Abstract:
An oral appliance that attaches to molars or bicuspids and that combines the capability for side-to-side and front-to-back expansion capability in one unite as a self-stopping mechanism. Further, this embodiment can be activated to compress or expand and be deactivated in two planes of side-to-side or front-to-back, along three different arms/bridges respectively. This is to say that one arm can compress front-to-back while the other arm expands, the jaw/teeth front-to-back, simultaneously). With proper arrangements and anchorage preparation the device shown and described can move front teeth forward or backward or back teeth forward or backward independently on either side of the mouth.

Description:
RELATED APPLICATIONS 
       [0001]    This application is a continuation-in-part of application Ser. No. 14/931,566 filed on Nov. 3, 2015, which in turns claims benefit of provisional application Ser. No. 62/074,360 filed Nov. 3, 2014, and also claims benefit of co-pending provisional application Ser. No. 62/502,086 filed on May 5, 2017, all of which are incorporated by reference as if fully set forth herein. 
     
    
     BACKGROUND 
       [0002]    Orthodontists, dental practitioners and medical-dental researchers are constantly searching for new and improved ways to correct the problem of constriction of the dental arches that also contributes to the overcrowding or overlapping of teeth. This condition by narrowing of the tongue space and retraction of the tongue back to the airway can cause the constriction of the upper airway in the retropalatal (behind the palate), retroglossal (behind the tongue) and hypoglossal (behind and below the tongue) area. As a result, the upper airway of the patient becomes constricted and causes resistance to the air passage, especially during the deeper stage of sleep when the upper airway muscles relax and cannot provide ideal support for the patency of the airway. 
         [0003]    In the past, many different methods have been used in order to alleviate the constriction and collapse of dental arches and dental crowding. One method that has been utilized by orthodontic practitioners is that of dental expansion of the upper and lower dental arch as well as dental and or orthopedic expansion of the upper jaw in transverse direction. There have been also attempts to do so by front-to-back expansion of the dental arches by advancing the upper or lower anterior teeth forward or distalizing (retracting) the upper and lower back teeth further backward. Although the combination of these two protocols means expansion in transverse and front to back plane of space and makes more logical process, there have not been any appliance designs capable of combining these two protocols. 
         [0004]    One dental arch expander device on the market today is a lower lingual arch to advance mandibular incisors. It does not require activation or de-activation chair side adjustments. This appliance is capable of front-to-back expansion only. As result, it cannot expand the side to side or transverse relationship of dental arch. Another drawback of this system is that it needs to be customized for each patient (e.g., in a laboratory) and cannot be provided in a kit for a chairside use. 
         [0005]    Another dental arch expander device that is on the market today is depicted in  FIG. 1  and sometimes is referred to as the Arnold expander device. The Arnold expander device  100  develops the arch using a spring-loaded split-lingual arch housed in a tube. More specifically, the Arnold expander device  100  includes a wire  102 , a spring coil  104 , a tube  106 , and bands  108 . The spring coil  104  passes into the tube  106  to create the spring-loaded split-lingual arch. The bands  108  anchor the device  100  to the patient&#39;s molar teeth. Tension on the spring coil  104  is set before the device  100  is initially placed. Further adjustment is not usually necessary. Once the desired space has been created, the appliance can be made passive by carefully pinching the tube  106  tight against the wire  102  with a pair of heavy wire cutters or tube crimping pliers. This device  100  is not capable of advancing the dental arches from back to front or distalizing the back teeth. 
       SUMMARY 
       [0006]    This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. 
         [0007]    Embodiments of dental arch and airway expander devices described herein provide improved orthodontic appliances for use in nasal cavity and/or dental arch expansion for the purpose of correcting dental crowding and/or providing tongue space for treating the upper airway constriction caused by retraction of the tongue and constriction of the nasal cavity. In some embodiments, the appliance includes left and right molar attachment portions, each of which, in some embodiments, is securable to the patient&#39;s left or right first or second molars on the right and left side of the mouth in the upper or lower jaw. In some embodiments, there are sliding wires that connect to the tongue side of the molar bands using removable tubes. In some embodiments, each tube has two inserts that slide vertically to slots soldered or otherwise attached to the tongue side of the attachment portions. In some embodiments, sliding wires that connect to the tongue side of the attachment portions using non-removable connection tubes are soldered or otherwise attached to the lingual side of the attachment portions. A sheath can be provided in a front area behind the upper and lower front teeth of the appliance to connect the right and left extensions of the wires. This sheath provides a sliding slot as a telescopic system such that the anterior ends of the wires, bent as hooks in some embodiments, can slide freely toward or away from each other for purpose of expansion or constriction. In some embodiments, there are two loaded springs (e.g., compression springs) sliding freely over the right and left side wire compressed between the connector tubes attached to the attachment portions and the sheath in front. These loaded springs can be used to produce an outward force between the connector tubes coupled to the left and right attachment portions in the back and front connector tube behind the anterior teeth. The term “anterior teeth” refers essentially to the canines and incisors. 
         [0008]    In some embodiments, sliding wires connect to the tongue side of the attachment portions using removable connector tubes. In some embodiments, each tube has two inserts that slide vertically to slots soldered or otherwise attached to the tongue side of the attachment portions. This connector tube provides a sliding slot as a telescopic system such that the posterior end of the sliding wires on each side of mouth, bent as hooks in some embodiments, can slide freely backward or forward for purpose of sagittal (front-to-back) expansion or constriction of the dental arch. In some embodiments, there are two loaded springs sliding freely over the right and left side wires compressed between the posterior connector tubes attached to the attachment portions and the sheath in front. These springs can be used to produce an expansion or constriction spring force in a sagittal direction between the anterior sheath and posterior connection tubes connected to the left and right attachment portions. 
         [0009]    In one example, the connector tubes are coupled to the attachment portions via an attachment system for easy attachment and removal of the connector tubes to and from the attachment portions. In one example, the attachment system has self-locking capability. Also, as a safety feature, the connector tubes and attachment portions can be locked with wire to prevent unintended disengagement of the connector tubes from the attachment portions. In one example, the attachment portions include bonding that bonds the connector tubes to the lingual side of the patient&#39;s molars. In one example, a portion of the connector tubes is flat with no inserts for proper fit of the connector tubes to the lingual surfaces of first or second upper or lower molars. In this design, the flat end of tubes can be bonded to the lingual surface of first or second molars with no need for the attachment portions to include a band around the molars. This option makes the appliance esthetically enhanced with no features extending on the labial surface of the molars. In some embodiments, the connector tubes are soldered or otherwise fixedly attached to the tongue side of molar bands of the attachment portions. 
         [0010]    In one example, the connector tubes are coupled to the attachment portions using an attachment system for easy attachment and removal of the connector tubes to and from the attachment portions. In one example, the attachment system has self-locking capability. Also, as a safety feature, the connector tubes and attachment portions can be locked with wire to prevent unintended disengagement of the connector tubes from the attachment portions. One benefit to this appliance is that it requires less maintenance and has fewer parts, therefore being less cumbersome and more cosmetically appealing for the patient. Another benefit is that the appliance is less expensive because it requires less hardware and maintenance. 
         [0011]    Embodiments of dental arch and airway expander appliances described herein create lateral expansion of the nasal cavity as well as lateral expansion or constriction of the posterior teeth (second and first molars, second and first bicuspids) while advancing the position of the anterior teeth (canines and incisors) and distalizing (or moving back) the posterior teeth. Once the posterior teeth are expanded to their desired position, either the expander device stops further expansion automatically as determined by the set size of expansion width or can be inactivated. Adjustments of the expander device can be made without removal from the patient&#39;s mouth. The insertion assembly to the molar tubes is removable for adjustment without damage or discomfort to the patient. 
         [0012]    Further, the position of the device behind the teeth on the roof of the mouth or floor of the mouth along with the singular connection to the molar bands creates a device that is less obtrusive to the patient and therefore more cosmetically desirable. A singular connection point on the lingual side of the molar band also allows for connection of various devices, such as braces or headgear, to the buccal side of the band. 
         [0013]    In another example, the sheath placed lingual to incisor teeth along with sliding wires can be curved to conform to the lingual side of the incisors. This alteration can be done at the chairside in the beginning or during the treatment progress. This option provides more ideal positioning of the incisors and canines during or at the completion of the advancement of the anterior teeth. 
         [0014]    In some embodiments, these attachment portions include bonding or cementation on the occlusal and/or labial surface of upper or lower first or second bicuspids, can be used in conjunction with class two or class three type mechanical devices or rubber bands to be utilized to advance or retract that dental arch in relationship to the opposite dental arch in sagittal direction for proper improvement of class two or class three malocclusions to class one relationship. This option, combined with use of fixed type three or type two mechanical devices, reduces the patient&#39;s noncompliance failure. 
         [0015]    In embodiments, springs form a part of the device and are used to apply a user determined amount of pushing or pulling force to the teeth being treated.  FIGS. 8 and 9  show an embodiment that combines side-to-side and front-to-back expansion capability in one unite as self-stopping mechanism. Further, this embodiment can be activated to compress or expand and be deactivated in two planes of side-to-side or front-to-back, along three different arms/bridges respectively. This is to say that one arm can compress front-to-back while the other arm expands, the jaw/teeth front-to-back, simultaneously). With proper arrangements and anchorage preparation the device shown and described can move front teeth forward or backward or back teeth forward or backward independently on either side of the mouth. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0016]    The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein: 
           [0017]      FIG. 1  depicts a prior art dental arch expander device; 
           [0018]      FIG. 2A  depicts a view of an embodiment of a dental arch and airway expander orthodontic appliance, in accordance with the embodiments disclosed herein, being worn on the upper jaw and teeth of a patient; 
           [0019]      FIG. 2B  depicts a bottom view of the arch portion of the dental arch and airway expander orthodontic appliance depicted in  FIG. 2A ; 
           [0020]      FIG. 2C  depicts a view of upper jaw and teeth of a patient with first molar bands of the dental arch and airway expander orthodontic appliance depicted in  FIG. 2A ; 
           [0021]      FIG. 2D  depicts a view of a molar tooth of a patient with first molar band of the dental arch and airway expander orthodontic appliance depicted in  FIG. 2A ; 
           [0022]      FIG. 2E  depicts another view of a molar tooth of a patient with first molar band, in accordance with the embodiments disclosed herein; 
           [0023]      FIG. 3  depicts a view of another embodiment of a dental arch and airway expander orthodontic appliance, in accordance with embodiments disclosed herein, being worn on the lower jaw and teeth of a patient; 
           [0024]      FIG. 4A  depicts a view of another embodiment of a dental arch and airway expander orthodontic appliance. 
           [0025]      FIG. 4B  depicts a view of the bottom of another embodiment of the appliance depicted in  FIG. 4A ; 
           [0026]      FIG. 5A  depicts a view of a top of another embodiment of a dental arch and airway expander orthodontic appliance; 
           [0027]      FIG. 5B  depicts a bottom of view of the embodiment of the appliance depicted in  FIG. 5A ; 
           [0028]      FIG. 5C  depicts the appliance depicted in  FIG. 5A  with attachment portions as bonding to lower teeth of a patient; 
           [0029]      FIGS. 6A and 6B  depict embodiments of ball hinged pads, usable in accordance with any of the bonding mechanisms described herein; 
           [0030]      FIGS. 7A and 7B  depict top and cross-sectional views, respectively, of a connecting system for connecting various conventional orthodontic devices when the attachment portion does not include a band around the molar or bicuspids; 
           [0031]      FIG. 8  is a bottom view of an alternative embodiment of dental arch and airway expander orthodontic appliance, being worn on the upper jaw and teeth of a patient; 
           [0032]      FIG. 9  is an expanded detail view of a portion of the expander of  FIG. 8 . 
       
    
    
     DETAILED DESCRIPTION 
       [0033]    The process of dental arch development is designed to move the back teeth posteriorly as well as laterally and front teeth anteriorly in the mouth to allow room for the other teeth and to expand the circumference of the dental arches larger to correct the dental crowding and to accommodate space for the volume of tongue allowing the forward positioning of the tongue out of the pharyngeal air space. When designing a product to perform this lateral and backward and frontal positioning of the teeth, two factors may be considered. The first factor is how to make a product that performs this type of tooth movement in an efficient manner. The second factor is how to make a product that is functional for the user, comfortable for patient, as well as cosmetically appealing without inhibiting the tooth movement process. 
         [0034]    For effectiveness and convenience of practitioner and patient, a dental arch and airway expander orthodontic appliance should limit periodic activation or deactivation by chair side adjustments, but at the same time have self-limiting capability to avoid unwanted expansion and/or advancement of the teeth. The self-limiting capability avoids unwanted movements in case the patient misses an appointment to be checked by the practitioner. When patient compliance is an issue, a fixed appliance is always preferred. 
         [0035]    Once the desired lateral expansion has been created, the appliance should either stop by its self-limiting capability, be made passive by carefully pinching the sheath tight on both sides against the wire with a pair of heavy wire cutters or tube crimping pliers, or tying the sliding wires inside of the tube using a stainless ligature wire. 
         [0036]    Once the desired sagittal expansion and space has been created, the appliance should either stop on its own, be made passive by carefully bending the sliding wire behind the tube attached to the first and second molars, or tying the bent end of the sliding wires inside of the connector tubes using stainless ligature wire to a hook which is welded to the inside of the molar bands. 
         [0037]      FIG. 2A  illustrates an embodiment of a dental arch and airway expander orthodontic appliance  200 .  FIG. 2A  depicts the upper palate of a patient with the appliance  200  resting on the lingual side of the upper teeth. The appliance  200  includes an arch portion  202  on the lingual side of the upper teeth and attachment portions  204  attached to the patient&#39;s first molars. In the embodiment shown in  FIG. 2A , the appliance  200  has a U shape that is fitted to the patient&#39;s upper or lower teeth. In some embodiments, including the embodiment shown in  FIG. 2A , the appliance  200  includes left and right halves that are symmetrical. 
         [0038]    The arch portion  202 , which is depicted in greater detail in  FIG. 2B , includes two sliding wires  206  that pass inside of connector tubes  208 . In some embodiments, the sliding wires  206  are stainless steel wires. The connector tubes  208  are configured to be coupled to the attachment portions  204 . In some embodiments, each of the connector tubes  208  includes one or more inserts  220  configured to couple the connector tubes  208  to the attachment portions  204 . Each of the wires  206  extends into a sheath  210  which is positioned inside of the anterior teeth. In some embodiments, the sheaths  210  are stainless steel sheaths. Each of the sheaths  210  has an opening  212 . In some embodiments, the openings  212  are positioned to face the palate or floor of the mouth of the patient. Each of the wires  206  has an anterior end  214  in the front of the mouth that is bent into the opening  212 . The wires  206  are capable of sliding freely inside of the sheaths  210  until the anterior ends  214  contact the sides of the openings  212 . In the depicted embodiment, the sheaths  210  include seams  250 . In practical implementation, the sheaths  210  may originally be in an open configuration with the seams  250  open such that the wires  206  may be inserted into the sheaths  210 . Then, after the wires  206  are inserted into the sheaths  210 , the seams  250  can be closed to the configuration shown in  FIG. 2B  so that the wires  206  are kept in place. 
         [0039]    Loaded springs  216  are located around the wires  206  between the connector tubes  208  and the sheaths  210 . The sheaths  210  are used for holding and connecting the anterior ends  214  of the wires  206  when the force generated by the expansion springs  216  expands. The sheaths  210  connect the two halves of the appliance  200  and maintain relative spacing between the wires  206 . In some embodiments, the sheaths  210  are integrally formed as a single piece. The lengths of openings  212  in the sheaths  210  determine the maximum expansion width of the appliance  200 . The anterior ends  214  of the wires  206  slide inside the sheaths  210  by force generated by the loaded springs  216  until the bent anterior ends  214  touch the right or left side of the openings  212 . In this way, the openings  212  in the sheaths  210  function as stops to limit the maximum lateral expansion of the appliance  200 . 
         [0040]    In some embodiments, when in place and fully activated, the wires  206  laterally extend within the sheaths  210  inside of the upper or lower anterior teeth directly behind the incisors with a 2- to 3-mm space left between the sheaths  210  and the bicuspid teeth. In some embodiments, the anterior ends  214  of the wires  206  are prefabricated with a bent formation in the last 1.5 mm. In some embodiments, the anterior ends  214  are positioned inside of the openings  212  of sheaths  210 , the wires  206  extend laterally to almost touching the first bicuspids, and then the wires  206  are bent distally and toward the back of mouth. The wires  206  extend and pass through the inside of the connector tubes  208 . In some embodiments, the wires  206  extend between  6  mm and  10  mm toward the back of the mouth. 
         [0041]    In the embodiment shown, the wires  206  have posterior ends  218  that are bent toward the roof or floor of the patient&#39;s mouth. In some embodiments, the bend at the posterior ends  218  of the wires  206  is about 90 degrees. In some embodiments, the bend at the posterior ends  218  is either prefabricated or made by the clinician at the time of installation of the device in the patient&#39;s mouth. The bent posterior ends  218  function as self-limiting stops. In the depicted embodiment, the force of the expander springs  216  causes the wires  206  to slide in the connector tubes  208  until the bent posterior ends  218  of the wires  206  touch the distal ends of the connecting tubes  208 . In some embodiments, the location of the bends on the posterior ends  218  of the wires  206  is selected such that the bends on the posterior ends  218  of the wires  206  will reach the connector tubes  208  when the desired advancement of the anterior teeth is reached. If during the treatment, a clinician determines that enough advancement of the anterior teeth has been acquired, the clinician can create a bend in one or both of the wires  206  extending distal of the connector tubes  208  at the chairside without removal of the device. Creating such a bend can prevent further advancement of the anterior teeth. This is a significant advantage over other devices, such as the device  100  which does not have self-limiting capability, allowing overextension of the wire  102  to disengage the wire  102  from the tube  106  and leave the spring coil  104  loose. 
         [0042]    During installation of the appliance  200 , the connector tubes  208  are coupled to the attachment portions  204 . The attachment portions  204  are depicted in greater detail in  FIGS. 2C and 2D . Each of the attachment portions  204  include a band  222  configured to be anchored on one of the patient&#39;s teeth (e.g., on a molar). The attachment portions  204  include slots  224  located on an inward portion of the bands  222 . In one embodiment, the slots  224  are oriented in a vertical from occlusal to gingival direction on the lingual side of the first molars in maxillary and mandibular arches. Each slot  224  is open at least on the occlusal and/or gingival end to accommodate insertion of the inserts  220  into the slots  224 . In some embodiments, the slots  224  are located approximately at the middle of the lingual part of the bands  222  horizontally and the openings are directed vertically, with the opening of the slots  224  at the middle of vertical height of the bands  222  on the lingual side of the first molar. In some embodiments, the location of the slots  224  is prefabricated and welded to the band  222  in the factory or can be welded in the lab later. In other embodiments, the connector tube  208  is welded to the band  222  in the lab to form a coupling between the arch portion  202  and the attachment portions  204  without the use of the inserts  220  and the slots  224 . 
         [0043]    In some embodiments, the inserts  220  of the connector tubes  208  are removably insertable into and securely coupled to the slots  224  on the patient&#39;s first or second molars. An embodiment of a connector tube  208  coupled to an attachment portion  204  is depicted in  FIG. 2E . In the embodiment shown, each of the inserts  220  has a locking mechanism  226  that, after passing through the slots  224 , extend beyond the opening of the slots  224  by spring activation to prevent unintended dislodging of the inserts  220  from the slots  224 . In some embodiments, the inserts  220  also include an unlocking mechanism  228  configured to permit the inserts  220  to be removed from the slots  224 . In the embodiment shown in  FIG. 2E , the unlocking mechanisms  228  are in the form of slots below the locking mechanisms  226 . A tool (e.g., a wire director device) can be inserted into the unlocking mechanisms  228  and used to push the inserts  220  towards each other. This motion pushes the locking mechanisms  226  into the slots  224  such that the inserts  220  can be removed from the slots  224  for removal of the connector tube  208  from the attachment portion  204 . 
         [0044]    In the embodiments depicted in  FIGS. 2A and 2C to 2E , the each of the attachment portions  204  includes a hook  230  coupled to the lingual side of the band  222 . Each connector tube  208  has, on the occlusal side, a notch  232 . The hook  230  and the notch  232  are usable for further preventing against any unintended disengaging of the connector tube  208  from the attachment portions  204 . More specifically, a practitioner may wind a wire around the hook  230  and the notch  232  to prevent relative motion of the connector tube  208  and the band  222 . In some embodiments, the bands  222  also have a connecting piece  234  attached to its buccal side. The connecting pieces  234  are attachable to various conventional orthodontic devices, such as wires in braces or connection assemblies from other class II mechanisms, class III mechanisms, or any other class of mechanisms. 
         [0045]    In some embodiments of constructing the arch portion  202 , the wire  206  is inserted into the sheath  210 , through the loaded spring  216 , and then into the connector tube  208 . To install the arch portion  202  on the attachment portions  204 , the inserts  220  of the connector tubes  208  are inserted into the slots  224  of the attachment portions  204 . In some embodiments, the wire  206  has a diameter in a range from about 0.030 inches to about 0.060 inches. In some embodiments, the wire  206  extends posteriorly towards the molars approximately parallel to the lingual side of the molars. The posterior end of wire  206  passes through the connector tubes  208  attached to the molar band and, in some embodiments, extends about 6 mm to 10 mm beyond the distal portion of the connector tubes  208 . At the posterior ends  218  of the wire  206 , the wire  206  bends vertically about 1 mm. In some embodiments, the posterior ends  218  are slightly slanted laterally to avoid irritating the patient&#39;s tongue. In some embodiments, the inserts  220  of the connector tubes  208 , which are inserted in the slots  224  welded on the inside of the bands  222 , are secured by tying a wire ligature around the notch  232  on the occlusal portion of the connector tubes  208  and around the hook  230  and/or to extension of the inserts  220  that extend beyond the slots  224 . When wire  206  is in place, the expansion spring  216  maintains contact at one end with the open end of the sheath  210  and on the other end to the connector tube  208 . 
         [0046]    An alternate embodiment of a dental arch and airway expander orthodontic appliance  300  is depicted in  FIG. 3 . The appliance  300  includes an arch portion  302  on the lingual side of patient&#39;s teeth and attachment portions  304  attached to the patient&#39;s molars. The arch portion  302  includes wires  306  that pass inside of connector tubes  308 . The connector tubes  308  are configured to be coupled to the attachment portions  304 . The wires  306  extend into a sheath  310  which is positioned inside of the anterior teeth. The wires pass inside the sheaths  310 . The sheaths  310  have openings  312  through which anterior ends  314  of the wires  306  are permitted to extend. The wires  306  are capable of sliding freely inside of the connector tubes  308  and inside of the sheath  310 . Loaded springs  316  are located around the wire  306  between the connector tubes  308  and the sheath  310 . In some embodiments, the attachment portions  304  and the connector tubes  308  are similar to the attachment portions  204  and the connector tubes  208  described above. 
         [0047]    In the depicted embodiment, the attachment portions  304  include bonding medium  348  configured to attach the connector tubes  308  to the occlusal surface of molar, or bicuspids. In some embodiments, the connector tubes  308  include one or more bonding mechanisms, such as a single mesh layer, a double mesh layer, a bonding pad, a hinged boding pad, or any other mechanism to aid in the attachment of the bonding medium  348  to the connector tubes  308 . Such bonding mechanisms are described in greater detail below with respect to  FIGS. 5A and 5B . 
         [0048]    In the embodiment shown in  FIG. 3 , the appliance  300  is configured to expand laterally as the wires slide within the sheaths  310  in response to the force exerted by the loaded springs  316 . In other embodiments, the appliance  300  is configured to expand sagittally as the wire  306  slides within the connector tubes  308  in response to the force exerted by the loaded springs  316 . In contrast to the expander device  100  depicted in  FIG. 1 , the lateral and sagittal expansion of the appliance  300  can be relatively symmetrical with substantially similar forces exerted by each of the loaded springs  316 . The lateral and sagittal expansion of the appliance  300  can also be intentionally asymmetrical with substantially dissimilar forces exerted by each of the loaded springs  316 . In some embodiments, the wires  306  are formed as two wires  306  where the anterior ends  314  of the two wires  306  are bent and located in openings  312  of the sheath  310  and the posterior ends  318  of the two wires  306  are bent after the two wires  306  are fed through the connector tubes  308 . 
         [0049]    An alternate embodiment of an arch portion  402  of a dental arch and airway expander orthodontic appliance is depicted in  FIGS. 4A and 4B . The arch portion  402  includes connector tubes  408  that are closed at the posterior end. Posterior ends  418  of wires  402  pass through anterior openings of the connector tubes  408 . The posterior ends  418  are bent through openings  436  in the connector tubes  408 . In some embodiments, the posterior ends  418  are bent vertically about 1 mm and slightly slanted laterally to avoid irritating the patient&#39;s tongue. In some embodiments, the posterior ends  418  of the wires  406  are capable of sliding about 6 mm to 10 mm inside the openings  436  of the connector tubes  408 . 
         [0050]    Each of the wires  406  extends into a sheath  410  which is positioned inside of the anterior teeth. Each of the sheaths  410  has an opening  412 . In some embodiments, the openings  412  are positioned to face the palate or floor of the mouth of the patient. Each of the wires  406  has an anterior end  414  in the front of the mouth that is bent into the opening  412 . The wires  406  are capable of sliding freely inside of the sheaths  410  until the anterior ends  414  contact the sides of the openings  412 . Loaded springs  416  are located around the wires  406  between the connector tubes  408  and the sheaths  410 . The force generated by the loaded springs  416  causes the patient&#39;s arch to expand laterally as the anterior ends  414  of the wires  406  slide within the openings  412  of the sheath  410 . The force generated by the loaded springs  416  also causes the patient&#39;s arch to expand sagittally as the posterior ends  418  of the wires  406  slide within the openings  436  of the connector tubes  408 . 
         [0051]    In some embodiments, the connector tubes  408 , which are closed at their posterior end, are coupled to attachment portions (e.g., attachment portions  204  depicted in  FIG. 2A ). The posterior ends  418  of the wires  406  are bent (e.g., in the last 1.5 mm) and positioned inside of the openings  436  of connector tubes  408 . The wires  406  extend anteriorly to almost touching the first bicuspids then bend inwardly and extend and pass through inside the sheath  410 . In case the full advancement capability of appliance is desired, then this process continues until the bent posterior ends  418  of the wires  406  are touching the front sides of the openings  436  inside connector tube  408 , preventing further withdrawal of the wire  406  from the connector tube  408 , and thereby limiting spread of the patient&#39;s anterior teeth to this predetermined extent. The posterior ends  418  act as self-limiting stops by touching the anterior portion of the openings  436  in connecting tubes  408  when the desired advancement of the anterior teeth is reached. 
         [0052]    In  FIG. 4A , the bent anterior ends  414  of the wires  406  and the bent posterior ends  418  of the wires  406  are free to slide within the sheaths  410  and the connector tubes  408 . If, during treatment, a clinician determines that enough advancement of the anterior teeth has been acquired, the clinician may tie the bent anterior ends  414  of the wires  406  together and/or the bent posterior ends  418  of the wires  406  to inserts  420  or to any other portion of the arch portion  402 , such as posterior notes (e.g., to posterior notches  544  discussed below) to prevent further expansion of the arch portion  410  laterally and/or sagitally. In  FIG. 4B , a first wire  438  is tied between the bent anterior ends  414  of the wires  406 . The first wire  438  prevents lateral expansion of the arch portion  402  because the first wire  438  does not permit the wires  406  to move away from each other. In case where lateral constriction of the dental arch is desired, the first wire  438  shown in  FIG. 4B  can be replaced by constricting elastic or spring between the bent anterior ends  414  of the wires  406 . The elastic or spring is configured to constrict the arch portion  402  because the elastic or spring pulls the wires  402  toward each other if the constriction of the dental arch is desired to close existing spaces. In this case where lateral constriction of the dental arch is desired, the springs  416  may be removed, cut, or otherwise inactivated such that the springs  416  do not exert an expanding lateral force on the arch portion  402 . 
         [0053]    Second wires  440  are tied between the bent posterior ends  418  of the wires  406  and inserts  420  on the connector tubes  408 . The second wires  440  prevent sagittal expansion of the arch portion  402  because the second wires  440  do not permit the wires  406  to move away from the connector tubes  408 . In other embodiments, the clinician can tie the bent posterior ends  418  of the wires  406  to hooks  456  extending from the connector tubes  408 . In one embodiment, the posterior end  418  of each wire  406  that is received within the connector tube  408  is bent in the shape of a hook. By tying these bent posterior ends  418  using a stainless steel second wire to the hook of the attachment portion, the advancement or distalization expansion of the appliance can be stopped short of final expansion limit. In an alternative embodiment, the posterior ends  418  of the wires  406  which extend beyond the connector tubes  408  may be removed, which may make it easier for some patients to tolerate the appliance. 
         [0054]    In the case where sagittal constriction of the dental arch is desired, the second wires  440  may be replaced by constricting elastic or springs, which are tied between the bent posterior ends  418  of the wires  406  and inserts  420  on the connector tubes  408 . The elastic or spring is configured to pull the wires  406  toward the connector tubes  408  to constrict the arch portion  402  in a sagittal direction. In other embodiments, the clinician can tie the bent posterior ends  418  of the wires  406  to hooks  456  extending from the connector tubes  408  using elastic or springs that may allow for sagittal constriction of the arch portion  402 . In one embodiment, the posterior end  418  of each wire  406  that is received within the connector tube  408  is bent in the shape of a hook. By tying these bent posterior ends  418  using constricting elastics or springs to the hook of the attachment portion, the front teeth can be retracted back and/or the posterior teeth can be protracted forward. In this case, the springs  416  may be removed, cut, or otherwise inactivated such that the springs  416  do not exert an expanding sagittal force on the arch portion  402 . 
         [0055]    An alternate embodiment of an arch portion  502  of a dental arch and airway expander orthodontic appliance  500  is depicted in  FIGS. 5A and 5B . The appliance  500  placed in a patient&#39;s mouth is depicted in  FIG. 5C . The arch portion  502  includes connector tubes  508  that are closed at the posterior end. Posterior ends  518  of wires  502  pass through anterior openings of the connector tubes  508 . The posterior ends  518  are bent through openings  536  in the connector tubes  508 . Each of the wires  506  extends into a sheath  510  which is positionable inside of the anterior teeth. Each of the sheaths  510  has an opening  512 . In some embodiments, the openings  512  are positioned to face the palate or floor of the mouth of the patient. Each of the wires  506  has an anterior end  514  in the front of the mouth that is bent into the opening  512 . The wires  506  are capable of sliding freely inside of the sheaths  510  until the anterior ends  514  contact the sides of the openings  512 . Loaded springs  516  are located around the wires  506  between the connector tubes  508  and the sheaths  510 . 
         [0056]    In the embodiments shown in  FIGS. 5A and 5B , lateral expansion of the arch portion  502  is prevented by a first wire  538  and sagittal expansion of the arch portion  502  is prevented by second wires  540 . The first wire  538  is tied between the bent anterior ends  514  of the wires  506 . The first wire  538  prevents lateral expansion of the arch portion  502  because the first wire  538  does not permit the wires  506  to move away from each other. Second wires  540  are tied between the bent posterior ends  518  of the wires  506  and posterior notches  544  on the connector tubes  508 . The second wires  540  prevent sagittal expansion of the arch portion  502  because the second wires  540  do not permit the wires  506  to move away from the connector tubes  508 . In some embodiments, the arch portion  502  includes hooks  556  and the second wires  540  could be tied between the bent posterior ends  518  of the wires  506  and hooks  556  instead of the posterior notches  544 . In some cases, the posterior notches  544  will be covered with a bonding medium when placed in a patient&#39;s mouth and the hooks  556  may extend out from the bonding medium. In these cases, the hooks  556  may be usable after bonding even if the posterior notches  544  are not usable. In some embodiments, the arch portion  502  includes the hooks  556  but not the posterior notches  544  (e.g., in the case that the posterior notches  544  irritate the patient&#39;s mount). 
         [0057]    In some embodiments, the first wire  538  and the second wires  540  are placed on the arch portion  502  before the arch portion  502  is inserted into a patient&#39;s mouth to prevent premature expansion of the arch portion  502 . The first wire  538  and the second wires  540  are then removed after the arch portion  502  is inserted into a patient&#39;s mouth to permit expansion of the arch portion  502  within the patient&#39;s mouth. Each of the connector tubes  508  includes a flat portion  542 . The connector tubes do not include inserts (e.g., inserts  220 ). Instead of tying the bent posterior ends  518  of the wires  506  to inserts, a clinician can tie the posterior ends  518  of the wire  506  to the posterior notches  544  at the most posterior end of the flat portions  542  of connector tubes  508  by the second wires  540 . 
         [0058]    In the case where lateral and/or sagittal constriction of the arch portion  502  is desired, the first wire  538  and/or the second wire  540  can be replaced by an elastic or a spring configured to exert a constricting force on the bend anterior ends  514  of the wires  506  or the bend posterior ends  518  of the wires  506 , respectively. The replacement of the first wire  538  and/or the second wire  540  with an elastic and/or a spring is similar to the replacement of the first wire  438  and/or the second wire  440  with an elastic and/or a spring, as discussed above. 
         [0059]    In some embodiments, the occlusal portion of sheath  510  and/or the anterior ends of the connector tubes  508  and/or the flat portions  542  are configured to be bonded to the lingual surface of a patient&#39;s molars and/or anterior teeth. In the depicted embodiment, the anterior ends of the connector tubes  508  include bonding mechanisms  552 , the occlusal portion of sheath  510  includes a bonding mechanism  553 , and the flat portions  542  of the connector tubes  508  include bonding mechanisms  554 . In one example, one or more of the bonding mechanisms  522 - 554  is a single mesh plate, such as a seventy-micron mesh design that is welded or soldered as prefabricated design to enhance the bonding strength of bonding medium to the connector tubes  508  and/or anterior sheath  510 . In another example, a one or more of the bonding mechanisms  522 - 554  is a double mesh plate with two single mesh plates overlayed on each other. In another example, one or more of the bonding mechanisms  522 - 554  includes a surface treatment, such as a sand-blasted surface, that is configured to improve adherence of the bonding medium when bonding to the connector tubes  508  and/or anterior sheath  510 . In another example, one or more of the bonding mechanisms  522 - 554  includes a bonding pad configured to improve adherence of the bonding medium when bonding to the connector tubes  508  and/or anterior sheath  510 . In some embodiments, the bonding pad is usable in combination with other bonding mechanisms (e.g., a bonding pad with a single or double mesh layer). In another example, the one or more of the bonding mechanisms  522 - 554  includes a hinged bonding pad which is hingedly fixed to the anterior ends of the connector tubes  508 , the sheath  510 , and/or the flat portions  542 . In some examples, the hinged bonding pad includes a hinge with a vertical axis, a hinge with a horizontal axis, or a ball hinge that rotates in multiple directions. The hinged pad is configured to rotate in one or more directions and/or extended laterally to better engage the patient&#39;s tooth. Examples of ball hinged pads are described below with respect to  FIGS. 6A and 6B . 
         [0060]    Depicted in  FIG. 5C , is the appliance  500  with the arch portion  502  and the attachment portions  504 . In this embodiment, the attachment portions  504  include bonding medium  548  configured to attach the connector tubes  508  (e.g., to bonding mechanism  522  on the flat portion  542 ) to the occlusal surface of molar, or bicuspids. The bonding medium  548  prevents the displacement of the arch portion  502  toward the occlusal. In another embodiment, bonding medium  549  is configured to attach to a portion of the sheath  510  (e.g., bonding mechanism  553 ) to the lingual surface of anterior teeth including incisors and canines. The bonding medium  549  prevents displacement of the arch portion  502  toward the occlusal or facilitates the bodily movement instead of tipping of the anterior teeth in saggital expansion or constriction of the dental arch. While the bonding medium  548  is shown only with respect to the appliance  500 , any of the other appliances described herein may include an attachment portions that includes a bonding material or any other coupling mechanism instead of the insert-and-slot coupling mechanisms described above. As shown in this embodiment, the hooks  556  protrude from the bonding medium  548  and can be used to tie the bent posterior ends  518  of the wires  506 . 
         [0061]    Depicted in  FIGS. 6A and 6B  are embodiments of ball hinged pads, usable in accordance with any of the bonding mechanisms described herein.  FIG. 6A  depicts an embodiment of a bonding pad  680  with a bonding surface  682 . In some embodiments, the bonding surface  682  includes a single mesh layer, a dual mesh layer, a surface treatment, or any other bonding surface. The pad  680  is coupled to a connector tube  608  via a fixed-length ball hinge arm  684 . The fixed-length ball hinge arm  684  extends a fixed distance away from the connector tube  608  and permits the pad  680  to rotate in one or more directions to better engage the patient&#39;s tooth.  FIG. 6B  depicts an embodiment of the bonding pad  680  with the bonding surface  682 . The pad  680  is coupled to a connector tube  608  via a telescopic ball hinge arm  686 . The telescopic ball hinge arm  686  extends away from the connector tube  608  a variable length, which can be adjusted by the practitioner to an appropriate distance to engage the patient&#39;s tooth. The telescopic ball hinge arm  686  permits the pad  680  to rotate in one or more directions to better engage the patient&#39;s tooth. 
         [0062]      FIGS. 7A and 7B  depict top and cross-sectional views, respectively, of a connecting system for connecting various conventional orthodontic devices when the attachment portion does not include a band around the molar. The connecting system includes a track  760  fixedly attached to the top of a connector tube  708 . A crimpable clasp  762  is located around the track  760 . In some embodiments, the crimpable clasp  762  is slidable along the track  760  to be properly positioned. When properly located along the track, the crimpable clasp  762  can be crimped onto the track  760  by a practitioner to prevent further sliding of the crimpable clasp  762  along the track  760 . In some embodiments, the crimpable clasp  762  has a cross-sectional shape corresponding to the cross-sectional shape of the track  760 . For example, in the depicted embodiment, the track  760  has a cross-sectional “T” shape and the crimpable clasp  762  has a cross-sectional rectangular shape with an opening for the stem of the T-shaped track  760 . 
         [0063]    An extension arm  764  extends from the crimpable clasp  762  and engages an upper extension attachment  766 . The upper extension attachment  766  engages a lower extension arm  767 . The lower extension arm is coupled to a bonding pad  768  with a bonding mechanism  770  (e.g., a single layer mesh, a double layer mesh, etc.) on a surface of the pad  768  facing the connector tube  708 . The upper extension attachment  766  is configured to move telescopically with respect to the extension arm  764  such that the distance between bonding mechanism  770  and the connector tube  708  is variable. The connector tube  708  is configured to be placed on the lingual side of the tooth and the bonding mechanism  770  is configured to contact the facial side of the tooth, with the occlusal side of the tooth facing the extension arm  764 . When the upper extension attachment  766  is in the desired position (e.g., with the connector tube  708  on the lingual side of a tooth and the bonding mechanism in contact with the facial side of the tooth), a practitioner can crimp the upper extension attachment  766  on the extension arm  764  to prevent relative movement of the crimpable clasp  762  with respect to the upper extension attachment  766 . The lower extension attachment  767  is configured to move telescopically with respect to the upper extension attachment  766  such that the vertical location of bonding mechanism  770  is variable (e.g., the location of the bonding mechanism  770  can be moved to contact the bottom, middle, or top portion of the tooth). When the lower extension attachment  767  is in the desired position, a practitioner can crimp the lower extension attachment  767  on the upper extension attachment  766  to prevent relative movement of the upper extension attachment  766  with respect to the lower extension attachment  767 . 
         [0064]    The upper extension attachment  766  can slide along the extension arm  764  telescopically to a desired distance between the crimpable clasp  762  and the upper extension attachment  766 . When the upper extension arm  766  is in the desired position, a practitioner can crimp the upper extension attachment  766  on the extension arm  764  to prevent relative movement of the crimpable clasp  762  with respect to the upper extension attachment  766 . The upper extension attachment  766  engages a lower extension attachment  767 . The lower extension attachment  767  can slide along the upper extension attachment  766  telescopically to a desired distance between the upper extension attachment  766  and the lower extension attachment  767 . When the lower extension arm  767  is in the desired position, a practitioner can crimp the lower extension attachment  767  on the upper extension attachment  766  to prevent relative movement of the upper extension attachment  766  with respect to the lower extension attachment  767 . 
         [0065]    In some embodiments, the lower extension attachment  767  forms a slot  772  or other attachment mechanism. In some embodiments, a tube  773  or other attachment mechanism is coupled to the lower extension attachment  767  and the pad  768 . In some examples, the tube  773  has a width equal to or less than the upper and lower extension attachments  766  and  767 . In some embodiments, the tube  773  includes a hook  774  extending therefrom. In some examples, the hook  774  extends substantially vertically down from the tube  773 . The hook  774  is usable to secure ends of wires of arch portions described herein, to secure orthodontic appliances to the connector tube  708 , or to secure any other appliance in the patient&#39;s mouth. 
         [0066]    In some embodiments, the slot  772 , the tube  773 , and/or another attachment mechanism is configured to be connected to various other orthodontic devices, such as wires in braces or connection assemblies from other class II mechanisms, class III mechanisms, or any other class of mechanisms. In some embodiments, the cross-sectional area of the tube  773  is larger than the cross-sectional area of the slot  772 . In this embodiment, the tube  773  is able to accommodate larger wires of some orthodontic devices (e.g., class II mechanisms, class III mechanisms). In this way, the connecting system provides a connection point for coupling any other orthodontic device to the patient&#39;s teeth. In some embodiments, such as the one depicted in  FIG. 7A , multiple crimpable clasps  762  and associated extension arms  764  can be used on the same track  760  to provide multiple attachment mechanisms on the facial side of the patient&#39;s teeth. 
         [0067]    In practical implementation, the bonding mechanism  770  can be bonded to the facial side of a patient&#39;s tooth using a bonding medium. The bonding medium can further be placed over other portions of the connection system, such as over the extension arm  764  and/or the extension attachment  766 . Bonding medium on the occlusal side of the tooth over the extension arm  764  and/or the extension attachment  766  may prevent injury to the patient and/or damage to the extension arm  764  from the patient biting down. Bonding medium on the facial side of the tooth over the extension attachment  766  may prevent the extension attachment  766  from irritating the patient&#39;s check. 
         [0068]    Referring back to  FIGS. 2A to 2E , one way in which the appliance can function efficiently is make a proper initial placement of the sheaths  210 . Each of the sheaths  210  can be placed clinically such that it is located at the gingival one third of the lingual of the anterior teeth and wires  206  make a direct path to the attachment portions  204 . This placement ensures that the force created by the loaded spring  216  anchored against the molar advance the front teeth more bodily and less tipping by application of the force more toward the gingival part of the crown of the anterior teeth. 
         [0069]    In some embodiments, the loaded spring  216  is large enough to create the desired expansion forces between the sheaths  210  and the connector tubes  208  inserted to attachment portions  204 . This action causes the anterior advancement of the front teeth, transverse and horizontal expansion of the posterior teeth and distalization force on the molars to move them posteriorly. 
         [0070]    If the distalization of the molars is indicated, with proper anchorage preparation of the front teeth and bicuspids by braces, the loaded spring  216  tied to the second bicuspids and force acting on the bands  222  on the first or second molars will drive the first and second molars distally if desired. When the proper movement of the molars is complete, the spring  216  can be made passive to ensure that no mesial movement of molars takes place. The wire connecting the second bicuspids is then detached. This allows the second and first bicuspids to naturally move towards the molars under the force of connective tissues. 
         [0071]    If the constriction of the dental arches due to over-expanded upper or lower dental arch is indicated, with proper anchorage preparation of the molar and bicuspids teeth by braces, the wires  206  tied to the molar or bicuspids and force acting on the bands  222  on the first or second molars will drive the first or second molars or bicuspids lingually if desired. This can be done by use of constricting spring or rubber bands, attached to the bent anterior ends  214  of wires  206  inside the sheaths  210 . The spring  216  can be shortened periodically to allow this movement. When the proper constriction of the molars is complete, the spring  216  can be made passive to ensure that no further constriction or expansion of the back teeth horizontally takes place. 
         [0072]    To create a lateral force on the teeth, an expansion force is built into each half of the appliance. When activated, the force applied to the posterior teeth laterally by contact of the wire  206  to the back teeth, expands the posterior teeth laterally, thus putting pressure on the teeth. The force created by this action aids in the correction of constriction of the dental arch to resolve the crowding of the teeth. It also provides proper space for anterior positioning of the tongue forward and away from pharyngeal airway. Any outward lateral movement of the teeth creates more room for the teeth and tongue. The force created by this action in the upper jaw by expanding the upper jaw bones building the floor and lateral walls of the nasal cavity aids in the correction of constriction of nasal cavity by spreading the upper jaw bones outwardly to resolve the resistance to the air passage. 
         [0073]    When all tooth movement is complete, the appliance  200  is inactivated automatically and now used as a retention device to hold the lateral and frontal expansion of the dental arches. At the completion of this stage, the appliance  200  can be disconnected by cutting the wires  206  and disengaging the connections of the inserts  220  and the slots  224 . The bands  222  can be left in place and used for the continuation of orthodontic treatment. As described previously, in some embodiments, the bands  222  have connecting pieces  234  attached to their buccal side which allows for the attachment of various other types of orthodontic devices. 
         [0074]    The appliance  200  also includes structure permitting selective limitation of the degree of arch spread. Referring still to  FIG. 2 , the anterior end  214  of each wire  206  that is received within the sheath  210  is bent in the shape of a hook. By tying these anterior ends  214  (e.g., using stainless steel wire), the lateral expansion of the appliance  200  can be stopped short of final expansion limit. In case the full expansion capability of appliance is desired, then this process continues until the anterior end  214  of the wire  206  is touching the lateral side of the opening  212  inside sheath  210  preventing further withdrawal of the wire  206  from the sheath  210 , and thereby limiting spread of the patient&#39;s arch to this predetermined extent. 
         [0075]    Referring, now, to  FIGS. 8 and 9 , a further preferred embodiment of an airway expander  810  includes tooth attachment units  812  and an expandable frame  814 . Attachment units  812  are the same as attachment portions  204 , and in one preferred embodiment include a connecting piece similar to connecting piece  234 , as shown in  FIG. 2A  and described in accompanying text. Expandable frame  814  includes first and second selectively expandable arms  816 , each joined to one of the attachment units  812  and being joined together by a selectively expandable anterior bridge  820 . Each arm  816  includes an arm shaft  822  having a first end  824  attached to one of the attachment units  812  and a second end having a head  825  ( FIG. 9 ), that is expanded in transverse dimension. For each arm  816 , an arm sheath  826 , receives the head  825 , which is captured by a narrowed sheath exit  830  ( FIG. 9 ). Further, a position-adjustable block  832 , is positioned on each shaft  822  and is locked in place by a set screw  833 . A spring  834  is positioned about the shaft  822 . Each spring  834  has a first end joined to the sheath  826  and a second end joined to the block  832 . 
         [0076]    The bridge  820  includes a first bridge shaft  840  attached to a first one of the arm sheaths  826 . Shaft  840  bends inwardly toward the center of the patient&#39;s mouth and supports a bridge sheath  842 . A second bridge shaft  844  is attached to a second one of the arm sheaths  826  and also bends toward the center of the patients mouth. The second bridge shaft  844  terminates in a head  846  (not shown, but same as head  825 ) that is retained in sheath  842 . A spring  850  and a position adjustable block  852 , held in place by a set screw  853 , are situated on the second bridge shaft  844 . Blocks  832  and  852  may assume forms different from those shown. In one embodiment shafts  822  and  844  have helical threads and the positional adjustable blocks rotated to move in position. 
         [0077]    The advantages of the above described arrangement include the ability to push the molars backward, pull them forward, push them outwardly or even pull them inwardly. The push the molars backward, blocks  832  are moved forward, placing springs  834  into compression, and locked in place by set screws  833 . The rearward force applied to the molars is a function of the compression of springs  834  and may be set to achieve a desired result. If this action causes heads  825  to abut narrowed regions  830 , the effective length of shafts  822  may be increased by moving tooth attachment units rearwardly on shafts  822 . To pull the molars forward, blocks  834  are moved rearward to place springs  834  into tension. Similarly, to spread the molars, bridge block  852  is moved toward bridge sheath  842 . To pull molars inwardly (not a typical goal of orthodontics) block  852  is moved away from sheath  842 . Although the above discussion has been directed to molars, attachment units  812  could be attached to other types of teeth and similar procedures could be performed on, for example, the bicuspids. 
         [0078]    The methods and appliances described herein include automatic inactivation for the transverse expansion or constriction of posterior teeth, anterior advancement or retraction of the anterior teeth and distal expansion of the molars, bicuspids and canines. These methods and appliances are capable of being used for correction of the upper dental arch, upper jaw bone constriction, or lower dental arch constriction which helps to resolve the dental malposition, dental crowding, proper room for tongue position, and nasal cavity expansion for improvement of airway. In some embodiments, the appliances include loaded springs around wires connected to attachment portions with connector tubes and extended to an anterior sheath. The spring creates a distalization force on the first and/or second molars, an anterior extending force on anterior teeth (e.g., canines and incisors), and transverse expansion for the posterior teeth (e.g., canines, bicuspids, and molars). 
         [0079]    While illustrative embodiments have been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention.