generally linear portions on either side that are generally aligned with one another along an occlusogingival dimension. The entire length of the third connector  108   b  may be gingival to the entire length of third connector  108   a . The third connectors  108   a - 108   d  together enclose a cell. 
     As shown in  FIG. 25 , the appliance  100  may include one or more connection configurations comprising a second connector  106   a  extending gingivally from a first attachment portion  140   a , a second connector  106   b  extending gingivally from a second attachment portion  140   b , and a third connector  108   a  extending between the gingival end portions of the second connectors  106   a ,  106   b . The configuration shown in  FIG. 25  does not include a first connector  104  extending between the attachment portions  140   a ,  140   b , and does not include any rigid connectors. Each of the second connectors  106   a ,  106   b  may comprise relatively short segments. The third connector  108   a  may comprise a single U-shaped biasing portion  150  that is concave in a gingival direction. In some embodiments, the biasing portions  150  of third connector  108   a  is concave in an occlusal direction. The connection configuration shown in  FIG. 25  further includes a third connector  108   c  extending gingivally from a gingival end portion of the second connector  106   a , a third connector  108   d  extending gingivally from a gingival end portion of the second connector  106   b , and a third connector  108   b  extending between the gingival end portions of third connectors  108   c ,  108   d . In contrast to the configuration shown in  FIG. 24 , for example, only a portion of the length of the third connector  108   b  may be gingival to the entire length of third connector  108   a . The third connector  108   b  may include a single, vertically-oriented S-shaped biasing portion  150  with two generally linear portions on either side that are generally aligned with one another along an occlusogingival dimension. The third connectors  108   a - 108   d  together enclose a cell. 
       FIGS. 25-33  depict several additional example configurations, labeled in accordance with the present technology. 
     As shown in  FIG. 34 , in some embodiments the appliance  100  may include a portion in which a single, flexible third connector  3402  extends from the anchor  120  (or another more rigid third connector  108 ) and splits into two flexible second connectors  3406 ,  3400 , each of which terminates at a corresponding attachment portion  140   a ,  140   b . The third connector  3402  and each of the second connectors  3406 ,  3400  may include a biasing portion (as shown). In some embodiments, the third connector  3402  and/or one or both second connectors  3406 ,  3000  do not include a biasing portion and/or are rigid. 
     It will be appreciated that the first connectors  104 , second connectors  106 , third connectors  108 , and other connectors of the present technology may include zero, three, four, five, six, or more biasing portions. Likewise, even though a particular connector may be shown or described with a particular type of biasing portion, it will be appreciated that the connectors can have any type of shape or biasing portion. 
     In some embodiments one or more of the arms of the appliance  100  may comprise multiple second connectors  106  extending from another more rigid connector to the same attachment portion  140 . The use of two or more connectors to connect two points on the appliance  100  (such as the anchor and an attachment portion) enables application of a greater force (relative to a single connector connecting the same points) without increasing the strain on the individual connectors. Such a configuration is especially beneficial given the spatial constraints of the fixed displacement treatments herein. Additional details regarding the use of multiple connectors for a discrete connection (such as an arm) are provided below. 
       FIG. 36  is an isolated view of a portion of an appliance having an arm  130  comprising two second connectors  150   a ,  150   b  extending between the anchor  120  and the attachment portion (not shown). Each of the connectors  150   a ,  150   b  may have a first end  130   a  at the anchor  120  and a second end  130   b  at the attachment portion. The connectors  150   a ,  150   b  may be separated by a gap  172  between their first and second ends  130   a ,  130   b . In the embodiment shown in  FIG. 36 , each of the connectors  150   a ,  150   b  also comprise a biasing portion. While the arm  130  is shown with two serpentine connectors  150   a ,  150   b  running parallel to one another, in some embodiments the arm may include more than two connectors. In these and other embodiments, the individual connectors may extend along the same or different paths and/or have the same or different shapes. 
     As shown in  FIG. 37 , in some embodiments the arm  130  includes one or more bridges  170  extending across the gap  172  and coupling the second connectors  150   a ,  150   b  at various locations along the lengths of the connectors  150   a ,  150   b . The inclusion of one or more bridges  170  can increase the overall stiffness of the arm. Arm  130   a , for example, has more bridges  170  and is stiffer than arm  130   b , and arm  130   b  has more bridges and is stiffer than arm  130   c . For those embodiments having more than one bridge, the multiple bridges  170  may have the same or different lengths. As demonstrated in  FIG. 38 , the width of one or both of the connectors  150   a ,  150   b  may be increased to increase a stiffness of the individual connector, or may be decreased to decrease the stiffness of the individual connector. The different connectors  150   a ,  150   b  may have the same or different widths. 
     As shown in  FIGS. 39-42 , the bridges  170  may be spaced at even intervals along the length of the arm, or may be positioned at random or uneven intervals. In some embodiments the arm  130  may include a first bridge closer to the anchor and a second bridge closer to the attachment portion  140 . 
       FIG. 43  shows additional examples of multiple connector-arm configurations. It will be appreciated that any of the attachment portions herein may be coupled to an anchor (or another connector) via multiple connectors. 
     As demonstrated in  FIG. 44 , the width of one or both of the connectors  150   a ,  150   b  may be increased to increase a stiffness of the individual connector, or may be decreased to decrease the stiffness of the individual connector. The different connectors  150   a ,  150   b  may have the same or different widths. 
       FIG. 45  shows an example arm  130  comprising multiple connectors  150   a - 150   c . As shown in  FIG. 45 , fewer than all of the connectors extend the entire length between the anchor  120  and the attachment portion  140 . For example, connectors  150   a ,  150   b , and another connector (not labeled) all start at the anchor  120 , but only connector  150   b  travels the entire length of the arm to the attachment portion  140 . As shown in  FIG. 46 , in some embodiments the arm may comprise three or more connectors, all of which extend the entire length of the arm between the anchor and the attachment portion. 
     According to some embodiments, for example as shown in  FIGS. 47 and 48 , the multiple connectors may create a path between the anchor  120  and the attachment portion  140  that includes one or more substantially linear segments. The substantially linear segments may extend in an occlusogingival direction or a mesiodistal direction. 
     As shown in  FIGS. 49-57 , the multiple connectors can form multiple turns between the anchor  120  and the attachment portion  140 . The turns may be stacked in a mesiodistal direction, or may be stacked in an occlusogingival direction. The peaks (more occlusal) of sequential turns may be aligned along an occlusogingival axis, or may be offset. In these and other embodiments, the valleys (more gingival) of sequential turns may be aligned along an occlusogingival axis, or may be offset. 
       FIG. 58  depicts two arms  130   a ,  130   b  of the present technology, each having flexible connector  150  with a plurality of openings  5800  along its length. A thickness of the sidewalls  5802  of the openings  5800  may be increased or decreased to affect the flexibility of the arm. 
     As shown in  FIGS. 59-74 , a single, flexible connector may form multiple turns between the anchor  120  and the attachment portion  140 . For example, the arm may form two or more stacks of turns  5900   a ,  5900   b , where the turns are stacked in the occlusogingival direction. The stacks may be separated by a generally linear portion of the arm. In some embodiments, the arm may form two or more stacks of turns where the turns are stacked in the mesiodistal direction. In some embodiments, the arm may include both mesiodistal and occlusogingival stacks. The peaks (more occlusal or more mesial) of sequential turns may be aligned along an occlusogingival axis, or may be offset. In these and other embodiments, the valleys (more gingival or more mesial) of sequential turns may be aligned along an occlusogingival axis, or may be offset. 
     The example appliance  7400  shown in  FIG. 74  includes an anchor  7412  and a plurality of arms  7414  extending from the anchor  7412 . The anchor  7412  is formed in an arch shape (an arch shaped member having a generally arch-shaped configuration). The anchor  7412  is configured to extend along two or more (or a plurality of) adjacent teeth in one of the patient&#39;s jaws, when the appliance  7400  is installed, as described herein. 
     The anchor  7412  has a lengthwise dimension that includes a first portion  7412   a  that is configured to extend along the incisor, lateral incisor, and cuspid (canine) teeth. The lengthwise dimension of the anchor  7412  includes further second and third portions  7412   b  and  7412   c  configured to extend along some or all of the bicuspid and molar teeth. In other embodiments, the anchor  7412  may be smaller in length and, for example, may include the first portion  7412   a  (or a portion of the first portion  7412   a ), but no second or third portions  7412   b ,  7412   c . In other embodiments, the anchor  7412  may include the first portion  7412   a  and a portion of the length of one or each of the second and third portions  7412   b ,  7412   c . In some embodiments, the appliance may include one or more second and third portions  7412   b ,  7412   c  (of any suitable length) and no first portion  7412   a . In yet other embodiments, the appliance may include one or more anchor second and third portions  7412   b ,  7412   c  (of any suitable length) and Z embodiment appliance features or other appliance features in the location of first portion  7412   a  (instead of an anchor portion) connecting second and third portions  7412   b ,  7412   c.    
     The plurality of arms  7414  may extend from the anchor  7412  at spaced intervals along the longitudinal axis L 2  of the anchor  7412 . The plurality of arms  7414  may be spaced at even intervals relative to each other, or at uneven intervals relative to each other, along the length dimension of the anchor  7412 . In particular examples, the arms  7414  are provided at locations along the length dimension of the anchor  7412  that correspond to or are associated with locations of teeth (or, in further particular examples, to the FTA of each tooth) to which the arms connect, when the appliance is installed. 
     Each arm  7414  includes a spring portion (or spring member)  7414   a  and a bracket connector element (or male connector element)  7414   b . Each spring member  7414   a  in the appliance  7400  may correspond to any of the spring members or spring portions on arms described in U.S. patent application Ser. No. 15/370,704 (Publ. No. 2017/0156823) or herein. Each bracket connector element (or male connector element)  7414   b  in the appliance  7400  may correspond to any of the bracket connectors (or male connector elements) described in U.S. patent application Ser. No. 15/370,704 (Publ. No. 2017/0156823) or herein. 
     In the example in  FIG. 74 , the appliance  7400  includes ten arms  7414  extending from the anchor  7412 , including five arms on the right side and five arms on the left side of the appliance. A respective one of the arms  7414  is located at each respective distal end of the anchor  7412 . The five arms on the right side of the appliance  7400  are spaced apart and located along the length section  7412   b , and the five arms on the left side of the appliance  74100  are spaced apart and along the length section  7412   c  of the anchor  7412 . In other examples, the appliance  7400  may include fewer or more arms along one or both length sections  7412   b  and  7412   c . In those or other examples, some or all of the arms  7414  may extend from the section  7412   a  of the anchor  7412 . 
     In the example shown in  FIG. 74 , the arm  7414  closest to the section  7412   a  on the right side of the appliance and the arm  7414  closest to the section  7412   a  on the left side of the appliance are, each connected to (by being either coupled to or integral with) a respective end of a further rigid section of additional rigid material (or second rigid bar)  7416 . The further rigid section  7416  extends along and adjacent to section  7412   a  of the anchor  7412 . In other examples, the further rigid section  7416  may also or alternatively extend along and adjacent some or all of the length of section  7412   b  or of section  7412   c  (or of both sections  7412   b  and  7412   c ) of the anchor  7412 . While the appliance  7400  in  FIG. 74  includes one further rigid section  7416 , other examples may include two or more further rigid sections of additional rigid material  7416  (for example, arranged over and adjacent two or more of the sections  7412   a ,  7412   b , and  7412   c , or of portions of those sections). 
     The further rigid section  7416  has a plurality of bracket connectors  7417  along its length dimension. The further rigid section  7416  also has a plurality of loop or curved features  7418  formed along its length dimension. 
     Each bracket connector  7417  may be a bracket connector (or male connector element) corresponding to any of the bracket connectors (or male connector elements) described in U.S. patent application Ser. No. 15/370,704 (Publ. No. 2017/0156823) or herein. Alternatively, some or all of the bracket connectors  7417  may have other suitable bracket connector configurations. In the example of  FIG. 74 , the bracket connectors  7417  have a configuration corresponding to the bracket connectors  266 ,  267 ,  268  or  269  described with respect to FIG. 29 in U.S. patent application Ser. No. 16/865,323. 
     In the example in  FIG. 74 , four bracket connectors  7417  extend from the further rigid section  7416 . The bracket connectors  7417  are spaced apart and located along the length dimension of the further rigid section  7416  and, thus, along at least a portion of the corresponding length dimension of section  7412   a  of the anchor  7412 . In other examples, the appliance  100  may include fewer or more bracket connectors  7417 . In particular examples, the bracket connectors  7417  are provided at locations along the length dimension of the further rigid section  7416  that correspond to or are associated with locations of teeth to which the bracket connectors  7417  connect, when the appliance is installed. 
     One or more (or each) of the loop or curved features  7418  in the further rigid section  7416  may be configured to provide a flexibility or a bias or spring force in one or more directions (or both), a force magnitude, durability, or other characteristic, based in part on the shape, material and configuration of the feature  7418 . In certain examples, as shown in  FIG. 74 , the appliance  7400  includes five loop or curved features  7418  along the length of the further rigid section  7416 . Also, in certain examples, as shown in  FIG. 74 , one bracket connector  7417  is located between each adjacent pair of the loop or curved features  7418 . 
     The loop or curved features  7418  may include a loop or curved feature  7418   a  located on the left end of the further rigid section  7416 , and a loop or curved feature  7418   b  located on the right end of the further rigid section  7416 . In such examples, the further rigid section  7416  may connect to arms  7414  extending from the anchor  7412 , through the loop or curved feature  7418   a  and  7418   b . Accordingly, one or both of the loop or curved feature  7418   a  or  7418   b  can be configured to provide one or more of a desired flexibility, bias force magnitude, bias force direction, durability or other characteristics at the interfaces of arms extending from the anchor  7412  and the further rigid section  7416 . 
     In the example in  FIG. 74 , all of the bracket connectors  7417  on the further rigid section  7416  are located between the loop or curved features  7418   a  and  7418   b . In other examples, one or more of the bracket connectors  7417  may be located between one or both features  7418   a  or  7418   b  and the respective arms  7414  that are connected to the ends of the further rigid section  7416 . 
     Other examples may include more or less than five loop or curved features along the length of the further rigid section  7416 , more or less than one bracket connector  7417  between each adjacent pair of loop or curved features  7418 , or more than one loop or curved feature  7418  between two adjacent bracket connectors  7417 . The number, configuration and location of the bracket connectors  7417  and the loop or curved features  7418  may be selected for the appliance  7400 , to provide (when the appliance is installed) the desired teeth connection positions and desired forces on the teeth, as described herein. For example, the number, configuration and location of the bracket connectors  7417  and the loop or curved features  7418  may be selected to move one or more teeth from an original tooth arrangement (OTA) to the final tooth arrangement (FTA), or to an intermediate tooth arrangement (ITA), or from an ITA to an FTA or another ITA. 
     The appliance  7400  is configured to be installed on a patient, by coupling the bracket connector elements  7414   b  and bracket connectors  7417  to corresponding brackets (or female connector elements) that have been secured to the patient&#39;s teeth (or to a selected number of teeth) in one of the patient&#39;s jaws. The brackets or female connector elements may have any suitable configuration and may be secured to a patient&#39;s teeth in any suitable manner including, but not limited to the configurations and manners of securing described in connection with the brackets or female connector elements at reference numbers 700, 1300, 1501, 1601, 1706, 2600, and 2610 in U.S. patent application Ser. No. 15/370,704 (Publ. No. 2017/0156823). 
     The appliance  7400  and associated brackets (or female connector elements), may be manufactured in any suitable manners, including, but not limited to any of the manners of manufacturing any of the appliances or brackets (or female connector elements) as described in U.S. patent application Ser. No. 15/370,704 (Publ. No. 2017/0156823), including, but not limited to molding, casting, machining, 3D printing, stamping, extruding, or the like. However, in particular examples, the appliance  7400  or female connector elements (or both) are made by cutting a two dimensional (2D) form of the appliance from a 2D sheet of material and bending the 2D form into a desired 3D shape of the appliance, according to processes as described in U.S. patent application Ser. No. 15/370,704 (Publ. No. 2017/0156823) or other suitable processes. In those or other examples, the appliance  100  may be configured in a single, unitary structure, from a single sheet (or type) of material. In other examples, the appliance  7400  may be configured from multiple components that are coupled together in any suitable manner such as, but not limited to, welds, solder, adhesives, press or friction fitting, mechanical connector, or the like. 
     In the examples described with reference to  FIG. 74 , the appliance  7400  includes a combination of X and Z features (including one or more features of one or more examples according to embodiment Z and one or more features of one or more examples according to embodiment X). With regard to features according to embodiment X, the appliance  7400  includes one or more (or a plurality) of separate arms  7414  that extend from the one or more rigid bars  7412 . With regard to features examples according to embodiment Z, the appliance  7400  also includes one or more rigid bars  7416  having one or more bracket connectors  7417  and one or more loop or curved feature  7418  (force applying feature) formed along its length dimension. 
     Another example of an appliance  7500  having a combination of X and Z features is shown in  FIGS. 75 and 76 . The appliance  7500  is shown in  FIG. 75  in an uninstalled state (not installed on a patient). The appliance  7500  is shown in  FIG. 76  in an installed state (installed on the teeth of a patient). The appliance  7500  includes an anchor  7522  that corresponds to the anchor  7412  of appliance  7400 . However, the anchor  7522  has a lengthwise dimension including a section  7522   a  that is configured to extend along the incisor, lateral incisor, and cuspid (canine) teeth, and further sections  7522   b  and  7522   c  configured to extend along some, but not all of the bicuspid or molar teeth, when the appliance is installed. In other embodiments, the anchor  7522  may be smaller in length and, for example, may include section  7522   a  (or a portion of section  7522   a ), but no portions of sections  7522   b  or  7522   c . In other embodiments, the anchor  7522  may include section  7522   a  and a longer section  7522   b  or a longer section  7522   c  that extend to molar teeth on one side of the appliance  7522 , when the appliance is installed. The anchor  7522  may be formed in an arch shape (an arch shaped member having a generally arch-shaped configuration) that is configured to extend along two or more (or a plurality of) adjacent teeth in one of the patient&#39;s jaws, when the appliance  7500  is installed. 
     A plurality of arms  7530  extend from the anchor  7522 . The arms  7530  of the appliance  7500  may correspond in structure and function as described with regard to the arms  7414  of the appliance  7400 . For example, the arms  7530  may include spring members and bracket connectors (or male connector elements) similar to those described with regard to arms  7414  of the appliance  7400 . The arms  7530  may be spaced along the length dimension of the anchor  7522  in a manner similar to the spacing described with regard to arms  7414  on the anchor  7412 . However, in the appliance  7500 , at least some of the arms  7530  are located along the anchor section  7522   a  that is configured to extend along some or all of the incisor, lateral incisor, and cuspid (canine) teeth. In other examples, the appliance  7500  may include a further rigid section extending along the anchor section  7522   a , or along some or all of the anchor sections  7522   b  or  7522   c  (such as, but not limited to the further rigid section  7416  of the appliance  7400 ), instead of or in addition to one or more (or all) of the arms  7530  located along the anchor section  7522   a  (or along sections  7522   b  or  7522   c ). 
     In the example in  FIG. 75 , the appliance  7500  includes ten arms  7530  extending from the anchor  7522 , including six arms extending from the anchor section  7522   a , two arms extending from the anchor section  7522   b  and two arms extending from the anchor section  7522   c . In other examples, the appliance  7500  may include fewer or more arms along one or more of the length sections  7522   a ,  7522   b  and  7522   c.    
     The appliance  7500  also includes further rigid sections (or second rigid bars)  7526  and  7527 , extending from the right side end and the left side end, respectively of the anchor  7522 . Each further rigid section  7526  and  7527  has a lengthwise dimension extending from one end of the anchor  7522  to a distal end  7526   a  and  7527   a , respectively. In other examples, the appliance  7500  may include one of the further rigid sections  7526  or  7527 , but not the other further rigid section  7527  or  7526 . In those or other examples, the appliance  7500  may include one or more further rigid sections (similar to the further rigid sections  7526  and  7527 ) located along a portion (or all) of the length of the anchor section  7522   a , instead of (in place of) the anchor section  7522   a.    
     In the example in  FIG. 75 , the further rigid section  7526  has a shape that corresponds to (or is a mirror image of) the shape of the further rigid section  7527 . In other examples, the further rigid section  7526  may have a shape and configuration that is different from the shape and configuration of the further rigid section  7527 . 
     Each further rigid section  7526  and  7527  has a plurality of bracket connectors  7528  and a plurality of loop or curved features  7529  formed along its length dimension. The distal end of each further rigid section  7526  and  7527  may include a portion of a bracket connector  7528   a . Each of the bracket connectors  7528 , and loop or curved features  7529  may correspond in structure, arrangement and function to any of the various examples described with regard to the bracket connectors  7417  and loop or curved features  7418  of the appliance  7400 . In other examples, one or more (or all) of the bracket connectors  7528 , or features  7529  may have other suitable structures, configurations or functions. 
     In certain examples, such as shown in  FIG. 75 , the loop or curved features  7529  may include a loop or curved feature  7529   a  at or adjacent the location at which the further rigid section  7526  extends from the anchor  7522 , and a further loop or curved feature  7529   b  at or adjacent the location at which the further rigid section  7527  extends from the anchor  7522 . In such examples, the further rigid sections  7526  and  7527  may connect to the anchor  7522 , through the loop or curved feature  7529   a  or  7529   b . In some examples, the loop or curved features  7529   a  and  7529   b  may be a curved or loop feature on an arm extending from the anchor  7522  (for example, similar to an arm  30 ). Accordingly, one or both of the loop or curved feature  7529   a  or  7529   b  can be configured to provide one or more of a desired flexibility, bias force magnitude, bias force direction, durability or other characteristics at the interfaces of the anchor  7522  and the further rigid sections  7526  and  7527 . 
     In the example in  FIG. 75 , all of the bracket connectors  7528  on the left side of the appliance  7500  are located between the loop or curved feature  7529   a  and the distal end  7526   a  of the further rigid section  7526 . Similarly, all of the bracket connectors  7528  on the right side of the appliance  7500  are located between the loop or curved feature  7529   b  and the distal end  7527   a  of the further rigid section  7527 . In other examples, one or more of the bracket connectors  7528  may be located between the loop or curved feature  7529   a  or  7529   b  and the anchor distal ends  7526   a  or  7527   a , respectively. 
     Similar to the appliance  7400 , the number, configuration and location of the arms  7530 , bracket connectors  7528  and loop or curved features  7529  may be selected for the appliance  7500 , to provide (when the appliance is installed) the desired teeth connection positions and desired forces on the teeth, as described herein. For example, the number, configuration and location of the arms, the bracket connectors, and the loop or curved features may be selected to move one or more teeth from an original tooth arrangement (OTA) to the final tooth arrangement (FTA), or to an intermediate tooth arrangement (ITA), or from an ITA to an FTA or another ITA. 
     With regard to features according to embodiment X, the appliance  7500  includes one or more (or a plurality) of separate arms  30  that extend from the one or more rigid bars  7522 . With regard to features examples according to embodiment Z, the appliance  7500  also includes one or more rigid bars  7526  or  7527  having one or more bracket connectors  7528  and one or more loop or curved feature  7529  (force applying feature) formed along its length dimension. 
     Another example of an appliance having a combination of X and Z features is described with regard to the 2D member  7700  for forming an appliance, as shown in  FIG. 77 . The 2D appliance member  7700  in  FIG. 77  is configured to be bent or otherwise formed into a 3D appliance in any suitable manner, including processes as described in U.S. patent application Ser. No. 15/370,704 (Publ. No. 2017/0156823). However, an appliance having features as described with regard to the example in  FIG. 77  may be made according to other suitable processes. 
     An appliance in accordance with the example of  FIG. 77  may be made and used in manners similar or corresponding to such manners described herein for appliances  7400  and  7500 . An appliance according to the example of  FIG. 77  may include certain features corresponding in structure or function (or both) to some of the features of appliance  7400  or appliance  7500 . 
     For example, the appliance member  7700  includes an anchor  7742  that corresponds to the anchor  7412  of appliance  7400 . The anchor  7742  has a lengthwise dimension including a section  7742   a  that is configured to extend along the incisor, lateral incisor, and cuspid (canine) teeth, and further sections  7742   b  and  7742   c  configured to extend along some, but not all of the bicuspid or molar teeth, when the appliance formed from the appliance member  7700  is installed. In other embodiments, the anchor  7742  may be smaller in length and, for example, may include section  7742   a  (or a portion of section  7742   a ), but no portions of sections  7742   b  or  7742   c . In other embodiments, the anchor  7742  may include section  7742   a  and a longer section  7742   b  or a longer section  7742   c  that extend to molar teeth on one side of the appliance, when the appliance is formed and installed. In yet other embodiments, the appliance may include an anchor  7742  having a length dimension, with one or two second rigid bars (or further rigid bar sections) having Z embodiment features (for example, corresponding to the second rigid bars  7526  or  7527  of the appliance  7500 ). 
     The anchor  7742  may have an arch shape (an arch shaped member having a generally arch-shaped configuration) that is configured to extend along two or more (or a plurality of) adjacent teeth in one of the patient&#39;s jaws, when the appliance is formed and installed. A plurality of arms  7744  extend from the anchor  7742 . The arms  7744  may correspond in structure and function as described with regard to the arms  7414  or  7530  of the appliance  7400  or  7500 . For example, the arms  7744  may include spring members and bracket connectors (or male connector elements) similar to those described with regard to arms  7414  and  7530 . 
     The arms  7744  may be spaced along the length dimension of the anchor  7742  in a manner similar to the spacing described with regard to arms  7414  on the anchor  7412 . However, in the appliance member  7700 , at least some of the arms  7744  are located along the anchor section  7742   a  that is configured to extend along some or all of the incisor, lateral incisor, and cuspid (canine) teeth. In other examples, the appliance member  7700  may include a further rigid section extending along the anchor section  7742   a , or along some or all of the anchor sections  7742   b  or  7742   c  (such as, but not limited to the further rigid section  7416  of the appliance  7400 ), instead of one or more (or all) of the arms  7744  located along the anchor section  7742   a  (or along sections  7742   b  or  7742   c ). 
     In the example in  FIG. 77 , the appliance member  7700  includes sixteen arms  7744  extending from the anchor  7742  to fourteen bracket connectors  7745   a - 7745   n . One or more (or all) of the bracket connectors may be connected to or part of two respective arms  7744 , such as shown in  FIG. 77  with regard to the bracket connectors  7745   a  and  7745   b . One or more (or all) of the other bracket connectors may be connected to or part of a single arm  7744 , such as shown in  FIG. 77  with regard to the bracket connectors  7745   c - 7745   n . In other examples, the appliance member  7700  may include fewer or more arms along one or more of the length sections  7742   a ,  7742   b  and  7742   c . Also, the appliance member  7700  of other examples may include fewer or more bracket connectors. 
     An appliance member according to the example in  FIG. 77  includes one or more second rigid bars extending to and between two or more of the bracket connectors. In the example in  FIG. 77 , the appliance member  7700  includes a second rigid bar having segments  7746   a ,  7746   b  and  7746   c  extending between bracket connectors  7745   b ,  7745   c ,  7745   d  and  7745   e . The appliance  7740  includes another second rigid bar having segments  7746   d ,  7746   e ,  7746   f  and  7746   g  extending between the bracket connectors  7745   j ,  7745   k ,  7745   l ,  7745   m  and  7745   n . In other examples, the number and configuration of second rigid bars and segments  7746   a - g , and the number and location of bracket connectors  7745   a - 7745   n  to and between which the second rigid bar segments extend, is selected to provide a desired flexibility or force, or both, as described herein. 
     Each second rigid bar segment  7746   a - 7746   g  may have one or more (or a plurality of) loop or curved features  7748  formed along its length dimension. Each of the bracket connectors  7745   a - 7745   n  and loop or curved features  7748  may correspond in structure, arrangement and function to any of the various examples described with regard to the bracket connectors  7417  and loop or curved features  7418  of the appliance  7400 . In other examples, one or more (or all) of the bracket connectors  7745   a - 7745   n , or features  7748  may have other suitable structures, configurations or functions. One or more of the loop or curved features  7748  can be configured to provide one or more of a desired flexibility, bias force strength, bias force direction, between two or more of the bracket connectors  7745   a - 7745   n.    
     In certain examples, such as shown in  FIG. 77 , the appliance member (or appliance) may include an anchor holder, for anchoring the appliance to a patient&#39;s palate. In the example in  FIG. 77 , the appliance member  7700  includes an anchor holder  7749  or Nance. The anchor holder  7749  is connected to (by being either coupled to or integral with) the anchor  7742 . In the example in  FIG. 77 , the anchor holder  7749  has a rounded, plate-shaped head portion  7749   a  connected to the anchor  7742 , through a narrowed neck section  7749   b . A plurality of apertures is provided in the head portion  7749   a  and the neck portion  7749   b  of the anchor holder  7749 . When the appliance is formed and installed, one or more temporary anchorage devices TADs (or other suitable anchorage devices) may be extended through the one or more apertures in the anchor holder  7749 , and into the patient&#39;s palate (soft and hard tissue), to anchor the appliance to the patient&#39;s palate. In particular examples, the anchor holder  7749  is for soft tissue anchorage, where soft tissue is used to help anchor the appliance. In some examples, the appliance member (or appliance), including the anchor holder, may lay against the soft tissue in the patient&#39;s palate, without the use of TADs (or other suitable anchoring devices), when the appliance is installed. In other examples, TADs or other suitable anchor holders may be employed. An anchor holder (such as, but not limited to the anchor holder  7749 ) may be included in any of the example embodiments described herein. 
     Another example of an appliance having a combination of X and Z features is described with regard to the 2D member  7800  for forming an appliance, as shown in  FIG. 78 . The 2D appliance member  7800  in  FIG. 78  is configured to be bent or otherwise formed into a 3D appliance in any suitable manner, including processes as described in U.S. patent application Ser. No. 15/370,704 (Publ. No. 2017/0156823). However, an appliance having features as described with regard to the example in  FIG. 78  may be made according to other suitable processes. 
     An appliance in accordance with the example of  FIG. 78  may be made and used in manners similar or corresponding to such manners described herein for the appliances  7400  or  7500  or the appliance member  7700 . An appliance according to the example of  FIG. 78  may include certain features corresponding in structure or function (or both) to some of the features of the appliance  7400  or the appliance  7500 , or the appliance member  7700 . 
     For example, the appliance member  7800  includes an anchor  7852  that corresponds to the anchor  7412  of the appliance  7400 , or the anchor  7522  of the appliance  7500 , or the anchor  7742  of the appliance member  7700 . The anchor  7852  has a lengthwise dimension that is configured to extend along the incisor, lateral incisor, and cuspid (canine) teeth, when the appliance is formed and installed. Further rigid bars or bar sections  7853  and  7854  are connected to (coupled to or extended from) the anchor  7852 , to extend along some or all of the bicuspid or molar teeth, when the appliance formed from the appliance member  7850  and is installed. In other examples, the anchor  7852  may be smaller in length than shown in  FIG. 78  and, for example, may extend along some (but not all) of the incisor, lateral incisor, and cuspid (canine) teeth when the appliance is formed and installed. In other examples, the anchor  7852  may extend further along bicuspid or molar teeth (in place of some or all of one or both bar or bar sections  7853  and  7854 ) when the appliance is formed and installed. In yet other examples, one or both sections  7853  and  7854  may be omitted or smaller than shown in  FIG. 78 . 
     The anchor  7852  may have an arch shape (an arch shaped member having a generally arch-shaped configuration) that is configured to extend along two or more (or a plurality of) adjacent teeth in one of the patient&#39;s jaws, when the appliance is formed and installed. A plurality of arms  7856  extend from the anchor  7852 . The arms  7856  may correspond in structure and function as described with regard to the arms  7414 ,  7530  or  7744  of the appliance  7400  or  7500  or the appliance member  7700 . For example, the arms  7856  may include spring members and bracket connectors (or male connector elements) similar to those described with regard to arms  7414 ,  7530  or  7744 . 
     The arms  7856  may be spaced along the length dimension of the anchor  7852  in a manner similar to the spacing described with regard to arms  7414  on the anchor  7412  in  FIG. 74 , or the arms  7744  on the anchor  7742  in  FIG. 77 . In the appliance member  7800 , all of the arms  7856  are located along the anchor  7852  that is configured to extend along some or all of the incisor, lateral incisor, and cuspid (canine) teeth. 
     In the example in  FIG. 78 , the appliance member  7800  includes six arms  7856  extending from the anchor  7852  to six corresponding bracket connectors  7857 . Each respective bracket connector  7857  may be connected to or part of a single respective arm  7856 , such as shown in  FIG. 78 . In other examples, one or more (or all) of the bracket connectors may be connected to or part of two respective arms (for example, similar to the manner shown in  FIG. 77  with regard to the bracket connectors  7745   a  and  7745   b ). In other examples, the appliance member  7800  may include fewer or more arms along the length of rigid bar  7852 . Also, the appliance member  7800  of other examples may include fewer or more bracket connectors. 
     An appliance member according to the example in  FIG. 78  includes one or more further rigid bars or bar sections  7853  and  7854  connected to the anchor  7852 . Each further rigid bar  7853  and  7854  may have one or more (or a plurality of) loop or curved features and one or more (or a plurality of) bracket connectors (or male connector elements) along its length dimension. In the example in  FIG. 78 , the anchors  7853  and  7854  have a total of eight loop or curved features  7858   a - 7858   h  and eight bracket connectors (or male connector elements)  7859   a - 7859   h . In other examples, each rigid bar  7853  and  7854  may have more or less loop or curved features or bracket connectors than shown in the example of  FIG. 78 . 
     Each of the bracket connectors  7859  and loop or curved features  7858  may correspond in structure, arrangement and function to any of the various examples described with regard to the bracket connectors  7417  and loop or curved features  7418  of the appliance  7400 , or with regard to the bracket connectors  7745   a - 7745   n  and loop or curved features  7748  of the appliance member  7700 . In other examples, one or more (or all) of the bracket connectors  7859 , or features  7858  may have other suitable structures, configurations or functions. One or more of the loop or curved features  58  can be configured to provide one or more of a desired flexibility, bias force strength, bias force direction, between two or more of the bracket connectors  7859 . 
     In certain examples, such as shown in  FIG. 78 , the loop or curved features  7858  may include a loop or curved feature  7858   a  at or adjacent the location at which the further rigid bar  7853  extends from the anchor  7852 , and a further loop or curved feature  7858   e  at or adjacent the location at which the further rigid bar  7854  extends from the anchor  7852 . In such examples, the further rigid bars  7853  and  7854  may connect to the anchor  7852 , through the loop or curved feature  7858   a  or  7858   e . Accordingly, one or both of the loop or curved feature  7858   a  or  7858   e  can be configured to provide one or more of a desired flexibility, bias force magnitude, bias force direction, durability or other characteristics at the interfaces of the anchor  7852  and the further rigid bars  7853  and  7854 . 
     Other example appliances (or appliance members)  7900 ,  8000 ,  8100  and  8200  having a combination of X and Z features are shown in  FIGS. 79-82 , respectively, and may be made and used in manners similar or corresponding to such manners described herein for the appliances  7400  or  7500 , or the appliance members  7700  or  7800 . An appliance according to any of the examples of  FIGS. 79-82  may include certain features corresponding in structure or function (or both) to some of the features of the appliances  7400  or  7500 , or the appliance members  7700  or  7800 . 
     In particular, each of the appliances (or appliance members)  7900 ,  8000 ,  8100  and  8200  includes one or more rigid bars and one or more (or a plurality) of separate arms that extend from the one or more rigid bars, for example, in accordance with X embodiment features described herein. In particular, the appliance (or appliance member)  7900  includes two rigid bars  7962  and  7963 . The appliance  8000  (or appliance member) includes an anchor  8072 . The appliance  8100  includes an anchor  8182 , and the appliance  8200  (or appliance member) includes an anchor  8292 . Each of the anchors  7962 ,  8182  and  8292  have a lengthwise dimension that is configured to extend along two or more teeth, when the appliance is formed and installed. However, each of the anchors  7963  and  8072  has a lengthwise dimension that is configured to extend along one tooth, when the appliance is formed and installed. The anchors  7962 ,  7963 ,  8072 ,  8183  and  8292  may each correspond in structure to the anchor  7412  of the appliance  7400 , the anchor  7522  of the appliance  7500 , the anchor  7742  of the appliance member  7700  or the anchor  7852  of the appliance member  7800 . Other examples may include any suitable number, size and locations of rigid bars. 
     Each of the appliances (or appliance members)  7900 ,  8000 ,  8100  and  8200  includes one or more (or a plurality of) arms extending from the one or more rigid bars. For example, the appliance (or appliance member)  7900  includes two arms  7964   a  and  7964   b  extending from the anchor  7962 , and a third arm  7964   c  extending from the anchor  7963 . The appliance (or appliance member)  8000  includes one arm  8074  extending from the anchor  8072 . The appliance (or appliance member)  8100  includes arms  8184   a  and  8184   b  extending from the anchor  8182 . The appliance  8200  (or appliance member) includes one arm  8294  extending from the anchor  8292 . Each of the arms extends to a respective bracket connector (or male connector element). 
     Each of the appliances (or appliance members)  7900 ,  8000 ,  8100  and  8200  includes one or more further rigid sections having Z embodiment features, and connected to (by being coupled to or integral with) the anchor  7962 ,  7963 ,  8072 ,  8183  or  8292 , through one or more arms. For example, the appliance (or appliance member)  7900  includes a further rigid section  7966  connected to the anchor  7962  through arms  7964   a  and  7964   b , and connected to the anchor  7963  through the arm  7964   c . Similarly, the appliance (or appliance member)  8000  includes a further rigid section  8076  that is connected to the anchor  8072  through the arm  8074 . Also similarly, the appliance (or appliance member)  8100  includes a further rigid section  8186  that is connected to the anchor  8182  through an arm  8184   b . Also similarly, the appliance (or appliance member)  8200  includes a further rigid section  8296  that is connected to the anchor  8292  through an arm  8294 . 
     Each of the further rigid sections  7966 ,  8076 ,  8186  and  8296  have a length dimension extending in a generally arch shaped configuration. One or more bracket connectors and one or more loop or curved feature (force applying feature) are provided along the length dimension of the one or more further rigid sections  7966 ,  8076 ,  8186  and  8296 . For example, the rigid section  7966  of the appliance (or appliance member)  7900  has eight bracket connectors  7968  and seven loop or curved features  7969 . Similarly, the rigid section  8076  of the appliance (or appliance member)  8000  has eight bracket connectors  8078  and seven loop or curved features  8079 , the rigid section  8186  of the appliance (or appliance member)  8180  has eight bracket connectors  8188  and seven loop or curved features  8189 , and the rigid section  8296  of the appliance (or appliance member)  8290  has eight bracket connectors  8298  and seven loop or curved features  8299 . Any of the examples described herein may include one or more further bracket connectors that are connected to an anchor, but not to the further rigid section, such as the bracket connector at the distal end of the arm  8184   a  in the appliance (or appliance member)  8100  of  FIG. 81 . 
     In the examples shown in  FIGS. 79-82 , each loop or curved feature ( 7969 ,  8079 ,  8189 , or  8299 ) is located between a pair of adjacent bracket connectors ( 7968 ,  8078 ,  8188  or  8298 ) along the length dimension of the further rigid section ( 7966 ,  8076 ,  8186  or  8296 , respectively). In other examples, the further rigid section may include no loop or curved feature (or two or more loop or curved features) between any of the adjacent pairs of bracket connectors. The number, configuration and location of loop or curved features on the further rigid bar  7966 ,  8076 ,  8186  or  8296  may be selected to provide the desired teeth connection positions and desired forces on the teeth, when the appliance is installed, as described herein. 
     Additional examples of appliances (or appliance members) are shown in  FIGS. 83-85 , each including a plurality of further rigid sections, each having Z embodiment features. In the example appliance (or appliance member)  8300  in  FIG. 83  has four further rigid sections  8352 ,  8353 ,  8354  and  8355  extending from a T-shaped central rigid bar  8356 . The central rigid bar  8356  has a generally T shape. The example appliance (or appliance member)  8400  of  FIG. 84 , has four further rigid sections  8462 ,  8463 ,  8464  and  8465  extending from a central rigid palate plate  8466 . The central rigid palate plate  8466  has a shape to fit against a patient&#39;s palate. The example appliance (or appliance member)  8500  in  FIG. 85  has four further rigid sections  8572 ,  8573 ,  8574  and  8575  extending from a central annular-shaped rigid bar  8576 . In any of the appliances described herein, one or more of the arms or loop or curved features or bracket connector elements may be omitted, and replaced with a portion of the anchor or further rigid section that is formed to be rigid with minimal or no flexibility, for example for improved anchorage. 
     In each of the examples in  FIGS. 74-85 , the appliance (or an appliance member) includes one or more X embodiment features (in combination with one or more Z embodiment features), including one or more (or a plurality of) arms, extending to one or more (or a plurality of) bracket connectors (or male connector elements). One or more (or each) of the arms may include one or more spring member features. Any of the arms, spring members, and bracket connectors (or male connector elements) of  FIGS. 74-85  may have any suitable configuration, including the configurations shown in the respective drawings of those  FIGS. 74-85 . In other examples, any one or more of the arms, spring members, or bracket connectors (or male connector elements) in any of those or other appliances (or appliance members) described herein may have other suitable configurations according to any of the other arms, spring members, or bracket connectors (or male connector elements) described herein. 
     Further examples of arms that may be employed as one or more of the arms in any of the examples described herein or in U.S. patent application Ser. No. 15/370,704 (Publ. No. 2017/0156823), or yet other appliance examples, are described with reference to  FIGS. 86-90 . Each of the example arms extends from an anchor to an associated bracket connector (or male connector element). The anchor may correspond to the anchor in any of the examples of  FIGS. 74-85 , or the anchor of any other examples described herein, or of yet other appliance or appliance member examples. 
     Each of the arms  8600 - 8608 ,  8909 - 8930 ,  9031  and  9032  includes a spring member  8600   b - 8608   b ,  8909   b - 8930   b ,  9031   b  and  9032   b . In other examples, an arm may include more than one spring member. In particular examples, each spring member has a configuration (including a shape, material, and size) that provides one or more of a desired flexibility, bias force magnitude, bias force direction, durability or other characteristics The number, configuration and location of the spring members may be selected to provide (when the appliance is installed) the desired forces on the teeth to which the bracket connectors of the appliance connect, when the appliance is installed as described herein. For example, the number, configuration and location of the spring members may be selected to move one or more teeth from an original tooth arrangement (OTA) to the final tooth arrangement (FTA), or to an intermediate tooth arrangement (ITA), or from an ITA to an FTA or another ITA. 
     The arm  8600  includes a spring member  8600   b  that has a shape having two open loop portions arranged adjacent each other in a horizontal direction (direction generally parallel to the length dimension of the anchor  8633 ), forming an “S” shape laying in that horizontal direction. In other examples, the spring member may have one open loop or more than two open loops. In the example of  FIG. 86 , the bracket connector  8600   a  of the arm  8600  is located vertically above the location at which the arm couples to or extends from the anchor  8633  (and is centered along an axis A perpendicular to the length dimension of the anchor  8633  at the location at which the arm  8600  connects to the anchor  8633 ). In other examples, the bracket connector  8600   a  may be located laterally offset from the axis A (e.g., toward the right or the left of the axis A). 
     The arm  8600  in the example in  FIG. 86  includes a linear arm section  8600   c  that extends from the spring member  8600   b  to the bracket connector  8600   a . In some examples, the linear arm section  8600   c  may extend along the axis A as shown in  FIG. 86 . In other examples, the linear arm section  8600   c  may be laterally spaced from but parallel to the axis A, or may extend at an angle transverse (non-parallel) to the axis A. In other examples, the arm section  8600   c  may be nonlinear (curved or other suitable shape) or may be omitted (such that the spring member  8600   b  extends to the bracket connector  8600   a ). In certain examples, the arm section  8600   c  (or corresponding arm section of other arms described herein) has a sufficient length dimension to be gripped by an operator, doctor or other trained personnel (e.g., with a tool, such as, but not limited to a Weingart tool as described herein) during installation of an appliance, to help guide the bracket connector  8600   a  into engagement with a bracket. 
     The two open loop portions of the spring member  8600   b  of the arm  8600  have a generally rectangular shape, including one or more straight edges (e.g., the horizontal and vertical edges of the spring member  8600   b  in  FIG. 86 ) that meet at rounded corners. In other examples, the open loop portions of the spring member may have curved edges or may be elongated in the vertical (axis A) direction or in the horizontal direction (perpendicular to axis A), or in a direction that is at an obtuse angle relative to the axis A. 
     For example, the arm  8601  in  FIG. 86  has a spring member  8601   b  and arm section  8601   c  that is similar in shape and configuration to the spring member  8600   b  and arm section  8600   c  of the arm  8600 . However, the two open loop portions of the spring member  8601   b  of the arm  8601  have rounded edges. In addition, the two open loop portions of the spring member  8601   b  are more elongated in the vertical direction (direction of axis A) than in a horizontal direction (perpendicular to the direction of axis A). In other examples, the open loop portions of the spring member  8601   b  may be more elongated in the horizontal direction than in in the vertical direction, or in a direction at an obtuse angle relative to the axis A. Similarly, other examples of the spring member  8600   b  of the arm  8600  may have loop portions that are more elongated in the vertical direction, the horizontal direction, or an obtuse angled direction, relative to the axis A. 
       FIG. 86  shows another example of an arm  8602  that includes a spring member  8602   b  with a shape having two open loop portions arranged adjacent each other in a horizontal direction (direction generally parallel to the length dimension of the anchor  8633 ), forming an “S” shape laying in that horizontal direction. However, the center of the bracket connector  8602   a  of the arm  8602  is laterally offset from the axis A, such that the bracket connector  8602   a  is located mostly or entirely on one side of the axis A (the left side in  FIG. 86 ). In other examples, the spring member  8602   b  may be oriented in the opposite direction as shown, such that the bracket connector  8602   a  is located mostly or entirely on the other side of the axis A (the right side in  FIG. 86 ). 
     In the arm  8602 , the spring member  8602   b  is configured such that the entire spring member  8602   b  (or substantially the entire spring member  8602   b ) is located vertically below the bracket connector  8602   a  (between the bracket connector  8602   a  and the anchor  8633 ). In other examples, some or all of the spring member  8602   b  may be located laterally offset from the bracket connector  8602   a  (in a direction perpendicular to the axis A). 
     For example, the arm  8603  in  FIG. 86  has a spring member  8603   b  and arm section  8603   c  that is similar in shape and configuration to the spring member  8602   b  and arm section  8602   c  of the arm  8602 . However, the two open loop portions of the spring member  8603   b  are spread out in the lateral direction more than the open loop portions of the spring member  8602   b . As a result, a substantial portion of the spring member  8603   b  (e.g., one of the loop portions) is laterally offset from the bracket connector  8603   a  in a direction perpendicular to the axis A. 
     The arm  8604  has a has a spring member  8604   b  and arm section  8604   c  that is similar in shape and configuration to the spring member  8603   b  and arm section  8603   c  of the arm  8603 . However, the two loop portions of the spring member  8604   b  are shaped different from the loop portions  8603   b . In particular, one of the open loop features of the spring member  8604   b  has a “U” shape, with one of the sides or arms of the “U” shape loop extending to the bracket connector  8604   a  and the other side or arm of the “U” shape loop extending from the other loop of the spring member  8604   b . In addition, the length of the arm section  8604   c  is smaller than the length of the arm section  8603   c . In certain examples, the length of the arm section  8600   c - 8630   c  may be selected, to provide a desired distance between the bracket connector  8600   a - 8630   a  and the anchor  8633 . The arm section length may be selected to accommodate or fit a desired or particular patient tooth arrangement. 
       FIG. 86  shows other examples arms  8605 ,  8605 ′,  8606 ,  8607  and  8608  that include a spring member with a shape having two or more open loop portions arranged adjacent each other in a horizontal direction (direction generally parallel to the length dimension of the anchor  8633 ), forming an “S” shape laying in that horizontal direction. 
     The arms  8605  and  8605 ′ in  FIG. 86  are each connected to the same (a common) bracket connector, such that the bracket connector  8605   a  is connected to the anchor  8633  through the two arms  8605  and  8605 ′. The arm  8605  has a spring member  8605   b  that is similar in shape to the spring member  8603   b , but oriented in the opposite direction. The arm  8605 ′ has a spring member  8605   b ′ that is similar in shape to the spring member  8602   b . In other examples, the arms  8605  and  8605 ′ may have a spring member having any suitable configuration, shape and size such as, but not limited to the other examples of spring members described herein or in U.S. patent application Ser. No. 15/370,704 (Publ. No. 2017/0156823). 
     The arm  8606  in  FIG. 86  includes a spring member  8606   b  having more than two (i.e., four) open loop portions. Other examples of that spring member or other spring members described herein may include any suitable number of loop portions. The spring member  8607   b  of the arm  8607  of  FIG. 86  has loop portions that are elongated in a direction that is at an obtuse angle relative to the axis A. The arm  8608  in  FIG. 86  has a spring member  8608   b  that is similar in shape to the spring member  8603   b . However, the arm  8608  has an arm section  8608   c  that is wider (in the horizontal dimension) than other sections of the arm  8608 . Other examples of any of the arm members described herein or in U.S. patent application Ser. No. 15/370,704 (Publ. No. 2017/0156823) may include an arm section (similar to arm section  8608   c ) that is wider than other sections of the arm. 
       FIGS. 87 and 88  show an example configuration in which the attachment portion is coupled to the anchor (not shown in  FIG. 87 ) by a single connector, or directly via multiple connectors. 
       FIG. 89  shows further examples of arms  8909 ,  8914 ,  8915  and  8922 - 8930  that include a spring member with a shape having at least two open loop portions arranged adjacent each other in a horizontal direction (direction generally parallel to the length dimension of the anchor  8933 ), forming an “S” shape laying in that horizontal direction.  FIG. 89  also shows examples of arms  8910 ,  8912 , and  8917 - 8921  that include a spring member with a shape having at least two open loop portions arranged adjacent each other in a vertical direction (direction generally perpendicular to the length dimension of the anchor  8933 ), forming one or more “S” shapes in that perpendicular direction.  FIG. 89  shows a further example of an arm  8911  having a “U” shaped spring member  8911   b . A further example of an arm  8913  in  FIG. 89  has a spring member  8913   b  formed of two right angle bends along the length dimension of the arm. 
     In any of the examples described herein, the width dimensions of the arm or of one or more selected portions of the arm) may be selected to provide one or more of a desired flexibility, bias force magnitude, bias force direction, durability or other characteristics. For example, the arms  8915  and  8916  have a similar shape, but the width dimension of the arm  8915  is greater than the width of the arm  8916 . As another example, the arms  8922 ,  8923  and  8924  in  FIG. 89  have a similar shape, but the width dimension of the arm  8924  is greater than the width of the arm  8923 . Similarly, the width dimension of the arm  8923  is greater than the width of the arm  8922 . In further examples, as an alternative or in addition to varying width dimensions, one or more of the arms (or selected portions of the arms) may have a varying thickness dimension (in the dimension into and out of the plane of the page of  FIG. 89 ), for a desired flexibility, bias force magnitude or direction, durability or other characteristic. In certain examples, the arms may be made smaller in width or thickness dimension (or both) relative to the anchor  8933  from which they extend, such that the anchor  8933  may provide a more rigid anchorage, while the arms provide a desired flexibility and resilience. Width or thickness dimension variances may be provided by any suitable process, including but not limited to machining, molding, laser cutting, 3D printing, or sinker EDM (Electronic Discharge Machining) to vary thickness of portions of an appliance member cut from a sheet. Alternatively or in addition to selecting or varying width or thickness dimensions, the arm length may be selected to provide or contribute to a desired flexibility, bias force, magnitude or direction, durability or other characteristic. 
     As another example, the arms  8925 ,  8926  and  8927  in  FIG. 89  have a similar shape relative to each other, but the width dimension of the arm  8927  is greater than the width of the arm  8926 , which is greater than the width of the arm  8925 . As yet another example, the arms  8928 ,  8929  and  8930  in  FIG. 89  have a similar shape relative to each other, but the width dimension of the arm  8930  is greater than the width of the arm  8929 , which is greater than the width of the arm  8928 . Each of the example arms  8909 - 8930  shown in  FIG. 89  has a uniform width dimension that is constant over the entire arm. In other examples, the width dimension of one or more portions of any of the arms  8900 - 8932  may be made greater or smaller than the width dimension of one or more other portions of the same arm. 
       FIG. 90  shows further examples of two adjacent arms  9031  and  9032  extending from an anchor  9033  of an appliance, appliance member (or a portion of an appliance or appliance member). Each arm  9031  and  9032  extends to an associated bracket connector (or male connector element)  9031   a  or  9031   b . Each of the arms  9031  and  9032  include a spring member  9031   b  or  9032   b , and an arm section  9031   c  or  9032   c  extending from the spring member to the bracket connectors  9031   a  or  9032   a.    
     The bracket connector  9031   a  is configured to be connected to a bracket secured to a first tooth  9034  in a patient&#39;s jaw, and the bracket connector  9032   a  is configured to be connected to a bracket secured to a second tooth  9035  in the patient&#39;s jaw. The first tooth  9034  and the second tooth  9035  may be adjacent teeth in the patient&#39;s jaw. In other examples, one or more other teeth (or extracted teeth locations) may be located between the first tooth  9034  and the second tooth  9035 . In one example, the tooth  9034  may be a canine tooth, while the tooth  9035  may be a second pre-molar. In other examples, the teeth  9034  and  9035  may be other teeth in a patient&#39;s jaw (upper jaw or lower jaw). 
     In certain examples, the arm configuration may be selected to provide one or more of a desired flexibility, bias force magnitude, bias force direction, durability or other characteristics. For example, arms configured according to examples  8600  and  8601  may provide sufficient force (magnitude and direction) for providing some, but a limited amount of movement in occlusogingival direction or a buccolingual direction, when the appliance is installed. Arms configured according to examples  8602 ,  8603  and  8604  may provide sufficient force (magnitude and direction) to move extrude or to move in occlusogingival direction. Arms configured to be relatively rigid may be employed when the tooth to be connected to the arm is not to be moved (or moved by a limited amount) and may be used for anchorage. In certain examples, arms configured according to examples  8606 ,  8607  and  8608  may be used in extraction cases to apply a force closer to the center of resistance of the teeth and to prevent the teeth from tipping, as the arm section  8606   c ,  8607   c  and  8608   c  in those examples is formed wider than other portions of the arm, such that the arm can act as a power arm. 
     In certain examples, any of the arms in  FIG. 86, 89 or 90  (or other arms described herein) may be configured to provide a bias force direction and magnitude at a desired location along the length of the arm and, thus, at a desired location relative to the tooth structure of a patient. For example, the arms shown in  FIG. 90  may be configured to provide a force on one or both teeth  9034  and  9035  (when the bracket connectors  9031   a  and  9032   a  are connected to respective brackets on the teeth  9034  and  9035 ), where the force on each tooth is directed toward the adjacent tooth. In particular examples, the arms  9031  and  9032  are configured to apply the force on one or both teeth  9034  and  9035 , at a location along the length dimension of each tooth corresponding to a center of resistance location. In the drawing if  FIG. 90 , the teeth  9034  and  9035  are shown laterally adjacent to the respective arms  9031  and  9032 . However, it will be understood that, when the bracket connectors  9031   a  and  9032   a  are connected to brackets on the respective teeth  9034  and  9035 , each of the bracket connectors  9031   a  and  9032   a  will be placed on or directly adjacent to a surface of a respective tooth  9034  and  9035  on which a bracket (not shown in  FIG. 90 ) is secured, as described herein. 
     In the example in  FIG. 90 , the arm  9031  is configured such that the arm section  9031   c  extends generally parallel to, but laterally offset from an axis A 1  (the axis direction perpendicular to the length dimension of the anchor  9033  at the location at which the arm  9031  connects to the anchor  9033 ). Similarly, the arm  9032  is configured such that the arm section  9032   c  extends generally parallel to, but laterally offset from an axis A 2  (the axis direction perpendicular to the length dimension of the anchor  9033  at the location at which the arm  9031  connects to the anchor  9033 ). 
     More specifically, the arm section  9031   c  is laterally offset from the axis A 1 , in a direction to the left of A 1 , such that spring member  9031   b  of the arm  9031  and the axis A 1  are located between the arm section  9031   c  and the arm  9032 . Similarly, the arm section  9032   c  is laterally offset from the axis A 2 , in a direction to the left of A 2 , such that spring member  9032   b  of the arm  9032  and the axis A 2  are located between the arm section  9032   c  and the arm  9031 . In addition, the spring members  9031   b  and  9032   b  of the arms  9031  and  9032  are configured such that (when the arms  9031  and  9032  are connected to respective teeth  9034  and  9035 ) the arm  9031  imparts a force F 1  on the tooth  9034  in a direction toward the arm  9032 , and the arm  9032  imparts a force F 2  on the tooth  9035  in a direction toward the arm  9033 . The magnitude of the force F 1  and F 2  depend on one or more (or a combination of) the shape and configuration of the arms  9031  and  9032  (including the spring members  9031   b  and  9032   b ), the lateral spacing between the arms  9031  and  9033 , and the thickness and material of the arms  9031  and  9032 . 
     In the example in  FIG. 90 , the spring members  9031   b  and  9032   b  of the arms  9031  and  9032  are located adjacent (or relatively close to) the anchor  9033 . In addition, the length of the arm sections  9031   c  and  9032   c  may be configured to locate the anchor  9033  at or near the centers of resistance  9034   a  and  9035   a  of the respective teeth  9034  and  9035 . In that manner, the spring members  9031   b  and  9032   b  may be located at or near the centers of resistance  9034   a  and  9035   a  of the respective teeth  9034  and  9035  (to impart the force F 1  or F 2  on the tooth  9034  or  9035 , at or near the center of resistance  9034   a  or  9035   a  of the tooth  9034  or  9035 ). In other examples, the arms  9031  and  9032  may be configured to impart a force F 1  or F 2  on a tooth  9034  or  9035 , at a location that is spaced apart (e.g., vertically offset in the orientation of  FIG. 90 ) from the center of resistance  9034   a  or  9035   a  of the tooth  9034  or  9035 , by a specified distance. In such other examples, the force F 1  or F 2  can have a lever-like action on a tooth  9034  or  9035 , where the center of resistance acts as a fulcrum. The center of resistance of a tooth may depend on various factors, including the depth and angle of the root of the tooth, type of tooth or other factors. In particular examples described herein, an appliance (or method) may include one or more arms that are configured to impart one or more forces on one or more teeth, where the direction, and magnitude of the force or forces may be selected, and the location of the force (relative to a center of resistance of the tooth) may be selected based, in part, on the configuration of the arm (including, for example, the configuration of the spring member  9031   b ,  9032   b , the distance and location of the spring member relative to the anchor  9033 , and the length of the arm section  9031   c ,  9032   c ). 
     Each of the example arms  8600 - 8608  in  FIG. 86  and arms  9031  and  9032  in  FIG. 90  is shown as extending to (being formed integral with or coupled to) to a bracket connector  100   a - 108   a  that has an annular or ring shape and in particular, a square, annular shape (having a generally square-shaped outer perimeter and a generally square-shaped opening). In other examples, an annular or ring-shaped bracket connector may have a generally round or rounded shape, an oval shape (having a round or oval outer perimeter and a round or oval opening) or other suitable shape. 
     Each of the example arms  8909 - 8930  in  FIG. 89  extends to a bracket connector  8900   a - 8908   a  that has a T shaped configuration. In certain examples, such T shaped bracket connectors may correspond to the T shaped male connector elements as described in U.S. patent application Ser. No. 15/370,704 (Publ. No. 2017/0156823) (such as those identified by reference numbers 1802, 1822, or 2500 in that publication). 
     In other examples, any of the arms described with regard  FIGS. 86 and 90  may extend to (be formed integral with or coupled to) a T shaped bracket connector of  FIG. 89 , or any of the other bracket connectors (or male connector elements) described herein or in U.S. patent application Ser. No. 15/370,704 (Publ. No. 2017/0156823), in place of the bracket connectors  8600   a - 8608   a . Similarly, in other examples, any of the arms described with regard  FIG. 89 , may extend to an annular or ring shaped bracket connector described in regard to the examples of  FIG. 86 , or any of the other bracket connectors (or male connector elements) described herein or in U.S. patent application Ser. No. 15/370,704 (Publ. No. 2017/0156823), in place of the bracket connectors  8909   a - 8930   a.    
       FIGS. 91 and 92  show certain examples of Z embodiment features, including a rigid bar ( 9130  in  FIGS. 91 and 9240  in  FIG. 92 ) having loop or curved features ( 9131 - 9138  in  FIGS. 91 and 9241-9248  in  FIG. 92 ) according to various examples, between associated pairs of bracket connectors (or male connector elements). 
     Each of the loop or curved features  9131 - 9138  and  9241 - 9248  in  FIGS. 91 and 92  includes a pair of linear arm sections coupled by one or more curved sections. For example, the loop or curved feature  9131  in  FIG. 91  includes first and second linear arm sections  9131   a  and  9131   b  that extend from the rest of the rigid bar  9130  to a curved section  9131   c . In each of the examples in  FIGS. 91 and 92 , both of the first and second arm sections of the loop or curved feature is larger (e.g., wider) in at least one dimension than the corresponding dimension of the curved section of that feature. For example, each of the linear arm sections  9131   a  and  9131   b  of the loop or curved feature  9131  in  FIG. 91  has a larger (e.g., wider) dimension than the corresponding dimension (width) of the curved section  9131   c  of that feature  9131 . 
     In other examples, one, but not both of the first and second arm sections of any of the loop or curved features  9131 - 9138  or  9241 - 9248  may be formed larger (e.g., wider) in at least one dimension than the corresponding dimension of the curved section. In other examples, the curved section of any of the features  9131 - 9138  or  9241 - 9248  may be formed to be larger (e.g., wider) in at least one dimension than the corresponding dimension of one or both of the arm sections. This can allow the appliance to apply a force closer to the center of resistance of the tooth (or any desired location along the length of the tooth, based on the location of the larger or wider section). In yet other examples, the first and second linear arm sections and the curved section of any of the features  9131 - 9138  or  9241 - 9248  may be formed to have a uniform or constant corresponding dimension (e.g., width). 
     The loop or curved feature  9131  includes a curved section  9131   c  having a generally U shaped portion  9131   d  (an inverted U in the orientation of  FIG. 91 ), and two laterally extended curved loop portions  9131   e  and  9131   f  (located on the two respective sides of the U shaped portion  9131   d ). The U shaped portion  9131   d  extends along and between the first and second arm sections  9131   a  and  9131   b . The curved loop portion  9131   e  connects one end of the U shaped portion  9131   d  to the first arm section  9131   a , while the curved loop portion  9131   f  connects the other end of the U shaped portion  9131   d  to the second arm section  9131   b . Each of the curved loop portions  9131   e  and  9131   f  has a rounded closed end that is wider (in the horizontal dimension of  FIG. 91 ) than the rest of the curved loop portion of the feature  9131 . The wider, rounded end ( 9131   e ′ and  9131   f ) can provide increased flexibility while decreasing risk of fracture. 
     The loop or curved feature  9132  has a configuration that is similar to the configuration described with regard to feature  9131 . For example, the loop or curved feature  9132  may include first and second linear arm sections  9132   a  and  9132   b , and a curved section  9132   c  having a U shaped portion  9132   d  and curved loop portions  9132   e  and  9132   f  (corresponding to sections  9131   a ,  9131   b  and  9132   c  and portions  9131   d ,  9131   e  and  9131   f  of feature  9131 ). However, the U shaped portion  9132   d  of the loop or curved feature  9132  is smaller than the U shaped portion  9131   d  of the loop or curved feature  9131 . In the examples in  FIG. 91 , the U shaped portion  9131   d  extends along about seventy-five percent of the length of the first and second arm sections  9131   a  and  9131   b , while the U shaped portion  9132   d  extends along about twenty-five percent of the length of the first and second arm sections  9132   e  and  9132   f . In other examples, the U shaped portion  9131   d  or  9132   d  may extend along any suitable portion of the length of the first and second arm sections. A longer U shaped portion (such as shown at  9131   d ) may be more flexible than a shorter U shaped portion (such as shown at  9132   d ). 
     Another example of a loop or curved feature  9133  also includes first and second linear arm sections  9133   a  and  9133   b  and a curved section  9133   c  (for example, corresponding to the arm sections  9131   a  and  9131   b  and curved section  9131   c  of the feature  9131 ). However, the linear arm sections  9133   a  and  9133   b  are smaller in length than the linear arm sections  9131   a  and  9131   b  of feature  9131 . The linear arm sections of any of the loop or curved features  9131 - 9138  or  9241 - 9248  may be of any suitable length (or have different lengths for first and second arm sections). The length of the linear arm section of a loop or curved feature can at least partially determine an amount of force applied to adjacent teeth. 
     The curved section  9133   c  of the loop or curved feature  9133  has a generally U shaped portion  9133   d  (an inverted U in the orientation of  FIG. 91 ), and two laterally extended curved loop portions  9133   e  and  9133   f  (located on the two respective sides of the U shaped portion  9133   d ). However, the generally U shaped portion  9133   d  has an enlarged section  9133   d ′ adjacent where the curved loop portions  9133   e  and  9133   f  connect to the generally U shaped portion  9133   d . The enlarged section  9133   d ′ is larger (e.g., wider) in at least one dimension (the horizontal dimension in the orientation of  FIG. 91 ) than the rest of the generally U shaped portion  9133   d . The curved loop portions  9133   e  and  9133   f  correspond, generally to the curved loop portions  9131   e  and  9131   f  of feature  9131 . However, the curved loop portion  9133   e  does not extend laterally beyond the left side of the first arm section  9133   a , and the curved loop portion  9133   f  does not extend laterally beyond (or as far beyond) the right side of the second arm section  9133   b , relative to lateral extension of the curved or loop portions  9131   e  and  9131   f . The narrower profile provided by the curved loop portions  9133   e  and  9133   f  (relative to the curved or loop portions  9131   e  or  9131   f ) can be beneficial in contexts in which bracket connectors are closer together (for example, for anterior teeth or other contexts in which space in the mesiodistal dimension or lateral width dimension is limited). 
     Another example of a loop or curved feature  9135  also includes first and second linear arm sections  9135   a  and  9135   b  and a curved section  9135   c . The linear arm sections  9135   a  and  9135   b  are similar to the linear arm sections  9133   a  and  9133   b  of the feature  9133 . However, the curved section  9135   c  has a C shape or an open circle shaped portion  9135   d  (having a shape of a circle with an open edge), instead of a U shape described for feature  9133 . The curved section  9135   c  also has two laterally extended curved loop portions  9135   e  and  9135   f  (corresponding to curved loop portions  9133   e  and  9133   f  of feature  9133 ) located on the two respective sides of the C shape portion  9135   d.    
     Another example of a loop or curved feature  9134  also includes first and second linear arm sections  9134   a  and  9134   b  and a curved section  9134   c . The linear arm sections  9134   a  and  9134   b  are similar to the linear arm sections  9133   a  and  9133   b  of the feature  9133 . However, the curved section  9134   c  has a C shape or an open circle shape (shape of a circle, with an open edge). The radius of the circle shape of the curved section  9134   c  may be selected to provide a desired performance characteristic. For example, each of the loop or curved features  9136 ,  9137  and  9138  has a shape and configuration similar to that of the loop or curved feature  9134 , but with a circle shape having a different diameter. More specifically, the loop or curved feature  9136  includes first and second linear arm sections  9136   a  and  9136   b  and a curved section  9136   c  that has a smaller diameter than the curved section  9134   c  of feature  9134 . Similarly, the loop or curved feature  9137  includes first and second linear arm sections  9137   a  and  9137   b  and a curved section  9137   c  that has a smaller diameter than the curved section  9136   c  of feature  9136 . Similarly, the loop or curved feature  9138  includes first and second linear arm sections  9138   a  and  9138   b  and a curved section  9138   c  that has a smaller diameter than the curved section  9137   c  of feature  9137 . A smaller diameter may be beneficial in certain contexts, for example, for certain types of teeth or where space in the lateral width dimension is limited. 
     Another example of a loop or curved feature  9241  in  FIG. 92  has a configuration having some similarities to the configuration of the loop or curved feature  9131  in  FIG. 91 . In particular, the loop or curved feature  9241  includes first and second linear arm sections  9241   a  and  9241   b  and a curved section  9241   c . The linear arm sections  9241   a  and  9241   b  are similar to the linear arm sections  9131   a  and  9131   b  of the feature  9131 . Also, the curved section  9241   c  has a generally U shaped portion  9241   d  (similar to the generally U shaped portion  9131   d  of feature  9131 ). However, the curved section  9241   c  of the feature  9240  has two laterally extended curved loop portions  9241   e  and  9241   f  that each have a C shape or an open circle shape (shape of a circle, with an open edge), instead of a curved loop shape of feature  9131 . The loop or curved feature  9248  has a similar configuration as the loop or curved feature  9241 . 
     Another example of a loop or curved feature  9245  in  FIG. 92  has a configuration having some similarities to the configuration of the loop or curved feature  9131  in  FIG. 91 . In particular, the loop or curved feature  9245  includes first and second linear arm sections  9245   a  and  9245   b  and a curved section  9245   c . The linear arm sections  9245   a  and  9245   b  are similar to the linear arm sections  9131   a  and  9131   b  of the feature  9131 . Also, the curved section  9245   c  has a generally U shaped portion  9245   d  (corresponding to the generally U shaped portion  9131   d  of feature  9131 ). However, the generally U shaped portion  9245   d  has an enlarged section  9245   d ′ at the closed end of the U shaped portion  9245   d , and a second enlarged section  9245   d ″ where curved loop portions  9245   e  and  9245   f  connect to the generally U shaped portion  9245   d . The enlarged sections  9245   d ′ and  9245   d ″ are each larger (e.g., wider) in at least one dimension (the horizontal dimension in the orientation of  FIG. 92 ) than other sections of the generally U shaped portion  9245   d . The curved loop portions  9245   e  and  9245   f  correspond, generally to the curved loop portions  9131   e  and  9131   f  of feature  9131 . 
     Another example of a loop or curved feature  9246  in  FIG. 92  has a configuration corresponding to the configuration of feature  9245  (including first and second arm sections  9246   a ,  9246   b  and a curved section  9246   c  having a generally U shaped portion  9246   d  similar to corresponding parts of the feature  9245 ). However, the loop or curved feature  9246  has curved loop portions  9246   e  and  9246   f  that correspond in shape to the curved loop portions  9241   e  and  9241   f  of feature  9241 . 
     Another example of a loop or curved feature  9247  in  FIG. 92  has a configuration corresponding to the configuration of feature  9241  (including first and second arm sections  9247   a ,  9247   b  and a curved section  9247   c  having curved loop portions  9247   e  and  9247   f  that correspond in shape to the curved loop portions  9241   e  and  9241   f  of feature  9241 ). However, the curved section  9247   c  of the loop or curved feature  9247  has a C shape or an open circle shaped portion  9247   d  (having a shape of a circle with an open edge), instead of a generally U shape described for feature  9241   d.    
     Other examples of loop or curved features  9242 ,  9243  and  9244  in  FIG. 92  also include first and second linear arm sections and a curved section. The curved sections of each of the loop or curved features  9242 ,  9243  and  9244  include various combinations of generally U shaped portions and C or open circle shaped portions, configured to provide a desired flexibility, a bias or spring force in one or more directions (or both), a force magnitude, durability, or other characteristics. 
       FIG. 93A  is a plan view of a planar version of an orthodontic appliance configured in accordance with embodiments of the present technology, and  FIG. 93B  is a treatment configuration of the appliance shown in  FIG. 93A . 
       FIG. 94  depicts an orthodontic appliance configured in accordance with embodiments of the present technology, shown installed in a patient&#39;s mouth. 
     IV. Selected Devices, Systems, and Methods for Tooth Attachment 
     According to some aspects of the present technology, one or more portions of the orthodontic appliances and/or securing members disclosed herein may be configured to have a low profile (e.g., in a dimension extending away from the tooth, including the buccolingual, mesiodistal, and/or occlusogingival directions). A lower profile can improve the patient&#39;s experience, as the appliance and/or securing member will typically be less perceptible to the patient and less likely to agitate surrounding tissue. 
       FIG. 95 , for example, shows a low-profile attachment portion  9540  configured in accordance with embodiments of the present technology. In  FIG. 95 , the attachment portion  9540  is depicted coupled to a serpentine biasing portion  9550  that, together with the attachment portion  9540 , comprises an arm  9530  that extends from anchor  9520 . It will be appreciated that the attachment portion  9540  may be used with any of the arm configurations described herein, and/or can be coupled to any of the biasing portions and/or connectors described herein. 
     As shown in  FIG. 95 , the attachment portion  9540  can comprise a base  9551  and first and second arms  9556   a ,  9556   b  (collectively “arms  9556 ”) coupled to and extending laterally away from the base  9551 . The base  9551  may comprise a proximal region  9552  proximal of where the arms  9556  connect to the base  9551  and a distal region  9554  distal to where the arms  9556  connect to the base  9551  (as well as distal to the proximal region  9552 ). The first arm  9556   a  may be disposed at a first angle θ 1  relative to the base  9551 , and the second arm  9556   b  may be disposed at a second angle  62  relative to the base  9551 . The base  9551  may extend in a first direction A 1  and the arms  9556  may extend in a second direction A 2  that is angled relative to the first direction A 1 . In some embodiments, the arms  9556  extend away from the base  9551  at substantially the same longitudinal location and/or at substantially the same angle. In some embodiments, the arms  9556  extend away from the base  9551  at different longitudinal locations and/or at different angles. 
     The first and second angles θ 1 , θ 2  can be the same as or may differ from one another. In some embodiments, the first angle θ 1  is (i) at least 30 degrees, (ii) no more than 120 degrees, or (iii) within a range of from 30-120 degrees, or any incremental value between one of these ranges (e.g., 35 degrees, 90 degrees, 110 degrees, etc.). In these and other embodiments, the second angle θ 2  is (i) at least 30 degrees, (ii) no more than 120 degrees, or (iii) within a range of from 30-120 degrees, or any incremental value between one of these ranges (e.g., 35 degrees, 90 degrees, 110 degrees, etc.). In some embodiments, the first region  9554  is generally orthogonal to the second region  9556 . 
     As described herein, the attachment portion  9540  is configured to detachably couple the arm  9530  to a securing member disposed on a patient&#39;s tooth. The attachment portion  9540  may be configured to engage the securing member in such a way that substantially inhibits longitudinal (e.g., translational) and/or rotational movement of the attachment portion  9540  relative to the corresponding securing member. Accordingly, the appliances of the present technology may efficiently transfer all or substantially all of the force provided by the arm (such as arm  9530 ) to a tooth via a corresponding securing member. By limiting or inhibiting movement of the attachment portion  9540  relative to the corresponding securing member, the appliances of the present technology are configured to move teeth with less force than is necessary with traditional braces. 
       FIGS. 96 and 97  are isometric views of example securing members  9600 ,  9700  configured for use with the appliances of the present technology. The arms and/or attachment portions described herein may be configured to detachably couple one or both securing members  9600 ,  9700  to secure the appliance to the patient&#39;s dentition during treatment. As shown in  FIG. 96 , the securing member  9600  may include a base  9610  and coupling arms  9680   a ,  98680   b  (collectively “coupling arms  9680 ”) coupled to the base  9610 . The base  9610  may comprise a first side  9612  on which the coupling arms  9680  are disposed, and a second side  9614  configured to be directly or indirectly coupled to one or more of the patient&#39;s teeth, e.g., via an adhesive such as a composite resin. The base  9610  can be coupled to the patient&#39;s tooth such that the coupling arms  9680  are disposed in a generally vertical orientation (e.g., an occlusal-gingival direction). In some embodiments, the base  9610  can be coupled to the patient&#39;s teeth such that the coupling arms  9680  may be disposed in another orientation, such as a horizontal orientation (e.g., a mesial-distal direction) or diagonal orientation (e.g., a partial mesial-distal direction or partial occlusal-gingival direction). In some embodiments, the coupling arms  9680  may be disposed at the same angle and/or different angles from one another. The surface of the second side  9614  can be generally flat and/or roughened to increase its surface area for enhanced bonding to the one or more of the patient&#39;s teeth. In some embodiments, the surface of the second side  9614  can have a shape or slope that generally complements that of the one or more of the teeth the base  9610  is configured to be coupled to, such as a lingual face of the one or more of the patient&#39;s teeth. The base  9610  can include a boundary or perimeter  9616  within which the one or more coupling arms  9680  are generally within. In some embodiments, the securing member  9600  may be a commercially available 2D® Lingual bracket (Bernhard Foerster GmbH). 
     Each coupling arm  9680   a ,  9680   b  can include a base portion  9622   a ,  9622   b  (collectively “base portions  9622 ”) fixed to the base  9610  (e.g., via an adhesive, weld, solder, etc.), and a coupling portion  9624   a ,  9624   b  (collectively “coupling portions  9624 ”) extending from the base portion  9622 . When disposed within a patient&#39;s mouth, the coupling portions  9624  may be farther from the patient&#39;s gingiva than the base portions  9622 . Each of the coupling portion  9624  can include a curved surface that is spaced apart from the first side  9612  of the base  9610 , or other configuration that generally resembles a hook or similar shape. In some embodiments, the coupling portions  9624  can be sufficiently flexible, plastic and/or deformable such that the coupling portion  9624   s  can be temporarily moved from a closed state to an open state in which an attachment portion (such as attachment portion  9540 ) can be moved into position under the coupling portions  9624 . 
     As depicted in  FIG. 97 , securing member  9700  can have similar features to securing member  9700  shown in  FIG. 96 . For example, the securing member  9700  can comprise a base  9710  having a first side  9712 , a second side  9714 , and a perimeter  9716 . A coupling arm  9780  comprising a base portion  9722  and a coupling portion  9724  can be disposed on the first side  9712  of the base  9710 . As shown in  FIGS. 96 and 97 , the securing members  9600  and  9700  can include two coupling arms  9680  or a single coupling arm  9780 . In some embodiments, the securing members of the present technology can include more than two coupling arms (e.g., three coupling arms, four coupling arms, etc.). 
       FIGS. 98A-D  are isometric, front, top, and side views, respectively, of the attachment portion  9540  shown in  FIG. 95  and the securing member  9600  shown in  FIG. 96 , configured in accordance with embodiments of the present technology. Referring first to  FIG. 98A , the coupling portions  9624  the coupling arms  9680  are disposed over the second region  9556  of the attachment portion  9540 , with one of the coupling arms  9680  disposed over the second region  9556  on a first side of the first region  9554  and the other of the coupling arms  9680  disposed over the arms  9556  on a second, opposing side of the distal region  9554 . In some embodiments, when the appliance is disposed adjacent the patient&#39;s teeth and the attachment portion  9540  is secured to the securing member  9600 , (i) the arms  9556  extend in a generally mesial-distal direction under the coupling arms  9680 , and (ii) the distal region  9554  extends in a generally occlusal-gingival direction and abuts (e.g., is proximate to) a portion of the coupling arms  9680 . In doing so, the securing member  9600  and the configuration of the attachment portion  9540  prevents or inhibits longitudinal and/or rotational movement of the attachment portion  9540  relative to the securing member  9600 , e.g., in or about the occlusal-gingival direction (as indicated by axis A 1 ), the mesial-distal direction (as indicated by axis A 2 ), and/or lingual-facial direction (as indicated by axis A 3 ). As a result, when an appliance is attached to a patient&#39;s teeth via the securing member  9600 , the particular magnitude and directional force provided via each of the arms  9530  may be substantially entirely translated to the respective tooth. Moreover, because the magnitude and directional force provided via each of the arms  9530  may be substantially entirely translated to the respective tooth, movement of the tooth from an original tooth arrangement to final tooth arrangement can be achieved with less magnitude than may otherwise be required. 
     Each of the coupling arms  9680  can comprise a side surface  9625   a ,  9625   b  (collectively “side surfaces  9625 ”) configured to be positioned in apposition to of the distal region  9554  and/or proximal region  9552  of the attachment portion  9540  such that the coupling arms  9680  are spaced apart from one another by the distal region  9554  and/or proximal region  9552 . As shown in  FIGS. 98B and 98C , when the attachment portion  9540  is coupled to the securing member  9600 , the side surfaces  9625  of the coupling arms  9680  may be in apposition with the attachment portion  9540 . In some embodiments, the attachment portion  9540  may be in direct contact with one or both of the coupling arms  9680 , or spaced apart from one or both of the coupling arms  9680  by no more than a predetermined distance, e.g., to ensure longitudinal movement and/or rotation of the securing member  9600  relative to the attachment portion  9640  is sufficiently inhibited. The predetermined distance may, for example, be less than about 0.01 millimeters (mm), about 0.1 mm, about 1 mm, about 2 mm, or about 3 mm, or any incremental value between about 0.01 to 3 mm. Apposition of the coupling arm  9680  with the attachment portion  9540  can help ensure the magnitude and directional force (e.g., provided at least partially along or about the mesial-distal axis and/or about the occlusal-gingival axis) provided via the arm  9530  is substantially translated to the respective tooth when the appliance is implanted adjacent a patient&#39;s teeth and coupled to the securing member  9600 . 
     As shown in  FIG. 98C , a thickness of each of the distal region  9554  and the arms  9556  of the attachment portion  9540  can be generally the same. In some embodiments, the thickness of the distal region  9554  and the arms  9556  may differ from one another, e.g., with the distal region  9554  having a greater thickness than that of the arms  9556 , or vice versa. The thickness of the base  9610  of the securing member  9600  may be generally less than that of the attachment portion  9540  and/or coupling arm  9680 . As also shown in  FIG. 9C , the distal region  9554  and the arms  9556  are positioned in close proximity to the base  9610 , which can inhibit movement of the attachment portion  9540  relative to the securing member  9600  in the lingual-facial direction and/or about the mesial-distal axis. 
       FIG. 98D  is a side view of the attachment portion  9540  and securing member  9600  shown in  FIGS. 98A-98C . As shown in  FIG. 98D , the coupling arm  9680  may be configured to be positioned in apposition with the first side  9612  of the base  9610 . A surface  9625   c  of the coupling arm  9680  at one end (e.g., an occlusal end) adjacent the base  9610 , and/or a surface  9625   d  of the coupling arm  9680  at another end (e.g., a gingival end) adjacent the base  9610 , may each abut the first surface  9612  of the base  9610 . As also shown in  FIG. 98D , the coupling arm  9680  can be configured to be positioned in apposition with portions of the arms  9556  of the attachment portion  9540 . That is, an innermost surface  9625   e  of the coupling portion  9624  of the coupling arm  9680  may abut the arms  9556  of the attachment portion  9540 . Positioning the coupling arms  9680  around the arms  9556  in such a manner may inhibit movement of the attachment portion  9540  relative to the securing member  9600 , e.g., in the occlusal-gingival direction and/or about the mesial-distal axis. 
     Still referring to  FIG. 98D , the second side  9614  of the base  9610  may be configured to be positioned against and/or fixed to one or more of the patient&#39;s teeth. For example, in some embodiments the second side  9614  may be fixed to a lingual or buccal face of the one or more of the patient&#39;s teeth. As such, the base  9610 , and more generally the securing member  9600  and attachment portion  9540 , can be at least partially disposed in the occlusal-gingival direction (e.g., with a vertical orientation) when the attachment portion  9540  is secured to the securing member  9600 . For example, the securing member  9600  and attachment portion  9540 , or portions thereof, may be disposed to be generally parallel to the lingual or buccal surface of the one or more of the patient&#39;s teeth. 
       FIGS. 99-104  are front views of various embodiments of an attachment portion and a securing member, configured in accordance with embodiments of the present technology. An attachment portion of the present invention can be configured to be coupled to a securing element such as securing member  9600  with multiple coupling arms  9680 , securing member  9700  with a single coupling arm  9780 , or another suitable coupling configuration. An attachment portion shown and described with reference to  FIGS. 99-104  may be part of a respective arm (e.g., the arm  9530 ) of an appliance as described elsewhere herein. Additionally, each of the attachment portions described with reference to  FIGS. 99-104  may be configured to inhibit or prevent longitudinal movement and/or rotation of the attachment portion relative to the corresponding securing member, such that the load and/or direction applied via the attachment portion is substantially translated to the patient&#39;s teeth via the corresponding securing member. The attachment portions shown and described with reference to  FIGS. 99-104  accomplish this at least in part by abutting or placing in contact regions of the attachment portion with surfaces of the corresponding securing member  9600  or  9700 . 
     Attachment portion  9940  shown in  FIG. 99  can be configured to minimize translation and/or rotation of the attachment portion  9940  relative to a corresponding securing member such as securing member  9600 . The attachment portion  9940  can have a generally rectangular shape defined by an inner perimeter  9902  and an outer perimeter  9904  that together define a width of the rectangular shape. The attachment portion  9940  can comprise a distal region  9956   a , lateral regions  9956   b ,  9956   c , and/or a proximal region  9956   d  (collectively “regions  9956 ). In some embodiments, the attachment portion  9940  can have a framed portion  9970  between regions  9956   a ,  9956   b ,  9956   c , and  9956   d . A distal arm  9954  can extend distally from distal region  9956   a  and be configured to be positioned between coupling arms  9680 . Accordingly, the distal arm  9954  can be configured to engage an inner surface  9625   a  and/or  9625   b  of at least one coupling arm  9680  to prevent excessive lateral translation of the attachment portion  9940  relative to securing member  9600 . Similarly, lateral region  9956   b  and/or  9956   c  can be configured to engage an outer surface  9662  of a coupling arm  9680  to prevent excessive lateral translation of the attachment portion  9940 . The lateral regions  9956   b  and/or  9956   c  meet the distal arm  9954  to form a shoulder region that may be configured to limit proximal and/or distal translation of the attachment portion  9940 . In some embodiments, a proximal arm  9964  can extend proximally from proximal region  9956   d.    
     According to some embodiments, coupling arms  9680  can be configured to be spaced apart from the attachment region  9940  as shown in  FIG. 99 . In some embodiments, one or more regions of the attachment portion  9940  can be configured to contact one or more regions of the securing member  9600 . For example, a portion of the inner perimeter  9902  of the lateral regions  9956   b ,  9956   c  of the attachment portion  9940  can be configured to contact a corresponding outer surface  9962   a ,  9962   b  of the securing member  9600  when the attachment portion  9940  is coupled to the securing member  9600 . 
       FIG. 100  depicts an embodiment of an attachment portion  10040  with multiple distal arms  10054  configured to further limit lateral translation of the attachment portion  10040  relative to the securing member  9600 . As shown in  FIG. 100 , the attachment portion  10040  may include the distal, lateral, and proximal regions  10056   a ,  10056   b ,  10056   c ,  10064 , such as the regions  9956  described with reference to  FIG. 99 . In some embodiments, the attachment portion  10040  can have two distal arms  10054  as shown in  FIG. 100 . In some embodiments, the attachment portion  10040  can include more than two distal arms  10054 . According to some aspects of the present technology, for example as shown in  FIG. 100 , distal arms  10054  can be configured to be spaced apart from or positioned in close proximity to outer surfaces  9662  of the coupling arms  9680 . Distal arms  10054 , distal region  10056   a , and/or lateral regions  10056   b ,  10056   c  can be configured to engage coupling arms  9680  of the securing member  9600  to limit translation and/or rotation of the attachment portion  10040  relative to the securing member  9600 . 
     In some embodiments, for example as shown in  FIG. 101 , an attachment portion  10140  can include multiple framed portions  10170 ,  10172  configured to surround the coupling arms  9680  of the securing member  9600  in order to further limit proximal and/or distal translation of the attachment portion  10140  relative to the securing member  9600 . The attachment portion  10140  shown in  FIG. 101  includes a distal region  10156   a , lateral regions  10156   b ,  10156   c , and a proximal region  10156   d  (collectively “regions  10156 ”), as previously described. Additionally, the attachment region  10140  has an intermediate region  10156   e  extending between lateral regions  10156   b ,  10156   c  and positioned between the distal region  10156   a  and the proximal region  10156   d . The intermediate region  10156   e  can be configured to be positioned adjacent the coupling regions  9624  of the coupling arms  9680  of the securing member  9600 . As previously described in reference to  FIGS. 99 and 100 , regions  10156  can be configured to be in contact with or adjacent to the coupling arms  9680  based on a desired security of the coupling. By positioning regions  10156  adjacent to each surface of the coupling arms  9680 , the attachment portion  10140  can be configured to inhibit translation and/or rotation of the attachment portion  10140  relative to the securing member  9600 . Proximal arm  10164  can extend proximally from the proximal region  10156   d  and can couple to a connector of the present technology to form an arm as described elsewhere herein. 
     Embodiments of the present technology illustrated in  FIGS. 102-104  include securing members  9700  having a single couple arm  9780 . Referring first to  FIG. 102 , the attachment portion  10240  may include a distal region  10256   a , lateral regions  10256   b ,  10256   c , and a proximal region  10256   d  (collectively “regions  10256 ”). The attachment portion  10240  can be attached to a connector of the present technology to form an arm via a proximal protrusion  10264 . The attachment portion  10240  can include distal arms  10254   a ,  10254   b  extending distally from distal portion  10256   a . The distal arms  102  can be configured to engage surfaces  9756   a ,  9756   b  of the coupling arm  9780  to limit lateral translation of the attachment portion  10240  relative to the securing member  9700 . Although the attachment portion  10240  is depicted with regions  10256  spaced apart from the coupling arm  9780 , in some embodiments one or more regions  10256  can be configured to be in direct contact with the coupling arm  9780 . 
     An attachment portion configured for use with a securing member with a single coupling arm  9700 , for example attachment portion  10340  shown in  FIG. 103 , can comprise multiple framing regions  9770  such that when the attachment portion  10340  is coupled to the securing member  9700 , each surface of the coupling arm  9780  of the securing member  9700  abuts a region of the attachment portion  10340  reduce translation of the attachment portion  10340 . The attachment portion  10340  can include a distal region  10356   a , a proximal region  10356   d , and an intermediate region  10356   e  positioned between the distal region  10356   a  and the proximal region  10356   d  (collectively “regions  10356 ”). Each of the distal, proximal, and intermediate regions  10356   a ,  10356   d ,  10356   e  may extend between lateral regions  10256   b ,  10256   c , as shown in  FIG. 103 . In some embodiments, each region of the attachment portion  10340  may be configured to abut a corresponding surface of the coupling arm  9780  to provide a limit to translation of the attachment region  10340 . For example, the distal region  10356   a  and the proximal region  10356   d  can be configured to be positioned proximate a distal surface  9756   c  and a proximal surface  9756   d  of the coupling arm  9780 , respectively to limit proximal and/or distal translation of the attachment portion  10340 . Lateral regions  10356   b ,  10356   c  can abut lateral surfaces  9756   a ,  9756   b  of the coupling arm  9780  to limit medial and/or lateral translation of the attachment portion  10340 . Intermediate portion  10356   e  can abut an inner surface  9756   e  of the coupling arm  9780 , for example as depicted in  FIG. 98D , to limit proximal and/or distal translation of the attachment portion  10340 . In some embodiments, a size of the framing portions  9770 ,  9772  can be selected such that the regions  10356  are spaced apart from surfaces of the coupling arm  9780  when coupled to the securing member  9700 . Spacing, or a lack thereof, between the regions  10356  and the surfaces of the coupling arm  9780  may be based on an intended security of the coupling between the attachment portion  10340  and the securing member  9700 . 
     According to some embodiments, an attachment portion such as attachment portion  10440  shown in  FIG. 104  can be configured to contact a greater area of a securing member (e.g., securing member  10400 ) for enhanced security of the connection. In some embodiments, the securing member  10400  can have a generally rounded shape and a single coupling arm  10480  as depicted in  FIG. 104 . The attachment portion  10440  may have generally similar features to the attachment portion  10240  shown in  FIG. 102 . For example, the attachment portion  10440  may comprise a distal region  10456   a , lateral regions  10456   b ,  10456   c , and proximal region  10456   d  (collectively “regions  10456 ”). Together, the regions  10456  can define a framing region  10470 . The attachment portion  10440  can further comprise a proximal arm  10464  extending proximally from the proximal region  10456   d  and/or distal arms  10454   a ,  10454   b  extending distally from the distal region  10456   a . As shown in  FIG. 104 , the distal arms  10454   a ,  10454   b  may be positioned at an angle relative to the distal region  10456   a . In some embodiments the angle may be greater than 90 degrees (e.g., 95 degrees, 100 degrees, 105 degrees, 110 degrees, etc.). The angle can be increased in order to increase an area of the attachment portion  10440  such that when the attachment portion  10440  is coupled to the securing member  10400 , the attachment portion  10440  engages a greater area of the securing member  10400 , further inhibits translation of the attachment portion, and/or increases a security of the coupling. 
       FIG. 105  is an isometric view of a positioning device  10500  configured in accordance with embodiments of the present technology. The positioning device  10500  is configured to hold one or more securing members in a desired position relative to the patient&#39;s teeth to facilitate bonding of the securing members to the teeth in the desired position. In some embodiments, for example as shown in  FIG. 105 , the positioning device  10500  may comprise a first portion  10505  configured to be releasably secured to one or more of the patient&#39;s teeth, and one or more second portions  10510  coupled to the first portion  10505 , each configured to hold a securing member. The positioning device  10500  may include a cover configured to be disposed over all or a portion of the patient&#39;s teeth. In some embodiments, the cover generally conforms to the patient&#39;s dental topography to provide a snug fit. In some embodiments, the device  10500  is configured to be disposed over the patient&#39;s teeth T such that a surface of the device  10500  closest to the gingiva and adjacent a lingual surface of the patient&#39;s teeth T is positioned at an intermediate portion of the patient&#39;s teeth T (e.g., not at or below the patient&#39;s gingiva). 
     As shown in  FIG. 105 , the securing member  9600  corresponds to that shown and described with reference to  FIGS. 96 and 98A-98D . However, in some embodiments, the securing member  9600  can correspond to that shown in  FIG. 97 . Additionally, the securing member  9600  can correspond to any of the securing members described herein. In such embodiments, the second portion  10510  can have a shape configured to receive such a securing member. 
     The device  10500  can comprise a silicone, plastic, polymer, and/or other flexible, non-metal material. The first and second portions  10505 ,  10510  can comprise the same material or different materials. For example, the first portion  10505  may comprise a first material and the second portion  10510  may comprise a second material different than the first material. Additionally or alternatively, the first and second portions  10505 ,  10510  of the device  10500  may be formed of a single, unitarily-formed structure. As shown in  FIG. 105 , the second portions  10510  can protrude from and/or be disposed over the first portion  10505  such that the second portion  10510  faces in a general lingual direction when the device  10500  is disposed over the patient&#39;s teeth T. The first portion  10505  can include a plurality of regions, each of which corresponds to one or more of the patient&#39;s teeth T. In some embodiments, the device  10500  can be tailored to a particular patient&#39;s teeth T. For example, an occlusal-facing surface of each region of the first portion  10505  may correspond to a respective occlusal surface S of the tooth which the device  10500  is configured to be positioned over. In such embodiments, the device  10500  can fit securely over the patient&#39;s teeth T, e.g., to ensure the securing member  9600  received by the second portion  10510  are properly positioned, e.g., adjacent a lingual surface of patient&#39;s teeth T. 
     As explained elsewhere herein, once the device  10500  is positioned over the patient&#39;s teeth T, and/or the securing members  9600  are properly positioned, e.g., over a lingual surface of the patient&#39;s teeth T, the securing members  9600  may be adhered to respective ones of the patient&#39;s teeth T (e.g., by exposing the securing members  9600  to energy or ultraviolet (UV) light), after which the device  10500  may be removed from the patient&#39;s teeth T such that the securing members  9600  remain on the patient&#39;s teeth. Such a process used to position and/or adhere the securing members  9600  to a patient&#39;s teeth T is often referred to as “indirect bonding” or IDB. After adhering the securing members  9600  to the patient&#39;s teeth T, an orthodontic appliance (e.g., any of the appliances  100  described elsewhere herein) can be coupled to the securing members  9600  to reposition the patient&#39;s teeth to a desired arrangement (e.g., a final tooth arrangement). In such embodiments, the device  10500  itself is not used primarily to reshape or reposition the patient&#39;s teeth. 
       FIG. 106A  is an enlarged view of a portion of the device  10500  shown in  FIG. 105 . For illustrative purposes, the securing members  9600  have been removed in  FIG. 106A . As shown in  FIG. 106A , the device  10500 , or more particularly, the first portion  10505  of the device  10500 , can include one or more cavities  10515   a ,  10515   b ,  10515   c . As described elsewhere herein, each of the cavities  10515   a - c  can correspond to a respective tooth of the patient that the respective cavities  10515   a - c  are to be disposed over. The individual cavities  10515   a - c  together can form a single cavity that is configured to receive all of the patient&#39;s teeth along the upper or lower jaw. 
       FIG. 106B  is an enlarged isometric view of the second portion  10510  shown in  FIG. 105 . The first portion  10505  is not shown in  FIG. 106B  for illustrative purposes. As shown in  FIG. 106B , the securing member  9600  is coupled to and received by the second portion  10510 . As previously described, the securing member  9600  includes a base  9610 , and one or more coupling arms  9680  fixed to the base  9610  and spaced apart from one another. As explained elsewhere herein (e.g., with reference to  FIGS. 106C-106E ), the base  9610  is received within a cavity on one side of the second portion  10510 , and each of the coupling arms  9680  are disposed in respective channels of the second portion  10510  on an opposing side of the second portion  10510 . 
       FIGS. 106C and 106D  are isometric views of the second portion  10510  shown in  FIG. 106B  without the securing member  9600 .  FIG. 106C  shows a first side  10512   a  of the device  10500  and  FIG. 106D  shows a second, opposing side  10512   b  of the device  10500 . When the device  10500  is disposed over the patient&#39;s teeth, the first side  10512   a  of the device  10500  can generally face a lingual direction and the second side  10512   b  of the device  10500  can generally face a buccal (or facial) direction. Referring first to  FIG. 106C , the second portion  10510  can include a first region  10516  (e.g., an intermediate region or member) extending in a first direction, and a second region  10520  (e.g., a lateral region or member) extending in a second direction at an angle relative to the first direction. In some embodiments, the first region  10516  can be generally orthogonal to the second region  10520  or at an angle between about 60-120 degrees. The second portion  10510  may further comprise one or more third regions  10518   a ,  10518   b  (e.g., peripheral regions or members) peripheral to the first region  10516  and generally extending in the first direction. In use, such as when the device  10500  is disposed over a patient&#39;s teeth, the first region  10516  and the third regions  10518   a - b  can generally extend in the occlusal-gingival direction and the second region  10520  can generally extend in the mesial-distal direction. The first region  10516  and the second region  10520 , and in some embodiments the third regions  10518   a - b , can generally define one or more channels  10522   a ,  10522   b . As shown in  FIG. 106C , the first region  10516 , third region  10518   a , and part of the second region  10520  can define the first channel  10522   a , and the first region  10516 , third region  10518   b , and part of second region  10520  can define the second channel  10522   b . The second channel  10522   b  is spaced apart from the first channel  10522   a . Each of the first and second channels  10522   a - b  can be configured to receive a respective portion (e.g., a coupling arm  9680 ;  FIG. 106B ) of a securing member (e.g., the securing member  9600 ;  FIG. 106B ). 
     As further shown in  FIG. 106C , the second portion  10510  can comprise a bracket receiving portion  10530  disposed within each one of the channels  10522   a - b . The bracket receiving portion  10530  can include a recess  10532  configured to receive a portion of the securing member and/or secure the securing member to the second portion  10510  (and therein to the device  10500 ). In some embodiments, the bracket receiving portion  10530  may also include a curved surface  10534  adjacent the recess  10532  and closer to the entrance of the channel  10522   a - b . An outermost surface of the bracket receiving portion  10530  may be spaced apart from a base surface  10514   a  of the second portion  10510  by a distance D 2 , which may be less than a distance D 1  spanning between the base surface  10514   a  and an outermost surface of the first region  10516  or third regions  10518   a - b.    
     In operation, the bracket receiving portion  10530  can slidably receive the securing member  9600  ( FIG. 106B ) such that each of the coupling arms  9680  ( FIG. 106B ) of the securing member  9600  is received by a respective channel  10522   a - b  and engages the respective bracket receiving portion  10530 . As the coupling arms  9680  approach the respective recess  10532 , the curved surface  10534  displaces the respective coupling arm  9680  away from the base  9610  ( FIG. 106B ) of the securing member  9600  until the respective coupling arm  9680  reaches the respective recess  10532 , at which point the respective coupling arm  9680  snaps into the recess  10532  and/or becomes secured to the second portion  10510  (and therein to the device  10500 ) via the recess  10532 . When the respective coupling arms  9680  are snapped into and/or coupled to the recess  10532 , the coupling arms may be plasticly deformed relative to their default, at-rest position. 
     As previously described,  FIG. 106D  shows the second side  10512   b  of the second portion  10510  of the device  10500 . The second side  10512   b  is configured to receive the securing member  9600  ( FIG. 106B ) such that the base  9610  ( FIG. 106B ) is disposed proximate the base surface  10514   a . That is, the second portion  10510  is configured to receive the securing member  9600  such that the base  9610  is disposed on one side of a plane defined by the base surface  10514   a , and the coupling arms  9680  are disposed on another, opposing side of the plane. 
       FIG. 106E  is another view of the second side  10512   b  of the second portion  10510 , and illustrates the second portion  10510  integral with the first portion  10505  of the device  10500 .  FIG. 106E  also shows portions of the first side  10512   a  of the device  10500 , which includes the first region  10516 , third regions  10518   a - b , channels  10522   a - b , and bracket receiving portions  10530 . The second side  10512   b  of the second portion  10510  includes a cavity  10540  extending from the base surface  10514   a  and that is configured to receive the securing member  9600 . In some embodiments, the outermost surface of the cavity  10540  and/or second side  10512   b  may be spaced apart from the base surface  10514   a  by a distance D 3 , which may taper in a direction toward the entrance of the channels  10522   a - b . The distance D 3  may be equal to or less than a thickness of the securing member  9600 , or in some embodiments less than a thickness of the base  9610  of the securing member  9600 , such that a back surface of the securing member  9600  to be adhered to the patient&#39;s tooth can protrude from cavity  10540 , e.g., beyond the outermost surface of the second side  10512   b . The distance D 3  and/or the tapering of the outermost surface can thereby better ensure that when the securing member  9600  is received by the second portion  10510  and the device  10500  is positioned over the patient&#39;s teeth, the back surface of the securing member(s) can engage (e.g., directly engage) respective ones of the patient&#39;s teeth. 
       FIGS. 107A-107C  illustrate a method for attaching a securing member  9600  to a patient&#39;s teeth.  FIG. 107A  is an isometric view of the device  10500 , as described elsewhere herein. As shown in  FIG. 107A , the device  10500  includes the first portion  10505  and the second portion  10510 . Additionally, a plurality of securing members  9600  are positioned within and/or coupled to the second portion  10510 . As previously described, each of the securing members  9600  can be slidably received by a respective second portion  10510  such that the coupling arms  9680  of the securing members  9600  are disposed on a first side (e.g., a lingual-facing side) of the second portion  10510  and the base  9610  of the securing members  9600  is disposed on a second side (e.g., a buccal or labial-facing side) of the second portion  10510 . As described elsewhere herein, the securing members  9600  can include multiple coupling arms or portions (e.g., as shown in  FIG. 107A ) or a single coupling arm or portion (e.g., as shown in  FIG. 97 ). 
       FIG. 107B  is an isometric view of the device  10500  disposed over a patient&#39;s teeth or dentition T. For example, the first portion  10505  of the device  10500  is disposed over the patient&#39;s teeth T and the second portion  10510  of the device  10500  is generally disposed over or adjacent a lingual surface of the patient&#39;s teeth T. Moreover, the securing members  9600  disposed within the second portion  10510  are positioned or disposed over the lingual surface of the patient&#39;s teeth T such that a back surface of each of the securing members  9600  engages (e.g., directly engages) portions of respective ones of the patient&#39;s teeth T where the securing member is to be adhered. Accordingly, and as described elsewhere herein, when the device  10500  is disposed over the patient&#39;s teeth T, the second portion  10510  and/or the securing members  9600  are generally oriented in an occlusal-gingival direction. Once the device  10500  is disposed over the patient&#39;s teeth T, the securing members  9600  can be adhered (e.g., directly adhered) to the patient&#39;s teeth T, e.g., via an adhesive and/or a curable material disposed on the back surface of each of the securing members  9600 . The curable material can include a composite resin, ceramic, and/or other synthetic material. In some embodiments, the curable material can include dimethacrylate monomers, a filler material (e.g., silica), and/or a photoinitiator that may be activated by UV light (e.g., for bonding). In some embodiments, adhering the securing members  9600  to the patient&#39;s teeth T can comprise exposing the securing members  9600 , including the curable material disposed on the securing members  9600 , to an energy source (e.g., UV light). 
     After adhering the securing members  9600  to the patient&#39;s teeth T, the device  10500  can be removed from the patient&#39;s teeth T such that the securing members  9600  remain adhered to the patient&#39;s teeth T.  FIG. 107C  is an isometric view of the patient&#39;s teeth T with adhered securing members after the device  10500  has been removed. In some embodiments, removing the device  10500  such that the securing members  9600  remain adhered to the patient&#39;s teeth T can comprise decoupling the device  10500  from the securing members  9600  by moving or sliding the device  10500  in a general occlusive direction away from the patient&#39;s gingiva and/or the securing members  9600  adhered to the patient&#39;s teeth T. In some embodiments, prior to moving the device  10500  away from the securing members  9600 , individual securing members  9600  can be decoupled from respective second portions  10510  and/or the device  10500  by pushing down on an end portion (e.g., an end portion of the coupling arm closer to the patient&#39;s gingiva) of the coupling arm, thereby causing an opposing end of the coupling arm to uncouple from the second portion  10510  (e.g., to uncouple from the recess  10532  ( FIG. 106C ) of the second portion  10510 ). Once the device  10500  has been removed such that the securing members  9600  remain adhered to the patient&#39;s teeth T, an orthodontic appliance (as described elsewhere herein) can be coupled to the securing members  9600  to reposition the patient&#39;s teeth to a desirable position. 
       FIG. 108  is an isometric view of an example orthodontic device  10800 , configured in accordance with embodiments of the present technology. The device  10800  includes features generally similar to those of device  10500  described with reference to  FIGS. 105-107C . For example, the device  10800  includes a shell, cap, or shell-type aligner configured to be disposed over a patient&#39;s teeth and that includes the second portion  10510  configured to receive one or more securing members. Additionally, the device  1800  includes a first portion  10805  generally similar to the first portion  10505  previously described. However, as shown in  FIG. 108 , areas  10810  of the first portion  10805  between adjacent second portions  10510   a ,  10510   b  are removed. Stated differently, the areas  10810  between adjacent second portions  10510   a - b  of the device  10800  are substantially void of material such that the corresponding tooth or teeth adjacent the second portions  10510  are more exposed relative to teeth covered by the device  10500  and/or the first portion  10505  (as previously described). In such embodiments, the securing members, or more particularly the back surface of the securing members, are more exposed for the device  1800 , relative to the device  10500 . As such, for the device  10800 , when adhering the securing members to the respective teeth of the patient by exposing the securing members to UV light or an energy source, the practitioner can more easily access or expose the securing member to the UV light or energy and thereby ensure the securing member is properly adhered to the patient&#39;s tooth. 
       FIG. 109A  is an isometric view of an orthodontic device  10900 , configured in accordance with embodiments of the present technology. The device  10900  includes features generally similar to those of device  10500  described with reference to  FIGS. 105-107C . For example, the device  10900  includes a shell, cap, or shell-type aligner configured to be disposed over a patient&#39;s teeth and that includes the first portion  10505  (or first portion  10805 ) configured to receive a patient&#39;s teeth, as previously described. Additionally, the device  10900  includes a second portion  10910  generally similar to the second portion  10510  previously described. However, as shown in  FIG. 109A , the second portion  10910  omits certain portions of the second portion  10510 . As shown in  FIG. 109B , which is an enlarged view of a portion of the device  10900  shown in  FIG. 109A , the second portion  10910  of the device  10900  includes the first region  10516  (e.g., an intermediate region or member) extending in a first direction, and the second region  10520  (e.g., a lateral region or member) extending in a second direction at an angle (e.g., between 60-120 degrees) relative to the first direction. As previously described, in some embodiments the first region  10516  can be generally orthogonal to the second region  10520 . Relative to the second portion  10510  described with reference to  FIGS. 105-107C , the second portion  10910  of  FIG. 109B  omits the third regions  10518   a - b . As shown in  FIG. 109B , the second portion  10910  can also include the bracket receiving portion  10530  adjacent the first and second regions  10516 ,  10520 , e.g., proximate the intersection of the first and second regions  10516 ,  10520 . Advantageously, the second portion  10910  can enable more visibility of the securing member and/or the back surface of the securing member. As such, adhering the securing member to the patient&#39;s teeth, as described elsewhere herein, may be easier for the practitioner using the device  10900 , relative to the device  10500 . 
       FIGS. 110-113  are isometric views of example arms  130  of an orthodontic appliance  100 , configured in accordance with embodiments of the present technology. Referring first to  FIG. 110 , the arm  130  includes many features generally similar to those previously described with reference to  FIG. 95  and elsewhere herein. For example, as shown in  FIG. 110 , the arm  130  is coupled to the anchor  120 , and includes the biasing portion  150  extending from the anchor  120 , and an attachment portion  11040  extending from the biasing portion  150 . The arm  130 , or more particularly the attachment portion  11040 , can further include an opening or slot  11090 . The opening  11090  can extend through the attachment portion  11040  and/or a base region  9652  of the attachment portion  11040 . Additionally or alternatively, the opening  11090  can be positioned between second regions  11056  of the attachment portion  11040 . In some embodiments, the opening  11090  can be an elongate opening such that, when the appliance  100  is installed within a patient&#39;s mouth, the opening  11090  generally extends in the occlusal-gingival direction. As described elsewhere herein, the opening  11090  can be configured to receive a portion (e.g., an end portion) of an orthodontic tool to aid an operator in positioning the appliance  100  and/or individual arm  130  relative to a patient&#39;s teeth. 
       FIG. 111  is another example arm  130  similar to the arm  130  of  FIG. 110 , but further including a protrusion or member  11194 . As shown in  FIG. 111 , the protrusion  11194  is positioned on the arm  130  between the anchor  120  and the attachment portion  11040 . The protrusion  11194  can extend at an angle (e.g., about 90 degrees or between 60-120 degrees) from the portion of the arm  130  the protrusion is connected. As shown in  FIG. 111 , the protrusion  11194  can be an elongate, straight arm. In other embodiments, the protrusion  11194  can have a bend or curvature, and/or an “L” or “T” shape. When the appliance  100  is installed in a patient&#39;s mouth, the protrusion  11194  can generally extend in the mesial-direction direction. As described elsewhere herein, the protrusion  11194  can be utilized as a support such that an orthodontic tool (e.g., the same orthodontic tool configured to be received by the opening  11090 ) can position the appliance  100  and/or individual arm  130  via the protrusion  11194 . 
       FIG. 112  is another example arm  130  similar to the arm  130  of  FIG. 111 , but further including another protrusion  11294 . As shown in  FIG. 112 , each of the protrusions  11294  are positioned on opposing side of the arm  130  and are spaced apart from the attachment portion  11040  and/or biasing portion by the same distance. Each of (e.g., one or both of) the protrusions  11294  can extend at an angle (e.g., about 90 degrees or between 60-120 degrees) from the portion of the arm  130  the respective protrusions  11294  are connected. As shown in  FIG. 1112 , the protrusions  11294  can each be an elongate, straight arm. In other embodiments, each of the protrusions  11294  can have a bend or curvature, and/or an “L” or “T” shape. When the appliance  100  is installed in a patient&#39;s mouth, the protrusions  11294  can generally extend in the mesial-direction direction. As described elsewhere herein, the protrusions  11294  can be utilized as a support such that an orthodontic tool (e.g., the same orthodontic tool configured to be received by the opening  11090 ) can position the appliance  100  and/or individual arm  130  via the protrusions  11294 .  FIG. 113  is another example arm  130  similar to the arm  130  of  FIG. 112 , but without the opening  11090 . 
       FIGS. 114 and 115  are front views of orthodontic tools  11400 ,  11500  to be used with orthodontic appliances of the present technology. As shown in  FIG. 114 , the tool  11400  includes a handle  11410  and a distal region  11420  extending from the handle  11410 . The distal region  11420  can include an end portion  11430 . As shown in  FIG. 115 , the tool  11500  includes the handle  11410  and a distal region  11520  extending from the handle  11410 . The distal region  11520  can include a bend or swivel, e.g., that enables the practitioner to better manipulate, position, and/or control an orthodontic appliance. In some embodiments, the bend or swivel may be movable relative to another portion of the distal region  11520 . The distal region  11520  can also include an end portion  11530 . 
     As shown in the enlarged view of the end portion  11430 / 11530  in  FIG. 116 , the end portion  11430 / 11530  can include a notch  11602  formed by a recessed end surface  11650  of the device. The notch  11602  can extend through all or a portion of the thickness (or depth) of the device, and have a width bound by sidewalls  11645   a ,  11645   b . The end portion  11430 / 11530  can include an outermost width W 1  and a depth D 1 , and the notch  11602  can include a width W 2 . In some embodiments, the width W 1  can be approximately equal to a dimension of the opening  11090  of the arm  130  (e.g., as shown in  FIG. 117 ), thereby enabling the end portion  11430 / 11530  of the tool  11400  or  11500  to manipulate, position, and/or control the arm  130  of the appliance  100 . Additionally or alternatively, in some embodiments, a width W 2  can be approximately equal to the cross-sectional dimension of the portion of the arm  130  (such as arms  130  shown in  FIGS. 110-113 ) distal or proximal of where the protrusion or protrusions are positioned. Such a configuration enables the end portion  11430 / 11530  of the corresponding device to manipulate, position, and/or control the arm  130  of the appliance  100 . 
       FIGS. 117 and 118  are views of an orthodontic tool  11700  (e.g., the orthodontic tool  11400  or  11500 ) in use with orthodontic appliances of the present technology. As shown in  FIG. 117 , the end portion of the tool  11700  may be positioned at least partially within the opening of an arm  130  of an appliance  100 . As shown in  FIG. 118 , the end portion of the tool  11700  may be positioned against the protrusions of the corresponding attachment portion and/or arm, thereby enabling the practitioner to urge the arm  130  in a desired direction via the tool  11700 . 
     According to some embodiments, an attachment portion of the present technology can be configured for use with a securing member particularly suited for moving a patient&#39;s tooth in a preferred direction. For example,  FIG. 119A  depicts a securing member  11900  intended to move a patient&#39;s tooth in a mesial-distal direction to a greater extent an occlusal-gingival direction and/or buccal-lingual direction. In some embodiments, the preferred direction can be an occlusal-gingival direction, a buccal-lingual direction, and/or a direction oblique to the mesial-distal axis, the occlusal-gingival axis, and/or the buccal-lingual axis. An attachment portion of the present technology, such as attachment portion  11940  shown in  FIG. 119B , can be configured for use with securing member  11900 , as depicted in  FIG. 119C . Portions of the securing member  11900  and/or attachment portion  11940  may have a first stiffness that permits movement of the tooth in the mesial-distal direction, while other portions of the securing member  11900  and/or attachment portion  11940  have a second, greater stiffness that inhibits movement in the occlusal-gingival direction and/or buccal-lingual direction. 
       FIG. 119A  is an isometric view of a securing member  11900 , configured to move a tooth in a mesial-distal direction, as previously described. The securing member  11900  includes a base region  11905  having a first side  11907  and a second side  11909 , and first and second protrusions  11910   a ,  11910   a  (collectively “protrusions  11910 ”) disposed over and coupled to the first side  11907  of the base region  11905 . In some embodiments, the base region  11905  and the protrusions  11910  can comprise a unitary structure (e.g., a single component) that has a continuous surface. The second side  11909  can be configured to be bonded to a patient&#39;s tooth, e.g., via an adhesive, as described herein. The first protrusion  11910   a  may a first portion  11912   a  extending away from the first side  11907  of the base region  11905  (e.g., in a labial-facial direction), and a second portion  11914   a  extending laterally from the first portion  11912   a  toward a central area of the base region  11905  (e.g., in a mesial-distal direction) and/or toward the second protrusion  11910   b . The second protrusion  11910   b  includes a first portion  11912   b  extending away from the base region  11905  (e.g., in a labial-facial direction), and a second portion  11914   b  extending laterally from the first portion  11912   b  toward a central area of the base region  11905  (e.g., in a mesial-distal direction) and/or toward the first protrusion  11910   a . The first portion  11912   a , second portion  11914   a , and first side  11907   a  define a first opening or void  11916   a , and the first portion  11912   b , second portion  11914   b , and first side  11907  define a second opening or void  11916   b . The first and second openings  11916   a ,  11916   b  (collectively “openings  11916 ”), are configured to receive and secure portions of an attachment portion of an orthodontic appliance, as explained herein. 
       FIG. 119B  is an isometric view of an attachment portion  11940  configured to be coupled to a securing member such as securing member  11900  shown in  FIG. 119A . In  FIG. 119B , the attachment portion  11940  is depicted coupled to a serpentine biasing portion  11950  that, together with the attachment portion  11940 , comprises an arm  11930  that extends from anchor  11920 . It will be appreciated that the attachment portion  11940  may be used with any of the arm configurations described herein, and/or can be coupled to any of the biasing portions and/or connectors described herein. 
     As shown in  FIG. 119B , the attachment portion  11940  can comprise first and second extensions  11970   a ,  11970   b  extending distally from a common point and generally away from the biasing portion  11950  and/or anchor  11920 . In some embodiments, the anchor  11920 , the biasing portion  11950 , and the attachment portion  11940  can comprise a unitary structure that has a continuous surface. As shown in  FIG. 119B , the first extension  11970   a  may comprise an elongate member extending along a first direction, a proximal arm  11972   a , a distal arm  11974   a  spaced apart from the proximal arm  11972   a , and an opening  11976   a  between the proximal and distal arms  11972   a ,  1974   a . The proximal and distal arms  11972   a ,  11974   a  can extend along a second direction that is angled and/or orthogonal to the first direction. The second extension  11970   b  can comprise an elongate member extending in a third direction, as well as a proximal arm  11972   b , a distal arm  11974   b  spaced apart from the proximal arm  11972   b , and an opening  11976   b  between the proximal and distal arms  11972   b ,  11974   b . The proximal and distal arms  11972   b ,  11974   b  can extend along a fourth direction that is angled and/or orthogonal to the third direction. In some embodiments, the second and fourth directions are generally mesial-distal directions. In some embodiments, the first extension  11970   a  may generally be a mirrored reflection of the second extension  11970   b  about an axis A 1 . In some embodiments, at least a portion of the first and third directions can be generally parallel to axis A 1 . As shown in  FIG. 119B , a portion of the first and third direction that the first and second extensions  11970   a ,  11970   b  extend along can be disposed at an angle to axis A 1  such that the first and second extensions  11970   a ,  11970   b  are biased in generally opposing directions from one another. For example, the first extension  11970   a  may be biased in the mesial direction and the second extension  11970   b  may be biased in the distal direction. Biasing of the first and/or second extensions  11970   a ,  11970   b  can facilitate coupling of the attachment portion  11940  to the securing member  11900 , as described below. 
       FIG. 119C  is an isometric view of the securing member  11900  and the attachment portion  11940  configured to move a tooth in a preferred mesial-distal direction. As shown in  FIG. 119C , the attachment portion  11940  can be configured to be coupled to the securing member  11900 . The opening  11976   a  ( FIG. 119B ) of the first extension  11970   a  of the attachment portion  11940  can be configured to be received by the opening  11916   a  ( FIG. 119A ) of the first protrusion  11910   a  of the securing member  11900 , such that the proximal and distal arms  11972   a ,  11974   a  are configured to be positioned in apposition with and on opposing sides of the first protrusion  11910   a . The opening  11976   b  ( FIG. 10B ) of the second extension  11970   b  of the attachment portion  11940  may be configured to be received by the opening  11916   b  ( FIG. 119A ) of the second protrusion  11910   b  of the securing member  11900 , such that the proximal and distal arms  11972   b ,  11974   b  are configured to be positioned in apposition with and on opposing sides of the second protrusion  11910   b.    
     In some embodiments, a lateral distance between first and second protrusions  11910   a ,  11910   b  of the securing member  11900  can be less than a lateral distance between openings  11976   a ,  11976   b  of the attachment portion  11940  such that first and second extensions  11970   a ,  11970   b  of the attachment portion  11940  are configured to be compressed when the attachment portion  11940  is coupled to the securing member  11900 . First and second extensions  11970   a ,  11970   b  can thus apply mesial-distal directed forces to the first and second protrusions  11910   a ,  11910   b  for secure coupling of the attachment portion  11940  to the securing member  11900  and to prevent translation of the attachment portion  11940  relative to the securing member  11900  along or about the mesial distal, occlusal-gingival, and/or lingual-facial axes. Engagement of the first and second extensions  11970   a ,  11970   b  with the first and second protrusions  11910   a ,  11910   b  may also serve to transfer force from an appliance to a patient&#39;s tooth. 
       FIG. 120A  depicts another embodiment of a securing member  12000  configured to move a tooth in a preferred mesial-distal direction. The securing member  12000  can include features generally similar to those of the securing member  11900  previously described. For example, the securing member  12000  may include a base region  12005 , a first protrusion  12010   a , a second protrusion  12010   b , a third protrusion  12010   c , and/or a fourth protrusion  12010   d  (collectively “protrusions  12010 ”). As shown in  FIG. 120A , the third protrusion  12010   c  may be spaced apart from the first protrusion  12010   a  to define an opening  12015   a  and/or the fourth protrusion  12010   d  may be spaced apart from the second protrusion  12010   b  to define an opening  12015   b  (collectively “openings  12015 ”). In some embodiments, the openings  12015  can be configured to receive a portion of an attachment region. For example, the opening  12015   a  may be configured to receive the distal arm  11974   a  of attachment portion  11940 . The protrusions  12010  may be generally similar to the first and second protrusions  11910   a ,  11910   b  previously described in reference to  FIG. 119A . 
     In some embodiments, at least one of the protrusions  12010  can include a first portion extending away from the base region  12005  (e.g., in a labial-facial direction) and a second portion extending laterally from the first portion toward a central area of the base region  12005  (e.g., in a mesial-distal direction) to define an opening  12035  between the second portion and the base region  12005 . The opening  12035  may be configured to receive a portion of an of attachment portion such as attachment region  11940 . 
     According to some embodiments, for example as depicted in  FIG. 120B , the attachment portion  11940  shown in  FIG. 119B  may be configured to be coupled to the securing member  12000 . In some cases, securing member  12000  can be configured to inhibit translation of the attachment portion as compared to securing member  11900  to a greater extent than other securing members (e.g., securing member  11900 ). The proximal arm  11972   a  of the first extension  11970   a  of the attachment portion  11940  may be configured to be positioned within the opening  12035  ( FIG. 120A ) of the securing member  12000 . The distal region  11974   a  of the first extension  11970   a  may be configured to be positioned distally to the first protrusion  12010   a  of the securing member  12000 . Similarly, the proximal region  11972   b  of the second extension  11970   b  of the attachment portion  11940  may be configured to be disposed within the opening  12025  ( FIG. 120A ) securing member  12000  and/or the distal region  11974   b  of the second extension  11970   b  may be configured to be positioned distal to the second protrusion  12010   b.    
     In some embodiments, the proximal regions  11972   a ,  11972   b  and/or the distal regions  11974   a ,  11974   b  may be configured to contact adjacent protrusions  12010  of the securing member  12000  when the attachment portion  11940  is coupled to the securing member  12000 . According to some embodiments, a degree of coupling between the attachment portion  11940  and the securing member  12000  can be based, at least in part, on biasing of the first and second extensions  11970   a ,  11970   b  and/or forces imparted on the proximal regions  11972   a ,  11972   b  and/or distal regions  11974   a ,  11974   b  by the protrusions  12010 . The attachment portion  11940  may be configured to be secured to the corresponding securing member  12000  by compressing the first and second extensions  11970   a ,  11970   b , positioning the proximal regions  11972   a ,  11972   b  and/or distal regions  11974   a ,  11974   b  adjacent the protrusions  12010  as previously described, and removing the compressive force from the first and second extensions  11970   a ,  11970   b . According to some embodiments, the third and fourth protrusions  12010   c ,  12010   d  of the securing member  12000  may limit translation of the attachment portion  11940  relative to the securing member  12000  along or about the mesial-distal, occlusal-gingival, and/or lingual-facial axes. 
       FIGS. 121A-C  depict a securing member and an attachment portion in accordance with the present technology. As shown in  FIG. 121A , a securing member  12100  can have a base region  12105  having a generally ovular shape, a first side  12107 , and a second side  12109 . Compared to the securing member  11900  described with reference to  FIG. 119A , the ovular base region  12105  of the securing member  12100  can contact a greater area of the patient&#39;s tooth to facilitate force transfer from an appliance to the tooth. The securing member  12100  can include first and second protrusions  12110   a ,  12110   b  (collectively “protrusions  12110 ”) extending from base region  12105 . In some embodiments, the base region  12105 , first protrusion  12110 , and second protrusion  12120  can comprise a monolithic structure and/or separate components joined by adhesive, bonding, welding, or another suitable joining method. The second side  12109  of the base region  12105  may be configured to be bonded to a patient&#39;s tooth, as explained herein. 
     In some embodiments, the first protrusion  12110   a  can include a first portion  12112   a  extending away from the base region  12105  (e.g., in a labial-facial direction) and a second portion  12114   a  extending laterally from the first portion  12112   a  toward a central area of the base region  12105  (e.g., in a mesial-distal direction) to define an opening  12035  between the second portion  12114   a  and the base region  12005 . Similarly, the second protrusion  12110   b  can include a first portion  12112   b  extending away from the base region  12105  (e.g., in a labial-facial direction) and a second portion  12114   b  extending laterally from the first portion  12112   b  toward a central area of the base region  12105  (e.g., in a mesial-distal direction) to define an opening  12035  between the second portion  12114   b  and the base region  12005 . The openings  12035  may be configured to receive a portion of an attachment region (e.g., first extension  11970   a , second extension  11970   b ). 
       FIG. 121B  is an isometric view of an attachment portion  12140 , configured in accordance with embodiments of the present technology. In  FIG. 121B , the attachment portion  12140  is depicted coupled to a serpentine biasing portion  12150  that, together with the attachment portion  12140 , comprises an arm  12130  that extends from an anchor  12120 . It will be appreciated that the attachment portion  12140  may be used with any of the arm configurations described herein, and/or can be coupled to any of the biasing portions and/or connectors described herein. 
     In some embodiments, the attachment portion can be configured for increased coupling security and/or efficient force transfer to a tooth. As shown in  FIG. 121B , the attachment portion  12140  can comprise a distal region  12165  connected to first and second proximal regions  12170   a ,  12170   b  by intermediate portions  12174   a ,  12174   b . In some embodiments, for example as shown in  FIG. 121B , a proximal end of the first proximal region  12170   a  can be attached to the biasing portion  12150 . First and second arms  12172   a ,  12172   b  can extend laterally from corresponding first and second proximal regions  12170   a ,  12170   b . In some embodiments, first and second arms  12172   a ,  12172   b  extend away from a midline of the attachment portion  12140 . An opening (e.g., first opening  12176   a , second opening  12176   b ) can be defined by a distance separating an arm and a corresponding intermediate portion. According to some embodiments, openings  12176   a ,  12176   b  can be configured to receive a protrusion of a securing member. As shown in  FIG. 121B , the distal region  12165  may comprise a semicircular shape that can generally correspond to a shape of a base region of a securing member (e.g., base region  12107  of securing member  12100 ). Based on this geometric relationship, the attachment portion  12140  can contact a greater area of securing member  12100  for enhanced coupling and to limit translation of the attachment portion  12140  relative to the securing member  12100 . According to some embodiments, first and second proximal regions  12170   a ,  12170   b  of the attachment portion  12140  can be biased such that a distance between distal ends of the proximal regions  12170   a ,  12170   b  is less than a distance between proximal ends of the proximal regions  12170   a ,  12170   b . Biasing of the first and second proximal regions  12170   a ,  12170   b  can facilitate coupling of the attachment portion  12140  to the securing member  12100 , as described below. 
     As shown in  FIG. 121C , the attachment portion  12140  can be configured to be coupled to the securing member  12100 . Each opening  12176   a ,  12176   b  of the attachment portion  12140  can be configured to receive a corresponding protrusion  12110  of the securing member  12100 . Biasing of the first and second proximal regions  12170   a ,  12170   b  can result the first and second proximal regions  12170   a ,  12170   b  being configured to apply a laterally-outward force to the protrusions  12110  to facilitate coupling of the attachment portion  12140  to the securing member  12100 . 
     According to some aspects of the present technology, protrusions of a securing member can be configured to limit a specific directional translation and/or rotation of an attachment portion relative to the securing member. For example,  FIG. 122  depicts a securing member  12200  comprising first and second protrusions  12210   a ,  12210   b , as previously described. The securing member  12200  can further comprise a third protrusion  12210   c  positioned at a distal end of a base region  12205  of the securing member  12200 . The third protrusion  12210   c  can extend from a first end  12212  in a direction generally distal and away from the base region  12205  (e.g., in a labial-facial direction) toward an apex region  12214 . The third protrusion  12210   c  can extend from the apex region  12214  proximally and away from the base region toward a second end  12216 . An opening  12236  can be defined between the second end  12216  of the third protrusion  12210   c  and the base region  12205  of the securing member. The opening  12236  can be configured to receive a region of an attachment portion, for example, the distal region  12165  of the attachment portion  12140  (see  FIG. 121B ), and thereby secure the attachment portion  12140  to the securing member  12200 . Consequently, the third protrusion  12230 , or more generally the securing member  12200 , can be configured to prevent translation and/or rotation of the attachment portion relative to the securing member  12200 . In particular, the third protrusion  12230  can be configured to limit translation of the attachment portion  12140  along the occlusal-gingival and/or lingual-facial axes and/or to limit rotation of the attachment portion about the mesial-distal and/or lingual-facial axes. 
     In some embodiments, for example as shown in  FIG. 123 , a securing member  12300  can comprise a protrusion with a larger area to enhance coupling of an attachment portion to the securing member  12300 . The securing member  12300  can include features generally similar to those of the securing member  12100  previously described. As shown in  FIG. 123 , in addition to the first and second protrusions  12310   a ,  12310   b , the securing member  12300  may include a third protrusion  12310   c  (e.g., a plate) disposed at an upper portion of the base region  12305 . The third protrusion  12310   c  can generally extend away from the base region  12305  in a direction similar to the first and second protrusions  12310   a ,  12310   b , such that the third protrusion  12310   c  extends in a lateral direction across all or a portion of the base region  12305 . The third protrusion  12310   c  can define a surface facing toward the first and second protrusions  12310   a ,  12310   b , with the first, second, and third projections  12310   a ,  12310   b ,  12310   c  defining an opening  12336  therebetween. The opening  12336  can be configured to receive a region (e.g., the distal regions  11974   a ,  11974   b  ( FIG. 119B )) of an attachment portion (e.g., the attachment portion  11940 ), and thereby better secure that region to the securing member  12300 . In doing so, the third protrusion  12310   c , or more generally the securing member  12300 , can further inhibit movement and/or rotation of an attachment portion relative to the securing member  12300 . 
     According to some embodiments, a securing member and/or an attachment portion can be configured to urge a patient&#39;s tooth in at least an occlusal-gingival direction. For example, the securing member  12400  depicted in  FIG. 124A  can have a length L to width W ratio greater than that of securing members of previously described embodiments. The securing member  12400  may comprise a base region  12405  and first and second protrusions  12410   a ,  12410   b  (collectively “protrusions  12410 ”) attached to and extending along a lingual-facial axis away from the base region  12405 . Each protrusion can define an opening  12435  configured to receive a region of an attachment portion as described herein. As shown in  FIG. 124A , openings  12435  can extend along a mesial-distal axis through the protrusions  12410 , in contrast to the openings that extend along an occlusal-gingival axis in  FIGS. 119A, 120A, 121A, 122 and 123 . 
       FIG. 124B  shows an example of an attachment portion  12440  configured for use with a securing member, such as the securing member  12400  shown in  FIG. 124A . In  FIG. 124B , the attachment portion  12440  is depicted coupled to a serpentine biasing portion  12450  that, together with the attachment portion  12440 , comprises an arm  12430  that extends from anchor  12420 . It will be appreciated that the attachment portion  12440  may be used with any of the arm configurations described herein, and/or can be coupled to or include any of the biasing portions and/or connectors described herein. 
     The attachment portion  12440  may comprise first and/or second extensions  12460 ,  12470  extending from a common proximal point along directions generally away from the biasing portion  12450  and/or anchor  12420 . The first extension  12460  may be an elongate member comprising a distal region  12462 , a first distal arm  12464   a  and a second distal arm  12464   b  (collectively “distal arms  12464 ”). The first and second distal arms  12464   a ,  12464   b  can extend distally from the distal region  12462  and/or can be spaced apart to define an opening  12466 . The first extension  12460  can also include a distal biasing region  12465  configured to bias the distal arms  12464  in an occlusal and/or gingival direction and/or to urge the distal arms  12464  in the occlusal-gingival direction. The second extension can include a lateral regions  12474   a ,  12474   b . In some embodiments the first and second extensions  12460 ,  12470  are moveable toward and/or away from one another, e.g., in the occlusal-gingival direction, and may be biased in generally opposing directions from one another. For example, the first extension  12460  may be biased in the gingival direction and the second extension  12470  may be biased in the occlusal direction 
     As shown in  FIG. 124C , the attachment portion  12440  can be configured to be detachably secured to the securing member  12400 . The opening  12466  ( FIG. 124B ) of the first extension  12460  of the attachment portion  12440  may be configured to receive the opening  12435  ( FIG. 124A ) of the protrusion  12410   a  of the securing member  12400 , such that the distal arms  12464  are configured to be positioned in apposition to and on opposing sides of the first protrusion  12410   a . The opening  12476  ( FIG. 124B ) of the second extension  12470  of the attachment portion  12440  may be configured to receive the opening  12435  ( FIG. 124A ) of the second protrusion  12410   b  of the securing member  12400 , such that the lateral regions  12474   a ,  12474   b  are configured to be positioned in apposition to and on opposing sides of the second protrusion  12410   b.    
     In operation, the attachment portion  12440  may be configured to be secured to the securing member  12400 , which may be bonded to one of the patient&#39;s teeth by moving the first extension  12460  toward the second extension  12470  (or vice versa), and then releasing the first extension  12460  (or the second extension  12470 ) such that it is secured within the opening  12435  ( FIG. 124A ) of the first protrusion  12410   a  (or within the opening  12435  of the second protrusion  12410   b ). In doing so, the engagement of the first and second extensions  12460 ,  12470  with the respective first and second protrusions  12410   a ,  12410   b  help ensure the desired force is applied to the patient&#39;s tooth via the securing member  12400 . Additionally or alternatively, the engagement of the first and second extensions  12460 ,  12470  with the respective first and second protrusions  12410   a ,  12410   b  can prevent translation of the attachment portion  12440  relative to the securing member  12440  along or about the mesiodistal, occlusogingival, and/or lingual-facial axes. 
     Additionally, some embodiments of embodiments of the securing member  12400  and/or attachment portion  12440  may be particularly suited for moving the patient&#39;s teeth in a specific direction. For example, in some embodiments the securing member  12400  and/or attachment portion  12440  may be configured to more easily move a patient&#39;s teeth in the gingival direction relative to the occlusal direction, mesial-distal direction and/or buccal-lingual direction. That is, portions of the securing member  12400  and/or attachment portion  12440  may have a first stiffness that enable teeth movement in the gingival direction, while other portions of the securing member  12400  and/or attachment portion  12440  have a second, greater stiffness that inhibit movement in other directions, such as the occlusal direction, and/or buccal-lingual direction. 
       FIG. 125A  is an isometric view of a securing member  12500  configured in accordance with embodiments of the present technology. The securing member  12500 , for example, may be a SPEED Appliance (SPEED System Orthodontics, Ontario, Canada). The securing member  12500  may include a body region  12505  having a back surface  12510  configured to be attached to a patient&#39;s tooth, a recess  12512  configured to receive a portion of an attachment portion, a lip portion  12514 , and/or a clip portion  12520  movable relative to and extending outwardly from the body region  12505 . The clip portion  12520  can include a clip and a biasing element (e.g., a spring). The biasing element can be configured to bias the clip to remain in the closed position (as shown in  FIG. 125A ). When force is applied (e.g., by an operator) the biasing element can be configured to enable the clip to move from the closed position away from the body region  12505 , slot  12512 , and/or lip portion  12514  toward an open position (e.g., in an occlusal-gingival direction). The clip portion  12520  in the open position can be configured to enable a portion of an attachment portion to be inserted into the slot  12512 . That is, the slot  12512  becomes exposed when the clip portion  12520  is in the open position, thereby allowing a portion of the attachment portion to be inserted thereto. In the closed position, the lip portion  12514  can help ensure the clip portion  12520  remains in the closed position and/or prevent the attachment portion from being inadvertently removed from the slot  12512 . 
       FIG. 125B  is an isometric view of an attachment portion  12540 , configured in accordance with embodiments of the present technology. In  FIG. 125 , the attachment portion  12540  is depicted coupled to a serpentine biasing portion  12550  that, together with the attachment portion  12540 , comprises an arm  12530  that extends from anchor  9520 . It will be appreciated that the attachment portion  12540  may be used with any of the arm configurations described herein, and/or can be coupled to any of the biasing portions and/or connectors described herein. The attachment portion  12540  can comprise a base region  12570  configured to be received by a securing member. According to some embodiments, for example as shown in  FIG. 125B , the base region  12570  can have a generally rectangular shape with an opening  12580  therethrough. A rectangular shape may facilitate prevention of rotation of the attachment portion  12540  relative to a securing member. In some embodiments, the attachment portion  12540  may have another suitable shape (e.g., circular, polygonal, triangular, etc.). 
       FIG. 125C  is an isometric view of the securing member  12500  shown in  FIG. 125A  and the attachment portion  12540  shown in  FIG. 125B . As shown in  FIG. 125C , the attachment portion  12540  may be secured to the securing member  12500 . Specifically, the lip portion  12514  of the securing member  12500  can be configured to extend through the opening  12580  of the attachment portion  12540 , and a first portion  12572  of the base region  12570  can be configured to be disposed within the slot  12512  of the securing member  12500 .  FIG. 125C  depicts the clip portion  12520  in the closed position and disposed over the first portion  12572  of the base region  12570 , thereby securing the first portion  12572  within the slot  12512  and more generally the attachment portion  12540  to the securing member  12500 . 
     According to some embodiments, a securing member such as securing member  12600  shown in  FIG. 126A  may be formed from a curable material. The securing member  12600  can include one or more distinct portions  12610   a - d  that have been cured to form a cured structure. The distinct portions  12610   a - d  may be spaced apart from one another to define an indentation  12680 . Although the securing member  12600  shown in  FIG. 126A  has four portions  12610   a - d , in some embodiments, the securing member  12600  may have more than four portions or less than four portions. As shown in  FIG. 126A , the indentation  12680  may form a generally cross or “+” shape. A shape of the indentation  12680  may be based at least in part on a shape of an attachment portion configured to be coupled to the securing member  12600 . For example, the cross-shaped indentation  12680  depicted in  FIG. 126A  may be configured to receive a cross-shaped attachment portion. 
     The securing member  12600  may be formed of a curable material such that the securing member  12600  may be configured to be bonded directly to a patient&#39;s tooth, e.g., without the need for additional materials or bonding agents. The curable material can be generally moldable prior to being cured, and can include a composite resin, ceramic, and/or other synthetic material. In some embodiments, the curable material can include dimethacrylate monomers, a filler material (e.g., silica), and/or a photoinitiator that may be activated by UV light for bonding. The curable material can be bonded directly to the patient&#39;s tooth. In some embodiments, the curable material is the only component of the securing member  12600 . As such, embodiments of the securing member  12600  can minimize the cost and difficulties associated with manufacturing multiple components together and/or coupling multiple components of a traditional securing member to a patient&#39;s tooth. 
       FIG. 126B  is a front view of an attachment portion  12640  of an orthodontic appliance and the securing member  12600 , configured in accordance with embodiments of the present technology. The attachment portion  12640  can correspond to any one of the attachment portions described herein. As shown in  FIG. 126B , the attachment portion  12640  may have a shape complementary to a shape of the indentation  12680  ( FIG. 126A ) formed by the portions  12610   a - d . The complementary nature of the shape of the attachment portion  12640  to the indentation  12680  can help inhibit movement of the attachment portion  12640  relative to the indentation  12680  along and/or about the mesial-distal, occlusal-gingival, and/or lingual-facial axes. 
     According to some embodiments, the securing member  12600  may be manufactured and coupled to a patient&#39;s tooth simultaneously. In some embodiments, the securing member  12600  is manufactured and then coupled to a patient&#39;s tooth. Manufacturing the securing member  12600  can include providing a support (e.g., a tray) having indentations complementary to portions  12610   a - d  shown in  FIG. 126A . The indentations of the support may be filled with the curable or moldable material, and the support may be subsequently positioned adjacent the patient&#39;s tooth. Energy (e.g., UV light) is applied to the support and curable material to form a cured structure. In some embodiments, the applied energy may also cause the curable material to bond to the patient&#39;s tooth. In some embodiments, an adhesive that does not require UV light to cure may be used. After curing, the support can be removed from the patient&#39;s mouth while the cured material (i.e., the securing member  12600 ) remains attached to the patient&#39;s tooth. Once the securing member  12600  is secured to the patient&#39;s tooth, an appliance or arm of an appliance can be coupled to the securing member  12600  by positioning an attachment portion of the arm within the indentation defined by the securing member. The attachment portion can be secured by disposing an adhesive, composite resin, or other synthetic material over the attachment portion within the indentation. The adhesive, composite resin, or synthetic material used to secure the attachment portion to the securing member  12600  may be cured via UV light. In some embodiments, the attachment portion is secured to the securing member  12600  without UV light. 
       FIG. 127A  is an isometric view of a securing member  12700  formed from a curable material, configured in accordance with embodiments of the present technology. The securing member  12700  and manufacturing methods thereof may be generally similar to those of the securing member  12600  previously described with reference to  FIGS. 126A and 126B . As shown in  FIG. 127A , the securing member  12700  may include distinct portions  12710   a - c  that have been cured to form a cured structure and are spaced apart from one another to define an indentation  12780 . As shown in  FIG. 127A , the indentation  12780  generally forms a heart shape with multiple extensions therefrom and is configured to receive an attachment portion of an orthodontic appliance or arm having that or a similar shape. In other embodiments, the indentation  12780  can define other shapes (e.g., a circle, triangle, polygon, cloud, apple, etc.) as needed for a particular application or desired by a patient. 
       FIG. 127B  is an isometric view of an attachment portion  12740  configured to mate with securing member  12700 . The attachment portion  12740  may have a shape complementary to the shape of the indentation  12780  ( FIG. 127A ) formed by the portions  12710   a - c . The complementary nature of the shape of the attachment portion  12740  to the indentation  12780  can help inhibit movement and/or rotation of the attachment portion  12740  relative to the indentation  12780  along or about the mesial-distal, occlusal-gingival, and/or lingual-facial axes 
     In some cases, it may be beneficial to configure an attachment portion with openings configured to receive and/or retain a moldable and/or curable material to adhere the attachment portion to the patient&#39;s tooth.  FIG. 128A  depicts an attachment portion  12840  comprising a base region  12855  having a generally planar surface and including one or more openings  12880   a - c  (collectively “openings  12880 ”) extending through the base region  12855 . According to some embodiments, for example as shown in  FIG. 128B , the attachment portion  12840  may be configured to be coupled to a pad  12180 . The pad  12810  may be configured to be bonded to a patient&#39;s tooth. In some embodiments, the pad  12810  may be formed of a mesh material. The pad  12810  can be secured to the attachment portion  12840  via coupling elements (not shown) extending through the openings  12880  and at least partially through the pad  12810 . As shown in  FIG. 128B , the pad  12810  may have a surface area greater than a surface area of the base region  12855  of the attachment portion  12840 . As such, when coupled to the attachment portion  12840 , the pad  12810  can be configured to increase the bonding surface between the patient&#39;s tooth and the attachment portion  12840 , thereby forming a stronger bond therebetween. 
     Although  FIGS. 128A and 128B  depict three of the openings  12880  in the base region  12855  of the attachment portion  12840 , in some embodiments, the attachment portion  12840  may include more than three or fewer than three openings  12880 . For example,  FIG. 129  depicts an attachment portion  12940  comprising a base region  12955  having eighteen openings  12980  extending through the base region  12955 . 
     In some embodiments, the attachment portion  12940  can be bonded directly to a patient&#39;s tooth and, in such embodiments, the openings  12980  may be configured to receive and retain a moldable and/or curable material that adheres the attachment portion  12940  to the patient&#39;s tooth. The moldable and/or curable material may be any of the materials described herein (e.g., with reference to  FIG. 126A ). In some embodiments, the moldable and/or curable material may be cured (e.g., via UV light) once disposed within the openings  12980 . Advantageously, embodiments of the attachment portion  12940  can be secured to a patient&#39;s tooth without the need for a separate securing member. 
     According to some aspects of the present technology, a securing member can be configured to have a recess of varying depth throughout the recess, for example as shown in  FIGS. 130A and 130B .  FIGS. 130A and 130B  are front and back isometric views, respectively, of a securing member  13000 , configured in accordance with embodiments of the present technology. Referring first to  FIG. 130A , the securing member  13000  can include one or more distinct portions  13010   a - c  spaced apart from one another. The distinct portions  13010   a - c  may together define a recess  13080 . The recess  13080  can have a first area including a base surface  13025  of the securing member  13000  configured to receive an attachment portion. Second distinct portions  13015   a - c  can have a second area spaced apart along a lingual-facial axis from the base surface  13025 . The first area can have a shape that generally resembles or compliments that of the attachment portion to be disposed therein. The second area can include a curable material (as previously described) or be configured to receive a curable material after the attachment portion has been disposed within the first area. Such a curable material can secure, or further secure, the attachment portion to the securing member  13000 . In some embodiments, the second area may be roughened to increase its surface area and therein improve the bonding strength between the second area and curable material disposed thereon. 
     Referring to  FIG. 130B , the securing member  13000  can have a back side  13005  configured to be bonded to a patient&#39;s tooth. The back side  13005  can include a curable material or be configured to receive a curable material, as previously described, for coupling the securing member  13000  to a patient&#39;s tooth. In some embodiments, the back side  13005  may be roughened to increase its surface area and therein improve the bonding strength between the back side  13005  and curable material disposed thereon. 
       FIG. 130C  is an isometric view of an attachment portion  13040  and the securing member  13000  shown in  FIGS. 130A and 130B , configured in accordance with embodiments of the present technology. In  FIG. 130C , the attachment portion  13040  is depicted coupled to a serpentine biasing portion  13050  that, together with the attachment portion  13040 , comprises an arm  13030  that extends from anchor  13020 . It will be appreciated that the attachment portion  13040  may be used with any of the arm configurations described herein, and/or can be coupled to any of the biasing portions and/or connectors described herein. 
     As shown in  FIG. 130C , the attachment portion  13040  may have a shape generally similar to the shape of the first area of the recess  13080  ( FIG. 130A ). As shown in  FIG. 130C , the attachment portion  13040  may include portions  13070  extending laterally away from the securing member  13000 . When the appliance  100  is disposed or installed within a patient&#39;s mouth and the secured to the securing member  13000 , the portions  13070  can extend generally in a mesial-distal direction. In some embodiments, the portion  13070  may be configured to be coupled to adjacent ones of the patient&#39;s teeth and/or to adjacent arms  13030  of the appliance. The complementary nature of the attachment portion  13040  and the securing member  13000  can help further inhibit movement and/or rotation of the attachment portion  13040  relative to the securing member  13000 . 
       FIG. 131  shows a retainer  13100  configured in accordance with embodiments of the present technology. In some embodiments, for example as shown in  FIG. 131 , the retainer  13100  may comprise an elongated member having a series of alternating curved segments  13102  and straight (or mesiodistal) segments  13104 . The retainer  13100  may be configured to be bonded directly to the patient&#39;s teeth (i.e., without the use of a bracket) in such a way that the patient cannot remove the retainer. The retainer may be configured to be positioned such that the curved, U-shaped portions are aligned with the mesial and distal surfaces of adjacent teeth, and the more linear segments extend in a generally mesiodistal direction along the surface of the tooth between curved segments  1302 . Positioning the curved segments between the teeth provides the advantage of allowing the patients to floss. In some embodiments, the curved segments are flexible while the more linear segments are rigid. Other configurations are possible. 
     Any of the appliance and connector configurations disclosed herein may be permanently attached to the patient&#39;s teeth (i.e., such that the patient cannot remove the appliance).  FIG. 132  depicts a jig that may be utilized to hold the retainer at the correct position at the surface of the teeth while the retainer is bonded to the teeth.  FIGS. 132-134  show different IDBs that may be used for making and positioning the retainer. 
     Systems and processes according to any of the examples described herein or other examples may include a comfort cover or retainer device that is configured to be worn by a patient, while the patient has the appliance in the mouth. 
     The cover or retainer may be a comfort cover that covers the brackets and the appliance during treatment, and has a smooth outer surface to provide additional comfort to the user. In some examples, the comfort cover or retainer is configured to fit over and cover an appliance and brackets as described herein. In other examples, the comfort cover or retainer may be configured to cover other types of dental appliances, traditional braces, or the like. 
     In particular examples, the comfort cover or retainer may include a retainer body having a shape to fit over and cover some or all of the teeth in a patient&#39;s jaw (upper jaw or lower jaw). In particular examples, the retainer body is shaped to fit over at least some of the patient&#39;s teeth and provide a sufficiently tight or snug fit on the patient&#39;s teeth, so as to retain the retainer body on the patient&#39;s teeth, yet allow the patient to selectively remove (slide off) the retainer from the teeth. 
     In some examples, the comfort cover or retainer may be configured similar to (and of similar materials as) the aligner body described above, but is configured to cover the appliance and bracket during treatment, while the appliance is secured to the brackets. In other examples, the comfort cover or retainer may be made of other suitable materials or shapes. The retainer body may be formed by any suitable process as described herein and may be formed from an impression taken of the patient&#39;s teeth. In particular examples, the retainer body is shaped to provide a sufficiently tight fit to be retained on a patient&#39;s teeth (over an appliance and brackets), yet also provide space for one or more teeth to move, without obstruction, between an OTA and an FTA, or between an OTA and an ITA, or between two ITAs, or between an ITA and an FTA. 
     In that regard, the retainer body may be configured to have a shape and dimension that corresponds to and fits over the patient&#39;s current teeth arrangement (with an appliance and brackets), with sufficiently tight fitting portions on at least some of the teeth covered by the retainer body to hold the retainer onto the teeth, yet also include sufficient spacing adjacent one or more of the teeth to allow the teeth to move (due to the action of an appliance) without obstruction or friction from retainer body. For example, a clearance or spacing may be provided adjacent one or more of the teeth, to allow teeth movement, where the spacing may be uniform along some or all of the retainer body, or may vary along the retainer body so as to be different for different teeth locations. A clearance or spacing of, for example, 0.2 mm may be provided adjacent one or more teeth that are being moved by an underlying appliance. In other examples, the clearance or spacing may range from about 0.1 mm to about 0.3 mm. In other examples, other suitable clearance or spacing may be used. 
     The retainer body may have a relatively smooth outer surface that avoids or minimizes contact between the patient&#39;s tongue or cheek and sharp or protruding portions of the appliance or brackets. In further examples, comfort covers may have sufficient rigidity to provide splints for treating certain conditions, such as, but not limited to temporomandibular joint (TMJ) conditions. In further examples, comfort covers may be configured to provide additional protection of the patient&#39;s teeth or appliances secured to the teeth, for example, in sports or other activities, similar to a sports mouth guard. 
     The retainer body may be formed of any suitable material, such as, but not limited to a flexible, plastic or thermoplastic material, a rubber, a metal, a composite material, or the like, or combinations thereof. The retainer body may be made by any suitable manufacturing process including, but not limited to molding, transforming or suck down machine, 3D printing, machining, or the like. 
     CONCLUSION 
     Although many of the embodiments are described above primarily with respect to systems, devices, and methods for orthodontic appliances positioned on a lingual side of a patient&#39;s teeth, the technology is applicable to other applications and/or other approaches, such as orthodontic appliances positioned on a facial side of the patient&#39;s teeth. Moreover, other embodiments in addition to those described herein are within the scope of the technology. Additionally, several other embodiments of the technology can have different configurations, components, or procedures than those described herein. A person of ordinary skill in the art, therefore, will accordingly understand that the technology can have other embodiments with additional elements, or the technology can have other embodiments without several of the features shown and described above with reference to  FIGS. 1A-134 . 
     The descriptions of embodiments of the technology are not intended to be exhaustive or to limit the technology to the precise form disclosed above. Where the context permits, singular or plural terms may also include the plural or singular term, respectively. For example, embodiments described herein as using multiple coupling arms may just as well be modified to include fewer (e.g., one) or more (e.g., three) coupling arms. Although specific embodiments of, and examples for, the technology are described above for illustrative purposes, various equivalent modifications are possible within the scope of the technology, as those skilled in the relevant art will recognize. For example, while steps are presented in a given order, alternative embodiments may perform steps in a different order. The various embodiments described herein may also be combined to provide further embodiments. 
     Moreover, unless the word “or” is expressly limited to mean only a single item exclusive from the other items in reference to a list of two or more items, then the use of “or” in such a list is to be interpreted as including (a) any single item in the list, (b) all of the items in the list, or (c) any combination of the items in the list. Additionally, the term “comprising” is used throughout to mean including at least the recited feature(s) such that any greater number of the same feature and/or additional types of other features are not precluded. It will also be appreciated that specific embodiments have been described herein for purposes of illustration, but that various modifications may be made without deviating from the technology. Further, while advantages associated with certain embodiments of the technology have been described in the context of those embodiments, other embodiments may also exhibit such advantages, and not all embodiments need necessarily exhibit such advantages to fall within the scope of the technology. Accordingly, the disclosure and associated technology can encompass other embodiments not expressly shown or described herein.