Abstract:
An orthodontic appliance having improved devices for interconnecting the braces associated with a patient&#39;s upper and lower teeth. Each connecting device generally takes the form of a unitary, thin band of material that can be connected between the braces associated with the patient&#39;s upper and lower teeth to achieve the forces that are desired for a particular treatment. The connecting device generally includes a body having integral end portions that are preferably rounded for purposes of comfort. Each end portion includes an attachment for connection to the braces associated with the patient&#39;s teeth. Preferably, at least one of the attachments of each connecting device is keyed so that upon its connection to the braces, swivelling of the connecting device is effectively precluded without compromising desired movements of the connecting device relative to the orthodontic appliance and the patient&#39;s mouth. As a result, interaction between the connecting devices and the patient&#39;s jaws, lips and cheeks is minimized, and breakage is effectively precluded. The connecting device is capable of being formed of a material that can produce forces, upon use of the connecting device, that are sufficiently small to produce desired movements of the teeth without producing undesired movements of the patient&#39;s jaws.

Description:
RELATED CASE 
     This is a continuation-in-part of prior U.S. patent application Ser. No. 08/196,437, filed Feb. 15, 1994, now U.S. Pat. No. 5,435,721. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates generally to orthodontic devices for treating various malocclusions including protrusion and retrusion of the upper teeth relative to the lower teeth, and misalignments of the teeth relative to one another. 
     A variety of malocclusions have been corrected with conventionally available orthodontic appliances for achieving realignments of the teeth so that an appropriate alignment is established for the upper teeth, for the lower teeth, and between the upper and lower teeth. Early efforts involved the application of orthodontic appliances to the teeth in conjunction with elastic (rubber) bands to apply appropriate forces to the orthodontic appliance and, as a result, to the teeth, as well as removable head gear for interacting with the teeth, to achieve desired movements. Although these techniques have provided satisfactory results, they were found to be subject to certain disadvantages. 
     The greatest disadvantage of such orthodontic systems is that satisfactory results can only be obtained if a particular device is properly worn. Elastic bands and head gear are rather easily removed by the patient, at times limiting their overall effectiveness. Head gear has the further disadvantage that since it is worn externally (primarily on the top of the head or around the neck), it is cosmetically undesirable and therefore less likely to be properly worn. 
     Another disadvantage of such orthodontic systems is that they can produce undesirable side effects resulting from undesirable forces that may come to be applied to the orthodontic appliance in addition to those forces which are desired for an effective treatment to take place. These undesirable forces are most prevalent for elastic bands, at times resulting in tooth extrusion and bite opening. Head gear can also result in tooth extrusion. Elastic bands further have the disadvantage of delivering forces that can decay over time, as the elastic elements stretch and fatigue. 
     Various devices have been developed in an effort to improve upon the elastic bands and head gear of conventional orthodontic appliances. One such attempt involves the use of spring operated devices, primarily to replace the elastic bands. Such devices are disclosed, for example, in U.S. Pat. Nos. 3,618,214 (Armstrong), 4,795,342 (Jones), 5,022,855 (Jeckel) and 5,074,784 (Sterrett et al). 
     Generally speaking, such devices employ springs to establish tensions similar to those formerly established by elastic bands. However, in practice, it has been found that such devices tend to produce relatively severe and undesirable side effects leading to unwanted tooth extrusion and bite opening. Moreover, most available spring-operated devices are themselves removable (much like the elastic bands they replace), and are often either not worn, lost or broken. For those spring-operated devices that are removable, a common requirement is for the patient to remove the device to eat or to brush the teeth. For those spring-operating devices that are not removable, it is often extremely difficult to clean around such devices. In either case, such devices tend to be bulky, making it difficult for patients to talk with the appliances in place. 
     Another orthodontic device that has recently found increased acceptance is the so-called &#34;bite jumping&#34; appliance. Such appliances are disclosed, for example, in U.S. Pat. Nos. 3,798,773 (Northcutt), 4,462,800 (Jones), 4,551,095 (Mason), 4,708,646 (Jasper) and 5,183,388 (Kumar). 
     All except U.S. Pat. No. 4,708,646 disclose variations of a device generally known as the &#34;Herbst&#34; device, and include a metal cylinder containing a plunger and attachable to and between the orthodontic appliances (braces) fixed to the patient&#39;s upper and lower teeth. Such devices are rigidly attached to the associated orthodontic appliances and, as a result, cannot be removed by the patient. However, because of their rigid attachment, it is not uncommon for such devices to become damaged, or to cause damage to the orthodontic appliances to which they are attached. Primarily, this results from the lack of flexibility of such devices, and the relatively large forces that can be produced as the patient&#39;s jaws are closed (in the normal course). 
     U.S. Pat. No. 4,708,646 replaces the more conventional Herbst device with an elastic element comprised of a spring surrounded by a rubber core and having metal end caps for attachment to and between the orthodontic appliances associated with the patient&#39;s upper and lower teeth. In use, the disclosed elastic element tends to produce extremely high forces, similar to the Herbst device, and is highly susceptible to breakage. Breakage primarily results from the ability of such a device to swivel about its attachment points. This produces significant flexure and permits the device to at times become located between the patient&#39;s upper and lower teeth, allowing the device to be chewed upon (either voluntarily or involuntarily). Breakage also results from extended movement (opening) of the mouth, which tends to stretch the device and place stress on its end caps. Separation of the end caps from the connecting spring and cover is quite common as a result. 
     Also to consider is that such devices are primarily directed toward the treatment of retrusion of the lower jaw. Such appliances are not generally useful in treating malocclusions of the teeth that are not related to underlying skeletal defects (such as misalignment of the jaw). The reason for this is that favorable tooth movement is difficult to achieve in view of the relatively heavy forces that are produced by such devices. Because of this, the use of such devices can be disadvantageous when the patient has upper and lower jaws that are correctly aligned, and only movement of the patient&#39;s teeth is required (either relative to one another, or relative movement of the upper teeth and the lower teeth). As a result, such appliances can only be used in limited situations. 
     Consequently, the need remains to provide a device for developing the forces that are appropriate toward effectively interconnecting orthodontic appliances to achieve the movements that are desired for a particular treatment, and which are less subject to the disadvantages of non-use and breakage. 
     SUMMARY OF THE INVENTION 
     It is therefore the primary object of the present invention to provide an improved orthodontic appliance. 
     It is also an object of the present invention to provide an improved orthodontic appliance for the treatment of dental malocclusions including protrusion or retrusion of the upper teeth relative to the lower teeth, and misalignments of the teeth relative to one another. 
     It is also an object of the present invention to provide an orthodontic appliance having connectors that are less susceptible to breakage, and to damage of the orthodontic appliance with which they are used. 
     It is also an object of the present invention to provide an orthodontic appliance that can produce forces sufficiently small to effectively realign the teeth without adverse side effects such as concurrent movement of the jaws relative to one another. 
     It is also an object of the present invention to provide an orthodontic appliance that is sufficiently resilient, and which provides a sufficient degree of movement to achieve desired orthodontic treatments. 
     It is also an object of the present invention to provide an orthodontic appliance having characteristics that promote its being worn by the patient. 
     It is also an object of the present invention to provide an orthodontic appliance that is comfortable to wear, unobtrusive and cosmetically acceptable. 
     It is also an object of the present invention to provide an orthodontic appliance that can provide relatively consistent forces throughout a desired orthodontic procedure. 
     It is also an object of the present invention to provide an orthodontic appliance which is simple in construction, and easy to install and adjust. 
     These and other objects which will become apparent are achieved in accordance with the present invention by providing an orthodontic appliance having improved devices for interconnecting the braces associated with a patient&#39;s upper and lower teeth. Each connecting device generally takes the form of a unitary, thin band of material that can be connected between the braces associated with the patient&#39;s upper and lower teeth to achieve the forces that are desired for a particular treatment. In its principal configuration, the connecting device has a body that is substantially flat and rectangular, with integral end portions that are preferably rounded for purposes of comfort. Each end portion includes an aperture for attachment to the braces associated with the patient&#39;s teeth. In an alternative configuration, the connecting device is formed of wire, with helically formed end portions for attachment to the braces associated with the patient&#39;s teeth. 
     In either case, at least one end of each connecting device is preferably keyed so that upon its attachment to the braces, swivelling of the connecting device is effectively precluded without compromising desired movements of the connecting device relative to the orthodontic appliance and the patient&#39;s mouth. As a result, interaction between the connecting devices and the patient&#39;s jaws, lips and cheeks is minimized, and breakage is effectively precluded. The connecting device is capable of being formed of a material that can produce forces, upon use of the connecting device, that are sufficiently small to produce desired movements of the teeth without producing undesired movements of the patient&#39;s jaws. 
     For further detail, reference is made to the detailed description which is provided below, taken in conjunction with the following illustrations. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an elevational view showing an orthodontic appliance incorporating connecting devices of the present invention, as viewed from the front of the patient&#39;s mouth. 
     FIG. 2 is an elevational view showing an orthodontic appliance incorporating connecting devices of the present invention, as viewed from the side of the patient&#39;s mouth. 
     FIGS. 3A and 3B are side elevational views showing connecting devices for association with the left and right sides of the orthodontic appliance, respectively. 
     FIGS. 4A and 4B are top plan views of the connecting devices of FIGS. 3A and 3B, respectively. 
     FIGS. 5A and 5B are end views of the connecting devices of FIGS. 3A and 3B, respectively. 
     FIG. 6 is a side elevational view similar to FIG. 3a, showing an alternative embodiment connecting device having a laminated structure. 
     FIG. 7 is a top plan view similar to FIG. 4A, showing an alternative embodiment connecting device having end portions with offset apertures. 
     FIGS. 8 and 9 are elevational views similar to FIG. 2, showing alternative embodiment orthodontic appliances incorporating connecting devices of the present invention. 
     FIG. 10 is an elevational view similar to FIG. 2, showing an orthodontic appliance incorporating an alternative embodiment connecting device. 
     FIG. 11A is a side elevational view of an alternative embodiment connector for detachably receiving a connecting device. 
     FIG. 11B is an end elevational view of the connector of FIG. 11A. 
     FIGS. 12A to 12C are sequential side elevational views showing connection (and disconnection) of a connecting device with the connector of FIGS. 11A and 11B. 
     In the several views provided, like reference numbers denote similar structure. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     FIGS. 1 and 2 illustrate the upper jaw 1 and the lower jaw 2 of a hypothetical patient. Upper teeth 3 are associated with the upper jaw 1 and lower teeth 4 are associated with the lower jaw 2. An orthodontic appliance 5 is applied to and between the upper and lower teeth 3, 4 to achieve desired movements of the upper teeth 3 and/or the lower teeth 4 relative to each other. While it would also be possible to achieve movements of the upper jaw 1 and the lower jaw 2 relative to each other, the discussion which follows is primarily directed toward relative movements of the upper teeth 3 and the lower teeth 4 without associated movements of the upper jaw 1 and the lower jaw 2, as well as to movements of either the upper teeth 3 or the lower teeth 4 relative to one another. However, it is to be understood that the improvements of the present invention are applicable to any of a number of orthodontic procedures other than those which will be specifically described below. Such orthodontic procedures will be readily understood by the person of ordinary skill in the art, and are achievable by causing the various elements of the orthodontic appliance 5 to interact with the teeth 3, 4, and if desired, the jaws 1, 2, employing techniques that are themselves known and conventional. 
     The orthodontic appliance 5 is generally comprised of an upper appliance 6 associated with the upper teeth 3, a lower appliance 7 associated with the lower teeth 4, and in the illustrative embodiment shown in FIGS. 1 and 2, a pair of connecting devices 8, 9 interconnecting the upper appliance 6 and the lower appliance 7. The connecting device 8 extends between left-most portions of the upper appliance 6 and left-most portions of the lower appliance 7, while the connecting device 9 extends between right-most portions of the upper appliance 6 and right-most portions of the lower appliance 7. Specifics regarding such attachment will be discussed more fully below. 
     FIGS. 3A, 4A and 5A illustrate the connecting device 8 associated with the left-most portions of the orthodontic appliance 5. FIGS. 3B, 4B and 5B illustrate the connecting device 9 associated with the right-most portions of the orthodontic appliance 5. Overall construction of the connecting devices 8, 9 is substantially the same, except that the connecting device 8 substantially constitutes a mirror image of the connecting device 9. This is necessary for proper interaction of the connecting devices 8, 9 with the upper and lower appliances 6, 7, as will be discussed more fully below. 
     Each of the connecting devices 8, 9 is formed as a flat, substantially rectangular plate 10 having end portions 11, 12 for attachment to and between the upper and lower appliances 6, 7, respectively. Each of the end portions 11, 12 is formed as an integral portion of the plate 10, so that each of the connecting devices 8, 9 is unitary in construction. This is advantageously accomplished with flat plate materials sized to include the plate 10 and end portions 11, 12. The end portions 11, 12 can then be bent (preferably, a gradual bend) relative to the plate 10 to form the desired connecting device. Each of the end portions 11, 12 includes an aperture 13 for attachment to the upper and lower appliances 6, 7, and is preferably rounded (shown at 14) to avoid sharp edges that could irritate and possibly injure the patient&#39;s jaws, teeth, lips and cheeks. 
     The configuration of the connecting devices 8, 9 can be varied, as desired, to suit the requirements of a particular application. Preferably, connecting devices of different sizes will be produced to accommodate variations in the size of the patient&#39;s jaws 1, 2, and the associated teeth 3, 4, as well as the particular orthodontic procedure to be accomplished. The following parameters are given by way of illustration. 
     The connecting devices 8, 9 will generally have lengths of from 1.125 inches to 1.875 inches. Variations in length having increments of 0.125 inches should be sufficient for most purposes. The unitary element forming the plate 10 and the end, portions 11, 12 preferably has a thickness of from 0.005 inches to 0.090 inches. The connecting devices 8, 9 generally have widths of from 3 mm to 9 mm. A width of about 5 mm is presently considered to be preferable in most cases. 
     Different amounts of force can be achieved, primarily responsive to variations in the above parameters and the materials used to form the connecting devices 8, 9. In terms of the above-mentioned parameters, variations in width and/or thickness will primarily determine the forces that are produced by the connecting devices 8, 9. Of course, the comfort of the patient needs to be taken into consideration as well. Preferred materials for forming the connecting devices 8, 9 presently include spring stainless steel, titanium, nickel-titanium (including super-elastic nickel-titanium), copper-nickel-titanium and carbon fiber resins. However, other materials can also be used to produce the forces that are desired, provided the selected material is inert when present in the mouth of a patient. 
     The selected material can, if desired, be provided with a protective coating (e.g., plastic, rubber, epoxy or composite resins) to either ensure its inert behavior inside the patient&#39;s mouth, or for purposes of comfort and/or safety (the applied coating can even serve to entrain broken portions of the connecting device in the event of a failure). 
     As shown in FIG. 6, the selected material can also, if desired, be implemented as a multi-layered structure (a connecting device 8&#39; has been selected for illustration in the drawing) comprised of plural plate materials 10&#39;, 10&#34;, each forming a structure in all other respects similar to the connecting devices 8, 9. The several layers 10&#39;, 10&#34; are preferably joined (welded, epoxied, etc.) to form a laminate capable of providing the structural advantages of the unitary connecting devices previously described. In this configuration, the plate materials forming the layers 10&#39;, 10&#34; may have a reduced thickness on the order of 0.006 inches which, following assembly, yields a thickness (for two layers) approximating that of a connecting device 8, 9 having a single layer. 
     In any event, it is important that the material selected for use in producing the connecting devices 8, 9 have sufficient elasticity to be safe and comfortable when worn by the patient, and sufficient resiliency to produce the forces that are desired, and to recover their initial shape following the twisting and bending that will occur when associated with the orthodontic appliance 5. 
     Shaping of the end portions 11, 12 will vary not only in accordance with the orthodontic treatment that is intended, but also in accordance with the side of the patient&#39;s mouth that is to receive the connecting device. For example, to ensure that proper forces are developed, while maximizing patient comfort, it will be noted that the end portions 11, 12 of the connecting devices 8, 9 are formed so that the end portions 11, 12 depend from the associated appliances 6, 7, causing the plate 10 to lie between the appliances 6, 7. This tends to minimize extension of the connecting devices 8, 9 above the upper appliance 6 and below the lower appliance 7, or outwardly from the appliances 6, 7. For this reason, the end portions 11, 12 are preferably angled relative to the plate 10 so that the end portions 11, 12 (as well as their seam with the plate 10) will be substantially vertically oriented when associated with the orthodontic appliance 5. 
     To accomplish this, the end portions 11, 12 of the left-most connecting device 8 are preferably bent relative to the plate 10 so that each end portion forms an angle of 0 to 120 degrees (preferably, of about 60 degrees) and includes a twist of 0 to 90 degrees (preferably, of about 45 degrees). The end portions 11, 12 of the right-most connecting device 9 are preferably bent relative to the plate 10 so that each end portion forms an angle of 0 to 120 degrees (preferably, of about 60 degrees) and includes a twist of 270 to 0 degrees (preferably, of about 315 degrees). Employing parameters such as these will produce connecting devices 8, 9 similar to those shown in FIGS. 3A, 3B, 4A and 4B, with the offset end portions 11, 12 that are best shown in FIGS. 5A and 5B. In implementing the layered connecting device 8&#39; of FIG. 6, the end portions 11&#39;, 12&#39; are preferably bent relative to the layers 10&#39;, 10&#34; so that each end portion forms an angle of about 50°. 
     If appropriate for a particular orthodontic procedure, the apertures 13 of the end portions 11, 12 may be round, for engaging conventional connecting wires associated with the orthodontic appliance. However, in accordance with the present invention it has been found to be particularly advantageous to provide the connecting devices 8, 9 with apertures 13 that are in essence &#34;keyed&#34; to the connecting wires of the orthodontic appliance. 
     In particular, it has been found that swivelling of the connecting devices 8, 9 relative to the upper and lower appliances 6, 7 can be prevented by appropriately shaping the apertures 13 to engage shaped connecting wires (of the appliances 6, 7 that are to receive them). This, in turn, helps to prevent the connecting devices 8, 9 from swivelling between the upper teeth 3 and the lower teeth 4, avoiding the potential for damage of the connecting devices 8, 9 (or the orthodontic appliances 6, 7 to which they are attached) by being chewed upon by the patient. To be noted is that the flat shape of the connecting devices 8, 9 tends to permit flexing of the connecting device in only one direction (in or out of plane, but not transversely), further preventing movement of the connecting devices 8, 9 between the teeth of the patient. 
     As an example, the apertures 13 can be squared, for interacting with squared connecting wires associated with the orthodontic appliance 5. Any of a variety of shapes (polygonal, slotted, regular, irregular, etc.) can be used to achieve a similar function. If desired, the apertures 13 associated with each of the end portions 11, 12 of a particular connecting device may be shaped for interacting with the connecting wires of the orthodontic appliance 5. However, in many applications it will be sufficient to provide only one of the apertures 13 (associated with either the end portion 11 or the end portion 12) with a shaped configuration for interaction with the connecting wire of either the upper appliance 6 or the lower appliance 7, as desired. The apertures 13 associated with a particular connecting device 8, 9 can either be the same, or different in shape, depending upon preference and the orthodontic procedure to be performed. 
     Keying the apertures 13 of the connecting devices 8, 9 can also serve to ensure that the connecting device 8 is properly associated with the left-most portions of the orthodontic appliance 5 and that the connecting device 9 is correctly associated with the right-most portions of the orthodontic appliance 5. This could also be accomplished by marking the connecting devices 8, 9. However, keying the apertures 13 of the connecting devices 8, 9 has the added advantage of automatically ensuring that the connecting devices 8, 9 are properly associated with the orthodontic appliance 5. A similar result is also obtainable by providing the apertures 13 of the connecting devices 8, 9 to be associated with the upper appliance 6 with a size (e.g., diameter) that differs from the size of the apertures 13 of the connecting devices 8, 9 to be associated with the lower appliance 7. 
     The apertures 13 are capable of variation, both in terms of their size and their shape. As an example, round apertures 13 having diameters of from 1 to 4 mm (and preferably 2 mm) should be sufficient for such applications. For slotted or rectangular (keyed) apertures 13, lengths of from 0.021 to 0.125 inches and widths of from 0.017 to 0.026 inches are presently preferred. The apertures 13 associated with the ends 11, 12 of the connecting devices 8, 9 may be similar in terms of their size and shape, or dissimilar, as desired. The apertures 13 of FIGS. 3a and 3b are symmetrically positioned in the end portions 11, 12 (note FIGS. 4a and 4b), resulting in an offset (of approximately 15°) of the apertures 13 relative to each other (note FIGS. 5a and 5b). However, other (offset) positionings may be provided for different applications, if desired. As an example, FIG. 7 shows a connecting device (again, a connecting device 8&#34; has been selected for illustration) having a rounded aperture 13&#39; and a slotted aperture 13&#34; which are offset relative to the end portions 11&#34;, 12&#34;, resulting in an alignment of the offset apertures 13&#39;, 13&#34; along the longitudinal axis of the connecting device 8&#34;. 
     Referring again to FIGS. 1 and 2, attachment of the connecting devices 8, 9 to the upper and lower appliances 6, 7 (completing the orthodontic appliance 5) will now be described for the illustrative procedure that is shown. In substantially conventional fashion, the upper appliance 6 is attached to the upper teeth 3 by attaching (e.g., gluing or bonding) a plurality of supports 15 to the upper teeth 3, and by appropriately interconnecting the supports 15 with a common wire 16. The lower appliance 7 is similarly attached to the lower teeth 4 by affixing a plurality of supports 15 to the lower teeth 4, and by interconnecting the supports 15 with a common wire 17. To this point, the procedure involved is substantially conventional, and could employ any of a variety of known techniques to accomplish the desired end result. 
     The connecting devices 8, 9 are then attached to and between the appliances 6, 7, making sure to fit the connecting device 8 to the left-most portions of the orthodontic appliance 5 and the connecting device 9 to the right-most portions of the orthodontic appliance 5. To this end, and for each of the connecting devices 8, 9, the upper appliance 6 is provided with a connector 18 and the lower appliance 7 is provided with a connector 19 for receiving the end portions 11, 12 of the connecting devices 8, 9. 
     In this illustrative embodiment, the connector 18 includes a tube 20 for slidingly receiving an end of the wire 16 and a tube 21 connected to the tube 20, for receiving a connecting wire 22. The terminating end of the connecting wire 22 includes a ball stop 23, which is preferably integral with the connecting wire 22. The connector 19 employs the wire 17 of the lower appliance 7, in combination with a ball 24 (which bears against a crimpable stop 25 for slidingly receiving the wire 17) associated with the wire 17. Of course, any of a variety of known connectors may be employed, apart from the connectors 18, 19, if desired. 
     Upon assembly, the aperture 13 of the end portion 12 is engaged by the wire 17 (the connector 19) of the lower appliance 7 and the aperture 13 of the end portion 11 is engaged by the connecting wire 22 (the connector 18) associated with the upper appliance 6. The connecting wire 22 is then bent over, at 26, finishing the desired assembly. 
     Resulting from such assembly, the connecting devices 8, 9 are appropriately positioned between the connector 18 of the upper appliance 6 and the connector 19 of the lower appliance 7 so that upon closure of the jaws 1, 2, the balls 23, 24 will interact with the end portions 11, 12 of the connecting devices 8, 9, developing the compressive forces that are desired (in this case, between the upper molar area and the lower canine area) for appropriate tooth movement (e.g., in a mesial or distal direction). As the jaws 1, 2 are opened, the end portions 11, 12 are permitted to slide along the associated wires 17, 22, permitting the jaws 1, 2 to open freely. The length of the connecting devices 8, 9 will be selected so that upon closure of the jaws 1, 2, interaction between the balls 23, 24 and the connecting devices 8, 9 will urge the upper teeth 3 posteriorly relative to the lower teeth 4, achieving the desired realignment over time. 
     Referring to FIG. 8, the upper teeth 3 can be urged anteriorly relative to the lower teeth 4 by reversing the appliances 6, 7 so that the appliance 6&#39; is associated with the lower teeth 4 and so that the appliance 7&#39; is associated with the upper teeth 3. All other attachment procedures will remain substantially the same. 
     Referring to FIG. 9, it is also possible to provide either (or both) of the appliances 6, 7 (depending upon whether the upper teeth 3 or the lower teeth 4 are to be operated upon) with both a connector 18 and a connector 19, and to fit the connecting device 8, between the connectors 18, 19. The connecting device 8, can in this way operate as an intra-arch spring, by applying compressive forces between the connectors 18, 19 which can serve to separate teeth of either the upper jaw 1 or the lower jaw 2 (or both) from one another. Because relatively light forces can be produced by the connecting device 8, orthodontic appliances such as those illustrated in FIGS. 1, 2 and 6 can also be effectively used to provide an increased spacing of the teeth (i.e., enlargement of the jaw), if desired for a particular orthodontic procedure. 
     Referring back to FIG. 1, any of a variety of orthodontic procedures may be performed using techniques similar to those described above. To be noted is that irrespective of the orthodontic procedure to be performed, and the orthodontic appliance that is formed in accordance with the present invention, the connecting devices 8, 9 are caused to interact with the appliances 6, 7 so that the end portions 11, 12 can slide along the associated wires 17, 22, respectively. The connecting devices 8, 9 are permitted to pivot from side to side, and up and down, to provide desired freedom of movement during normal oral function. Generally, this will be accomplished while preventing the connecting devices 8, 9 from swivelling relative to the appliances 6, 7, (i.e. around their own axis), to reduce the potential for breakage (of the connecting devices 8, 9 or at the connectors 18, 19) and to prevent irritation and/or injury to the adjoining lips and cheeks of the patient. To this end, either the end portion 11, the end portion 12 or both end portions 11, 12 would preferably include keyed apertures 13, as previously described. 
     The foregoing improvements are achieved making use of connecting device 8, that is formed from flat, plate materials. In addition to their ease of manufacture, such materials are less subject to the fatigue previously encountered with elastic bands, ensuring that the forces applied by the connecting device 8, is substantially constant over time, as is desired. The amount of force (activation) achievable by means of the connecting devices 8, 9 can be varied either by adjusting the characteristics of the connecting devices 8, 9 as previously described, or by providing the connector 19 with plural stops instead of the single fixed stop (i.e., the crimpable stop 25) employed in conjunction with the illustrated orthodontic appliance 5. 
     Referring again to FIG. 10, foregoing improvements are also achievable making use of connecting devices 27, 28 that are formed from wire materials, if desired. As an example, FIG. 10 shows an orthodontic appliance 30 that substantially corresponds to the orthodontic appliance 5 of FIG. 2, but for the connecting devices 8, 9, which are in this case replaced with the connecting devices 27, 28. The connecting devices 27, 28 are formed of wire (e.g., nickel-titanium wire), and have end portions 31, 32 for attachment to and between the upper and lower appliances 6, 7, respectively. Each of the end portions 31, 32 is again formed as an integral portion of the connecting devices 27, 28, yielding a unitary construction. However, in this case, the unitary end portions 31, 32 are formed as helical elements for engaging the connectors 18, 19. 
     The connecting devices 27, 28 interact with the remainder of the orthodontic appliance 30 much the same as the connecting devices 8, 9 interact with the orthodontic appliance 5. Assembly of the respective components to achieve a desired result (treatment) is also substantially the same. As with the end portions 11, 12 (i.e., the apertures 13), either or both of the end portions 31, 32 may be keyed (e.g., by squaring off the helices for interaction with squared arch wires) to prevent swivelling of the connecting devices 31, 32 relative to the upper and lower appliances 6, 7, if desired. 
     FIGS. 11A and 11B show an alternative embodiment connector 35 for removably engaging a connecting device to provide a &#34;quick-connect&#34;/&#34;quick-disconnect&#34; feature. The connector 35 includes a body 37 for surrounding and engaging an arch wire 38, and an arm 39 extending from the body 37 and terminating in a clasp 40. For most applications, the body 37 of the connector 35 will slidingly engage the wire 38 to allow for movement of the connector 35 along the wire 38 responsive to opening and closing of the jaws of the patient. Suitable ball stops can be provided for limiting such movement, to achieve a particular treatment that is desired. The connecting device 36 includes a body that terminates in opposing end portions 42, 43. The end portions 42, 43 have apertures 44, 45 for interacting with the connectors that are to receive them, as will be discussed more fully below. 
     With further reference to FIG. 12A, the connectors 35 and connecting devices 36 interact with one another, and the remainder of the associated orthodontic appliance, much the same as the connectors and connecting devices previously described. Either or both end portions 42, 43 of the connecting devices 36 can be keyed to prevent swivelling relative to the orthodontic appliance that receives them. In addition, or as an alternative, the body 37 of the connector 35 is squared to mate with a squared arch wire 38, as is best shown FIG. 11A. Providing the connector with a round body would permit the connector to swivel relative to the orthodontic appliance, if desired for a particular application. However, such swivelling would tend to be limited by the subsequent attachment of the connecting device 36, as follows. 
     FIGS. 12A to 12C show the manner of connecting (and disconnecting) the previously described connector 35 and connecting device 36. As shown in FIG. 12A, the end portion 42 of the connecting device 36 has an aperture 44 configured to mate with the clasp 40 of the connector 35. Preferably, and as shown, the connecting device 36 has a slotted aperture 44 for mating with a &#34;football-shaped&#34; clasp 40. However, other corresponding shapes may be employed to achieve a similar result. As shown in FIG. 12B, the slotted aperture 44 of the connecting device 36 is positioned over the football-shaped clasp 40 of the connector 35 so that the clasp 40 enters the slotted aperture 44. Following this, and as shown in FIG. 12C, the connecting device 36 is rotated relative to the connector 35, locking the end portion to the connector 35. Disconnection of the connecting device 36 from the connector 35 is performed by reversing these steps. 
     The opposite end portion 43 of the connecting device 36 is shown as being similar to the end portions 11, 12 of the connecting devices 8, 9 previously described in FIGS. 1-9, for interacting with a connector such as the connector 18 as shown in FIG. 10. In such case, the end portion 43 as shown in FIG. 12A is bent relative to the body of the connecting device 36 to effectively mate with its associated connector. The end portion 42 is not bent relative to the body of the connecting device 36, to effectively mate with the clasp 40 of the connector 35 as previously described. The end portion 43 may also be keyed, if desired, to prevent the connecting device 36 from swivelling relative to the connector which receives it. Other variations of the end portion 43 are also possible, to meet the needs of a particular treatment. 
     It will therefore be understood that various changes in the details, materials and arrangement of parts which have been herein described and illustrated in order to explain the nature of this invention may be made by those skilled in the art within the principle and scope of the invention as expressed in the following claims.