Orthodontic treatment including a wire-driven phase and an aligner phase

Abstract

The method includes a wire drive step in which a plurality of appliances are bonded to the teeth, the appliances including a wire retention area and an engagement area. The engagement area has a shoulder configured to releasably engage a corresponding recess in an aligner tray. An archwire is inserted into the wire retention area to move a first maloccluded tooth from a first position to a second position. The wire drive step is followed by an aligner step in which the archwire is removed and an aligner tray is applied over the patient's teeth. The aligner tray includes a cavity shaped to receive the first maloccluded tooth and to resiliently position the first maloccluded tooth from the second position to a third position, and further includes a recess configured to releasably engage at least a portion of the appliances' engagement area.

Description

[Background technology]

[0001] Traditional fixed orthodontic appliances utilize brackets fixed to the patient's teeth with wires engaged by slots in the brackets to apply a force to the teeth to move at least one tooth from a first maloccluded position to a desired finished position. In the early stages of treatment where significant movement of the teeth may be required, the magnitude and direction of the force applied to the teeth can be set by placing brackets on the labial or lingual surfaces of the teeth and inserting superelastic wires into the slots in the brackets to transmit a relatively continuous movement force.

[0002] Although brackets and wires are very effective in producing a wide variety of tooth movements, for aesthetic reasons, patients often prefer aligner trays that can be placed over the teeth. Aligner trays can be made of transparent materials that are difficult to see during treatment and can be inserted and removed from the oral cavity as needed. Aligner trays take advantage of the elastic properties of polymeric materials and precisely shaped tooth-retaining cavities to reposition the teeth, and each aligner tray in a series can be used to gradually move the teeth a relatively short distance compared to the movements possible with brackets and wires. Aligner trays are also mechanically limited to specific movements of the teeth and therefore do not have the versatility of brackets and wires, especially in the early stages of treatment where a wider range of tooth movements may be required. In the first phase of orthodontic treatment, more aligner stages may be required to eliminate the most severe malocclusions. The smaller tooth movements per stage and more precisely defined tooth repositioning make aligner trays particularly well suited to complete the final stages of orthodontic treatment. Summary of the Invention

[0003] Generally, the present disclosure relates to orthodontic treatment systems and methods that utilize an initial wire-driven treatment phase in which appliances are secured to the teeth. The appliances include an interface portion that interfaces with the labial or lingual surface of the teeth, and a wire-retaining region that is configured to retain an archwire, such as an elastic wire, to effect larger and more complex tooth movements that may be required to effectively complete the initial treatment phase in which the teeth are moved from an initial position to a second position. The initial treatment phase is followed by a subsequent or final aligner treatment phase in which the archwire is removed from the appliances and a series of aligner trays are applied over the teeth to move at least one tooth from a second position to a third position. The aligner trays include a number of precisely shaped cavities to receive and resiliently position the teeth, and further incorporate an array of recesses or notches that are configured to releasably engage engagement regions of the exposed surfaces of the appliances. In some cases, the smaller tooth movements and more precisely defined tooth repositioning make the aligner trays particularly well suited to complete the final stages of orthodontic treatment. In some embodiments, the fixtures may optionally be reused for additional wire-driven stages following the aligner stage, or may be removed from the teeth so that a second set of aligner trays can be used to fine-tune or maintain the alignment of one or more teeth.

[0004] The disclosed systems and methods utilize two different tooth alignment tools with different capacities and strengths, potentially providing a faster and more aesthetic orthodontic treatment. The same appliances bonded to the teeth are used for both the wire-driven and aligner phases of treatment. In the wire-driven phase, the appliances receive elastic wires, and in the aligner phase, the appliances engage the aligner trays to facilitate a greater range of tooth movement than would be possible with the aligner trays alone.

[0005] In one aspect, the present disclosure relates to a method for repositioning a first maloccluded tooth of a patient, the method including a wire-driving step including providing a plurality of appliances, each having a wire-retaining region and an engagement region, the engagement region having a shoulder configured to releasably engage a corresponding recess of an aligner tray, bonding each appliance of the plurality of appliances to the patient's teeth, and inserting an archwire into the wire-retaining region of the appliance to move the first maloccluded tooth from a first position to a second position different from the first position. The wire-driving step is followed by an aligner step including removing the archwire from the wire-retaining region of the plurality of appliances, and applying an aligner tray over the patient's teeth, the aligner tray including a plurality of cavities shaped to receive the first maloccluded tooth and to resiliently position the first maloccluded tooth from the second position to a third position different from the second position. The aligner tray further includes an array of recesses configured to releasably engage at least a portion of the engagement region of the fixture.

[0006] In another aspect, the present disclosure relates to an orthodontic treatment system including a plurality of appliances, each appliance including a body with a first end having an interface portion configured to be interfaced to a surface of a patient's tooth and a second end opposite the first end, the second end including a receiver configured to hold an archwire, an outer surface of the receiver having an engagement region with a shoulder; a plurality of archwires insertable into wire retaining hooks of the appliances; and at least one aligner tray, each aligner tray including a plurality of cavities shaped to receive and resiliently position at least one tooth of the patient, the aligner tray further including at least one recess configured to releasably engage with the shoulder of the engagement region of at least one appliance of the plurality of appliances.

[0007] In another aspect, the disclosure provides an orthodontic treatment system including a computer with instructions that, when executed, cause the computer to receive an initial position of at least one tooth of a patient in a treatment plan, receive a final position of at least one tooth in the treatment plan, and determine a movement geometry including movement of the at least one tooth between the initial and final positions, the treatment plan comprising: a wire-driving step of bonding a plurality of appliances to at least a first portion of the patient's teeth, each appliance of the plurality of appliances including a body having a first end having an interface portion configured to be bonded to a surface of the tooth and a second end opposite the first end, the second end including a wire retention region and an engagement region with a shoulder and an undercut region configured to releasably engage a corresponding recess in an aligner tray; and an aligner step following the wire driving step, the aligner step including removing the archwire from the wire retaining areas of the plurality of appliances and applying an aligner tray over at least a portion of the patient's teeth, the aligner tray including a plurality of cavities shaped to receive the at least one tooth of the first portion of the patient's teeth in accordance with the treatment plan and to resiliently position the at least one tooth from the second position to a third position different from the second position, the aligner tray further including an array of recesses configured to releasably engage at least a portion of a shoulder and an undercut area of ​​the engagement area of ​​the appliance.

[0008] In another aspect, the present disclosure relates to an attachment device for orthodontic treatment, the attachment device including a body having a first end including an interface portion configured to be bonded to a tooth surface, and a second end opposite the first end, the second end having a wire retaining groove and an outer surface including an engagement region, the engagement region having a shoulder configured to releasably engage a corresponding recess in an aligner tray.

[0009] The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will become apparent from the description and drawings, and from the claims. [Brief description of the drawings]

[0010] [Figure 1A] 1 is a schematic perspective view of an embodiment of a bracket bonded to a tooth surface in accordance with the present disclosure; FIG. [Figure 1B] FIG. 13 is a schematic perspective view of an overhead view of another embodiment of a bracket bonded to a tooth surface. [Figure 2A] FIG. 1 is a schematic cross-sectional view of an embodiment of an orthodontic system including appliances bonded to surfaces of the teeth and an aligner tray covering the teeth and releasably attached to the appliances. [Figure 2B] FIG. 2 is a schematic cross-sectional view of another embodiment of an orthodontic system including appliances bonded to surfaces of the teeth and an aligner tray covering the teeth and releasably attached to the appliances. [Diagram 3] 1 is a flow chart of a method for orthodontic treatment according to the present disclosure. [Figure 4A] FIG. 1 is a schematic perspective view of an orthodontic system including appliances and an archwire configured for vertical movement of the teeth. [Figure 4B] FIG. 1 is a schematic perspective view of an orthodontic system including appliances and an archwire configured for vertical movement of the teeth. [Figure 5A] FIG. 1 is a schematic perspective view of an orthodontic system including appliances and an archwire configured for horizontal movement of teeth. [Figure 5B] FIG. 1 is a schematic perspective view of a fixture with a wire retention area configured to apply forces to teeth in various directions. [Figure 5C] 1 is a flow chart of an embodiment of a process for selecting appropriate appliances for the wire-driven phase of orthodontic treatment. [Figure 6] FIG. 5C is a schematic perspective view showing engagement of the fixture of FIG. 5B with a recess in a portion of an aligner tray. [Figure 7] FIG. 1 is a schematic perspective view of an embodiment of an orthodontic system including appliances and an archwire configured for angulation of the teeth. [Figure 8A] FIG. 8A is a schematic overhead view and FIG. 8B is a schematic perspective view of an orthodontic system including appliances and an archwire configured to rotate the teeth. [Figure 8B] FIG. 8A is a schematic overhead view and FIG. 8B is a schematic perspective view of an orthodontic system including appliances and an archwire configured to rotate the teeth. [Figure 9A] FIG. 1 is a schematic perspective view of an embodiment of an orthodontic system including basic appliances and an archwire. [Figure 9B] FIG. 9B is a side view of the appliance of the orthodontic system of FIG. 9A. [Figure 9C] FIG. 9B is a side view of the appliance of the orthodontic system of FIG. 9A. [Figure 10A] FIG. 1 is a schematic perspective view of an appliance of the present disclosure bonded to a lingual surface of a tooth. [Figure 10B] 10B is a schematic perspective view of the fixture of FIG. 10A showing the direction of force applied to the teeth by the fixture of FIG. 10A.

[0011] Like numbers in the drawings indicate like elements. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] 1A, a schematic diagram (not to scale) of a fitting article 10 includes a body 12 with a first end 13 having an interface portion 14. Interface portion 14 is shaped to conform to and interface with an exposed labial or lingual surface 16 of a tooth 20. In various embodiments, interface portion 14 may include an interface area that is shaped, contoured, or otherwise configured for attachment to a particular surface 16 or portion thereof.

[0013] Body 12 further includes a second end 21 with a groove 26 having an inner surface 24 configured to retain an archwire (not shown in FIG. 1A). Groove 26 has a cross-sectional shape configured to retain a selected archwire, with typical cross-sectional shapes including, but not limited to, circular, square, rectangular, arcuate (e.g., C-shaped or U-shaped), and the like, including combinations of linear and arcuate elements (e.g., J-shaped, D-shaped, or V-shaped).

[0014] In some embodiments, the body 12 includes a receiver 22 that can be used to securely retain an archwire within the slot 26, and in some embodiments the receiver 22 may be deflected to allow for insertion or removal of an archwire into or from the slot 26. The receiver 22 extends toward the first end 13 of the body 12 and includes an optional flap-like retention region 28 that at least partially overlaps the slot 26 to further enhance retention of the archwire within the slot 26.

[0015] In some embodiments, the body 12 of the fitting article 10 further includes an optional spacer portion 30 that extends away from the interface portion 14 and is shaped to extend the groove 26 a predetermined distance from the tooth surface 16. In some embodiments, the shape and dimensions of the spacer portion 30 are configured to allow for wire insertion and to maintain retention of the archwire after it is inserted into the groove 26. However, in some cases, as shown in more detail below, the body 12 can be designed with minimal or even no spacer portion 30 to allow the archwire to reside closer to or against the surface 16 of the tooth 20. Additionally, in some instances, the body 12 can include a support region 32 underlying the receiver 22 and the groove 26, the support region 32 having an outer surface configured to rest against or engage an aligner tray (not shown in FIG. 1A). In some embodiments, the slope of the support region 32 may be configured to make removal of the aligner tray easier.

[0016] The receiver 22 of the attachment article 10 includes an external engagement surface 40 exposed on the distal side of the tooth surface 16 and an interface portion 14 configured to releasably engage an appropriately shaped recess in an aligner tray (not shown in FIG. 1A). The shape of the corresponding recess in the aligner tray may vary widely and in various exemplary embodiments may include a slot, an opening, a protrusion, a bubble, an envelope, an annulus, a wedge, a prism, or combinations thereof. The shape of the engagement surface 40 may vary widely to match the recess or arrangement of recesses in the aligner tray, but in the embodiment of FIG. 1A includes a rounded shoulder 42, a planar portion 44 generally parallel to the interface portion 14, and an undercut region 46. In some instances, as discussed above, the support region 32 may also have an engagement surface 33 for further retaining the alignment tray.

[0017] In various embodiments, the attachment article 10 is made from metal, ceramic, polymeric materials, and the like. In some examples, all or part of the article 10 may be directly three-dimensionally (3D) printed from a polymeric material, a polymer-metal composite, or a polymer-ceramic composite using SLM, SLA, or DLP vat printing methods, or precision binder jetting, or may be 3-axis or 5-axis milled from any of these materials. In some embodiments, the polymeric material, metal, ceramic, or composite of these has relatively elastic properties so that the receiver 22 can bend and flex to facilitate the introduction of the archwire, and return to a fixed position once the archwire is seated in the groove 26. However, the material used to form the attachment article 10 does not need to be elastic, and the flexibility of the archwire itself may be sufficient to allow insertion and retention or self-ligation.

[0018] The interface portion 14 of the attachment article 10 may have any suitable shape and size depending on the intended use of the attachment article 10, and may be made larger or smaller as necessary to facilitate secure attachment to the surface 16 of the tooth 20. The attachment article 10 may be bonded to the surface 16 of the tooth 20 using any suitable orthodontic adhesive, examples include, but are not limited to, epoxies, (meth)acrylate adhesives, and the like, where (meth)acrylates include acrylates and methacrylates. In some examples, the body 12 of the attachment article may include a limited selection of standardized basic designs that are mass-produced, and the interface portion 14 may be individually configured to directly fit a particular tooth to the standardized body 12, for example, by processes such as milling, laser machining, 3D printing, and the like.

[0019] 1B, in another embodiment, a fitting article 100 includes a body 112 with a first end 113 having an interface portion 114 that is interfaced to a surface 116 of a tooth 120. The body 112 includes a spacer portion 130 that extends away from the tooth surface 116. The body 112 further includes a second end 121 that includes a receiver 122. The receiver 122 has an inner surface 124 that defines a groove 126 configured to hold an archwire (not shown in FIG. 1B). The groove 126 has a cross-sectional shape configured to hold an archwire having a corresponding cross-sectional shape, and in the embodiment of FIG. 1B includes a recessed area 127 configured to facilitate introduction or removal of the archwire. The receiver 122 includes an overhanging retention area 128 that extends toward the first end 113 of the body 112 and partially overlaps the groove 126.

[0020] The receiver 122 has an exterior engagement surface 140 exposed distally of the tooth surface 116 and interface 114. The engagement surface 140 is configured so that at least a portion of the engagement surface 140 releasably engages an appropriately shaped recess in a polymeric aligner tray (not shown in FIG. 1B). In the embodiment of FIG. 1A, the engagement surface 140 includes a rounded shoulder 142, a planar portion 144 generally parallel to the interface 114 and tooth surface 116, and an undercut region 146.

[0021] Referring now to the structure 200 of FIG. 2A, the attachment article 210 includes a body 212 with a first end 213 having an interface portion 214 that is interfaced to a surface 216 of a tooth 220. The body 212 further includes a second end 221 with a receiver 222. The receiver 222 has an inner surface 224 that defines a generally J-shaped groove 226 configured to engage and retain an appropriately shaped archwire (not shown in FIG. 2A). The receiver 222 includes a retention region 228 that extends toward the first end 213 of the body 212 and at least partially overlaps the groove 226 to further enhance retention of the archwire within the groove 226. The body 212 includes a minimal spacer portion 230 and a support region 232 underlying the receiver 222.

[0022] The aligner tray 250 includes cavities 254 shaped to fit over the crowns 256 of the teeth 220 and to engage opposing surfaces 216, 217 of the teeth 220. The aligner tray further includes a wall 251 including recesses (i.e., receivers) 252 shaped to extend away from the surfaces 216 of the teeth 220 and to releasably engage at least a portion of the exposed outer engagement surface 240 of the attachment article 210.

[0023] In various embodiments, the aligner tray 250 may be made from a wide variety of materials, including metals, ceramics, polymers, and mixtures and combinations thereof. The aligner tray 250 may be formed using a wide variety of techniques, including, but not limited to, molding, 3D printing, thermoforming, laser patterning, microreplication, etc. Suitable materials and methods for making aligner trays are discussed, for example, in co-owned U.S. Application No. 63 / 091113, filed October 13, 2020.

[0024] In one embodiment, a suitable configuration of tooth (or teeth) retaining cavity is formed into a substantially flat sheet of a single layer polymer film or a multi-layer polymer film comprising multiple layers of polymeric materials. In some embodiments, the polymer film may be formed into a dispersion and cast into a film or applied onto a mold having a tooth receiving cavity. In some embodiments, the polymer film may be prepared by extruding the polymer layer material through a suitable die to form a film. In some embodiments, a reactive extrusion process may be used in which one or more polymer reaction products are charged into an extruder to form one or more layers during the extrusion procedure. In yet other embodiments, the polymer film may be deposited onto the mold by chemical vapor deposition, as described in U.S. Provisional Application No. 62 / 736,774, filed September 26, 2019, and entitled "Parylene Dental Articles."

[0025] In some embodiments, the polymer film may later be thermoformed into a dental appliance having a tooth-retaining cavity, or may be injected into a mold containing a tooth-retaining cavity, or may be manufactured using a three-dimensional (3D) printing process. The tooth-retaining cavity may be formed by any suitable technique, including thermoforming, laser processing, chemical or physical etching, and combinations thereof, but thermoforming has been found to provide good results and excellent efficiency. In some embodiments, the polymer film is heated before forming the tooth-retaining cavity, or its surface may be optionally chemically treated, such as by etching, or mechanically embossed by contacting the surface with a tool, before or after forming the cavity.

[0026] The polymer film, the formed dental appliance, or both, may optionally be crosslinked with radiation selected from electron beam, gamma radiation, UV, and mixtures and combinations thereof.

[0027] At least a portion of the engagement surface 240 of the attachment article 210 is configured to releasably engage the recess 252 and includes a rounded shoulder 242, a flat portion 244 that is generally parallel to the interface portion 214, and an undercut region 246. In the embodiment of FIG. 2A, the wall 251 of the polymeric aligner tray 250 further includes an undercut region 260 that extends around the engagement surface 240 and is shaped to fit against the surface 216 of the tooth 220 in the area below the attachment article 210.

[0028] In another embodiment, shown in Figure 2B, a structure 300 includes an attachment article 310 with a body 312 attached to a surface 316 of a tooth 320 via an interface portion 314. The body 312 further includes a receiver 322 having an inner surface 324 forming a generally J-shaped groove 326 configured to retain an archwire (not shown in Figure 2B). The receiver 322 includes a retention region 328 that partially overlies the groove 326. The body 312 further includes a spacer portion 330 and a support region 332 underlying the receiver 322.

[0029] The polymeric aligner tray 350 includes cavities 354 shaped to fit over the crowns 356 of the teeth 320 and to engage opposing surfaces 316, 317 of the teeth 320. The polymeric aligner tray further includes a wall 351 including a protruding recess 352 shaped to releasably engage the exposed outer engaging surface 340 of the attachment article 310.

[0030] At least a portion of the engagement surface 340 is configured to releasably engage the recess 352 and includes a rounded shoulder 342, a planar portion 344 generally parallel to the interface portion 314, and an undercut area 346. In the embodiment of Figure 2B, the wall 351 of the polymeric aligner tray 350 has a reduced undercut area compared to the embodiment of Figure 2A, where the undercut area is shaped to fit around the engagement surface 340 and to engage the surface 316 of the tooth 320 in the area below the attachment article 310, and extends only a portion of the distance between the occlusal portion of the tooth and the gum line (not shown in Figure 2B). Instead, the polymeric aligner tray 350 includes a tab 370 extending downwardly from the recess 352 that does not contact the tooth surface 316. In some orthodontic treatments, the recesses 352 including the tabs 370 may fit less snugly around the engagement surface 340 of the attachment device 310 to provide a pathway making attachment and removal of the polymer aligner tray 350 easier and more comfortable for the patient. In another exemplary embodiment, the tabs 370 may be configured to angle or slope toward the tooth surfaces 316 to avoid potential tongue sores. In yet another embodiment, the tabs 370 may simply be omitted, leaving a slight protrusion of tray material that protrudes at least somewhat horizontally in the undercut area.

[0031] The attachment device and polymeric aligner tray shown in Figures 1A-1B and 2A-2B are particularly well suited for use in an orthodontic method for repositioning at least one tooth of a patient using multiple types of orthodontic appliances. The method includes a wire-actuating step in which the appliances are bonded to at least one of the lingual and labial surfaces of the teeth. A resilient archwire is inserted into the wire-retaining slots of the appliances to move at least one tooth of a first portion of the teeth from a first position to a second position different from the first position.

[0032] The method further includes an aligner stage, which may be performed before or after the wire-driving stage in various embodiments. In the aligner stage, the archwire is absent from the wire-retaining area of ​​the appliances, and an aligner tray is utilized to further reposition the patient's teeth. The aligner tray includes a plurality of cavities shaped to receive at least one tooth of a first portion of the patient's teeth and to resiliently position the at least one tooth from a second position to a third position different from the second position. The aligner tray further includes an array of recesses configured to releasably engage at least a portion of the engagement area of ​​the appliances.

[0033] In some embodiments, the method further includes a second wire-driven stage following the aligner stage, which utilizes appliances bonded to the teeth and may utilize the same or a different archwire to effectively move the teeth from the third position to the fourth position.

[0034] In some embodiments, following the aligner stage, the fixtures may be removed and the aligner tray may be used without the fixtures to move the teeth from the third position to the fourth position to provide finer finishing adjustments to the teeth.

[0035] In some embodiments, the method includes an initial aligner stage followed by a wire drive stage. The subsequent wire drive stage can be followed by one or more aligner or wire drive stages.

[0036] Splitting the orthodontic treatment process into at least two separate stages can have several advantages. Teeth suffer from interproximal interferences between teeth that can impede tooth movement, especially if they are clogged. For aligner trays to be effective, accurate 3D scan data should be used to create realistic models of the teeth. The areas of the teeth that are most difficult to model accurately are the interproximals, which are also the areas most prone to interference. Intraoral scanners can have difficulty imaging these areas, and physical impression materials may not be able to penetrate the narrowest areas between teeth. Triangular meshing software may not be able to properly identify the interproximal surfaces, due to points on neighboring teeth being confused with points on the target tooth. Interproximal mesh data may be removed and regenerated by a parametric model in a subsequent processing step. The interproximal data used to predict where the teeth will intersect during the staged tooth movement may be slightly inaccurate, and thus the prescribed movement may be mechanically impeded, if not impossible, due to tooth collisions that result in excessive friction or interference. Because polymer aligner trays define tooth movement very precisely, leaving no undefined degrees of freedom, if the teeth collide, reaction forces that would have caused the teeth to change direction and deviate from the defined path are restrained by the aligner material which completely surrounds the teeth.

[0037] In contrast, the appliances and archwire provide at least one degree of freedom that remains undefined: mesiodistal movement as a result of the sliding action, as well as "slop" between the wire and bracket, and bowing of the wire, especially when flexible wires are used. Because the archwire can slide along the appliance channel, i.e., the attachment slot, the tooth is free to move in the mesiodistal direction when a force is applied in any other direction that includes a significant mesiodistal vector component. For example, a force vector at a 45° angle to the tooth can be resolved into labial and distal vector components, each of approximately equal magnitude. If a tooth is placed somewhat toward the lingual side of its mesial neighbor, it may be prevented from moving labially at its mesial edge by the interfering tooth, but if it does not contact the distal neighbor, it can slide freely distally along the archwire until the interference with its mesial neighbor is eliminated. When this happens, the tooth is free to express labially movement with the labial vector component of the force vector. With traditional aligner trays, such freedom is not possible because the trays surround the teeth on all sides.

[0038] By treating with appliances and archwires in the early stages of treatment, the sliding action can be used to automatically eliminate collisions between teeth in the interproximal areas without the need to precisely prescribe their movement. This can be done more quickly than treatment with aligner trays alone, because the force exerted by the archwire is relatively continuous and the movement is less impeded by allowing more degrees of freedom.

[0039] One advantage of using fixed orthodontic appliances in the wire-driven phase is that the risk of patient non-compliance is reduced since the patient cannot remove the appliances during treatment. The amount of control required to achieve early tooth movement in the wire-driven phase can be set by adjusting the slotted wire system. For example, the placement of the appliances on all or a portion of the teeth can be influenced by the elastic properties of the archwire. For example, in some embodiments, an archwire with a rectangular cross-sectional shape and a corresponding rectangular wire-retaining area of ​​the appliances on the teeth provides the greatest degree of control. In some cases, especially when using nickel-titanium and copper-nickel-titanium wires, the archwire can transmit a relatively continuous force, which is very helpful in moving teeth in the early stages of treatment where large movements are often required. In contrast, the force applied by an aligner tray may decrease more rapidly as the teeth begin to move. Thus, wires tend to have a longer range of expression compared to aligner trays.

[0040] A typical malocclusion that would benefit from a wire-driven stage is a crowded front tooth, which may take a long time to resolve with aligners, but has rapid progress when treated with appliances and archwires for the reasons outlined above. Because the aligner tray is pushing against the crowns of the teeth embedded in the jawbone, it tends to tilt the crowns of the teeth into space rather than keeping them upright, and in some instances the appliance and wire system can better move the crowns without this undesirable side effect.

[0041] Because the wire provides a track along which the brackets can slide, and the driving force is typically an elastic chain that connects the brackets and pulls them together, the engagement between the bracket slots and the archwire limits the opportunity for the crowns of the teeth to tip into space. In another example, eliminating a curve of Spee by pushing out a bicuspid may be more effective with a bracket-and-wire system due to the difficulty of gripping the tooth with the cavity of an aligner tray. Rotating rounded teeth such as bicuspids and canines can also be tricky with aligners and may benefit from a bracket-and-wire approach.

[0042] In some embodiments, when a custom-bent (or otherwise custom-fabricated) archwire is used in the first wire-driven phase of treatment, there is an opportunity to more strategically position the appliances to be attached, taking into account not only the positions that would be convenient for achieving the wire-driven phase movements, but also the movements prescribed for the other phases of treatment using the tray engagement mechanism and aligner trays. For example, the most convenient appliance attachment site on the teeth for the appliance and wire phase may be the facial axis point (FA point), but to improve engagement of the clear aligner to the teeth in the aligner phase, the appliance may be better placed 1-2 mm gingivally of the FA point, taking into account the prescribed tooth movements, the lack of features in the natural tooth anatomy, and the attachment points on the teeth. In such cases, if modifying the appliance position would not have a detrimental effect, a compromised position may be used in the wire-driven phase, and a custom archwire designed to engage the appliances at this other position can be fabricated. The appliances would then be better positioned for the aligner phase, when the archwire is removed and the clear aligner is placed on the teeth.

[0043] In some cases, the fixtures can also be placed on the lingual surfaces of the teeth, making the wire-driven stage more aesthetic for the patient. However, in other cases, the fixtures are on the labial surfaces of the teeth and therefore visible. For this reason, patients tend to prefer aligner trays for aesthetic and easier dental hygiene reasons, and are motivated to switch to aligners as soon as difficult tooth movements that may be hindered by collisions are achieved. Since the aligners are almost invisible and patients can decide for themselves when to have them in their mouth and when not, aligners are considered to be less painful and more lifestyle-type appliances. Aligner trays can only bring about minor tooth movements per stage and may be mechanically limited to certain tooth movements. Smaller tooth movements per stage and precisely defined tooth positions and orientations are good prerequisites for good finishing capabilities. In some embodiments, aligner trays can be used for smaller finishing tooth movements after the larger tooth movements by the wire-driven stage are completed.

[0044] The orthodontic treatment method of the present disclosure provides two appliance types as two different tools with different capabilities and strengths, resulting in the possibility of faster and more aesthetic patient treatment. It is desirable that the same appliances used to move the teeth in the first treatment phase using fixtures and wires can also be used to assist in moving the teeth in the second treatment phase by providing improved engagement of the aligner trays with the teeth.

[0045] 3 is a flow chart showing steps of a method 360, such as a computer-implemented method, for providing sequential wire-driven treatment and aligner phases. In step 362, the method includes determining first and second positions of the teeth, which may be determined by suitable imaging techniques, such as 3D scanning, CT scanning, etc., as described above. Then, in step 364, the type of appliance for each tooth and the appliance position for each tooth are determined, either manually or digitally, to provide a movement path from the first position to the second position. In step 366, an archwire or series of appliances are selected and inserted into the appliances to move the teeth from the first position to the second position.

[0046] In step 368, a series of aligner trays are digitally designed and fabricated that include one or more cavities configured with a volume or shape to accommodate smaller or finish movements of the teeth to which the appliances are bonded from the second position to the third position after or after the larger movements of the teeth are substantially completed in step 366. In step 370, the archwire is removed from the appliances and each of the series of aligner trays is applied over the patient's teeth to gradually move the teeth from the second position to the third position.

[0047] In step 372, following the aligner stage described in steps 368-370, an optional additional stage is where a second archwire, which may be the same or different from the first archwire, is inserted into the appliances for further movement of the teeth. In some examples, the wire drive stage including the second archwire may be followed by an optional alignment tray or a series of additional aligner trays with cavities configured to move the teeth from the second position to a third position.

[0048] In step 374, another optional step following the aligner step of steps 368-370, the fixtures are removed from the teeth and a second series of aligner trays is designed with cavities configured to move the teeth from the second position to a third position or to maintain alignment of the teeth in the third position.

[0049] In some examples, a dental treatment system according to the present disclosure is provided to a dentist in the form of a kit that includes a series of fixtures having different shapes configured to effect different types of tooth movement (further details are provided below), an archwire, an orthodontic aligner tray, and instructions for patient use. Additional items suitable for the kit, which are not intended to be limiting, include one or more of the following: a carry case, a removal tool to help the patient remove the aligners from the teeth, a fastening tool to help press the aligners onto the teeth, a toothbrush, aligner tray cleaning tablets, powder / crystals, or gel / foam / liquid, abrasive paper or objects to address discomfort from sharp edges or corners of the dental appliances, whitening gel or pen, dental floss, dental picks, wax, etc.

[0050] A wide variety of different fixture designs may be used to achieve specific tooth movements in the above methods, and some non-limiting examples are presented and discussed below.

[0051] 4A, there is shown a configuration 400 of attachment articles 410A, 410B, and 410C that can be used to effect vertical movement (along occlusal axis O) of teeth in a patient's mouth. In the configuration 400, attachment article 410A is bonded to a surface 416A of a first tooth 420A, and attachment article 410C is bonded to a surface 416C of a third tooth 420C. Attachment article 410B is bonded to a surface 416B of a second tooth 420B between teeth 420A and 420C. The second tooth 420B extends above a plane that contains teeth 420A, 420C.

[0052] The attachment articles 410A, 410C include bodies 412A, 412C each having an interface portion 414A, 414C attached to a respective tooth surface 416A, 416C. The bodies 412A, 412C further include spacer portions 430A, 430C extending away from the tooth surface 416A, 416C. The spacer portions 430A, 430C include substantially planar portions 431A, 431C that are substantially perpendicular to the tooth surface 416A, 416C. The planar portions 431A, 431C extend to downward receivers 422A, 422C. The receivers 422A, 422C each have an inner surface 424A, 424C that form a generally J-shaped groove 426A, 426C configured to hold an archwire 480.

[0053] The outer surfaces of the receivers 422A, 422C have exposed external engagement surfaces 440A, 440C configured to releasably engage appropriately shaped recesses in an aligner tray (not shown in FIG. 4A). The engagement surfaces 440A, 440C include rounded shoulders 442A, 442C and undercut regions 446A, 446C, respectively, which form a roof-like shape that can releasably engage the recesses in the aligner tray.

[0054] The attachment article 410B includes a body 412B with an interface portion 414B attached to a tooth surface 416B. The body 412B further includes a spacer portion 430B extending outwardly from the tooth surface 416B. The spacer portion 430B includes a substantially planar portion 431B that is substantially perpendicular to the tooth surface 416B. A wall 435B extends generally perpendicular to the planar portion 431B and substantially parallel to the tooth surface 416B. The wall 435B forms an upwardly facing receiver 422B. The receiver 422B forms a generally J-shaped groove 426B configured to hold an archwire 480.

[0055] The outer surface of the receiver 422B has an exposed outer engagement surface 440B configured to releasably engage an appropriately shaped recess in an aligner tray (not shown in FIG. 4A). The engagement surface 440B includes a rounded shoulder 442B and an undercut region 446B, which form a roof-like shape that can releasably engage the recess in the aligner tray.

[0056] As shown diagrammatically in FIGURE 4B, the upward receivers 422A, 422C hold an archwire 480, which exerts a force against the groove 426B of the downward receiver 422B in a direction generally parallel to the tooth surface 416B (the occlusal direction). The constant downward force exerted by the resilient archwire 480 against the groove 426B gradually moves the tooth 420B vertically downward into alignment with the adjacent teeth 420A, 420C. As the tooth 420B moves downward, the grooves 426A, 426C of the receivers 422A, 422C hold the archwire 480 in proper relationship against the surfaces of the teeth 416A-C, and the malpositioned teeth are used to hold the archwire 480.

[0057] In some embodiments, the central fixture 410B can optionally be positioned higher on the surface 416B as an overcorrection to ensure better engagement of the archwire 480 within the groove 426B of the receiver 422B and to maintain retention of the archwire even when the tooth 420B is in its intended position. In some examples, the fixture 410B can be positioned such that the force applied to the tooth 420B is below the threshold required to move the tooth further and such that the fixture 410B retains the archwire.

[0058] 5A, in another embodiment, a configuration 500 of attachment articles 510A, 510B, and 510C is shown that may have a shape and groove configuration suitable for moving teeth along a horizontal direction (along a lingual axis L) in a patient's mouth. In the configuration 500, attachment article 510A is bonded to a surface 516A of a first tooth 520A, and attachment article 510C is bonded to a surface 516C of a third tooth 520C. Attachment article 510B is bonded to a surface 516B of a second tooth 520B between teeth 520A and 520C. The second tooth 520B generally extends behind a plane that includes teeth 520A, 520C.

[0059] The attachment articles 510A, 510C include bodies 512A, 512C each having an interface portion 514A, 514C attached to a respective tooth surface 516A, 516C. The bodies 512A, 512C further include spacer portions 530A, 530C extending outwardly from the tooth surfaces 516A, 516C. The spacer portions 530A, 530C include substantially planar portions 531A, 531C that are substantially perpendicular to the tooth surfaces 516A, 516C. The planar portions 531A, 531C extend to downward receivers 522A, 522C. The bodies 512A, 512C further include generally upward receivers 523A, 523C.

[0060] The upward receivers 522A, 522C and downward receivers 523A, 523C define inner surfaces 524A, 524C that form a generally C-shaped groove 526A, 526C configured to retain the archwire 580.

[0061] The outer surfaces of the receivers 522A, 522C, 523A, 523C have exposed external engagement surfaces 540A, 540C configured to releasably engage appropriately shaped recess structures in an aligner tray (not shown in FIG. 4A). The engagement surfaces 540A, 540C include rounded shoulders 542A, 542C and undercut regions 546A, 546C.

[0062] The attachment article 510B includes a body 512B with an interface portion 514B attached to a tooth surface 516B of a tooth 520B. The body 512B further includes a spacer portion 530B extending outwardly from the tooth surface 516B. The spacer portion 530B includes a substantially planar portion 531B that is substantially perpendicular to the tooth surface 516B. A wall 535B extends generally perpendicular to the planar portion 531B and substantially parallel to the tooth surface 516B. The wall 535B forms a surface 524B that extends to an upward receiver 522B. The receiver 522B forms a generally J-shaped groove 526B configured to retain an archwire 580 and to apply a force to the tooth 520B along a lingual direction.

[0063] The outer surface of the receiver 522B has an exposed outer engagement surface 540B configured to releasably engage an appropriately shaped recess structure in an aligner tray (not shown in FIG. 5A). The engagement surface 540B includes a rounded shoulder 542B and an undercut region 546B.

[0064] The J-shaped groove 526B in receiver 522B grips wire 580 like a hand grips a bucket handle. The grooves 526A, 526C in the distal and mesial fixtures 510A, 510C relative to the central fixture 510B face lingually, and wire 580 is held in grooves 526A-C by force applied to archwire 580 in the direction opposite the groove opening.

[0065] FIG. 5B shows some examples of various different appliance designs and the principal force vectors they may apply to the teeth. For example, appliance design 550 is configured to push / extend the teeth along occlusal direction A. Appliance 552 is inverted relative to appliance 550 and therefore presses the teeth along occlusal direction B opposite occlusal direction A. Appliance design 554 includes an explicit receiver that may move the tooth along lingual direction C (or opposite C if bonded to the labial side of the tooth). Appliance 556 includes a slot through which a wire may apply force to move the tooth in labial direction D. For example, a tubular receiver design 558 may be used to hold a wire to a tooth distal to the tooth (or teeth) being moved by the archwire. Depending on the malocclusion and the inter-appliance distance, in some embodiments, multiple consecutive appliances 558 may be used to hold a superelastic round archwire such as, for example, 0.014 round NiTi.

[0066] In various embodiments, the fixtures 550-558 can be selected manually or with the aid of software after evaluating how a particular tooth needs to be moved from a first position of malocclusion to a second position of less malocclusion. In the digital set-up software used to plan the orthodontic treatment, the malocclusion-to-set-up transformation matrix is ​​known for all teeth. From this matrix, the resulting movement vectors can be defined. Based on these data, the software can select the fixture from above that best represents the movement vector. For example, if primarily lingual tooth movement is desired, the software can first select fixture 554 of FIG. 5B. In some instances, the software can also be used to simulate wire bowing and incorporate the results into the selection of fixtures.

[0067] When utilizing software to determine the precise movement of each tooth, in some embodiments the fixtures of FIG. 5B can also be fine-tuned by rotating them with certain limits about the wire axis.

[0068] 5C, a process 600 includes a treatment planning step 602 of selecting an appliance (including, but not limited to, appliances 550-558 shown in FIG. 5B) and archwire options for use in a wire drive phase of orthodontic treatment planning to at least partially resolve one or more malocclusions of a patient. The treatment planning step 602 includes a transformation matrix forming step 604. A first portion of the transformation matrix, which obtains individual translation and rotation vectors for each tooth to be orthodontally treated, is created in an appliance design step 606, followed by a second portion of selecting in step 608 the appropriate appliance for each tooth depending on the individual translation and rotation vectors from step 606.

[0069] In a setup phase 610, one or more custom archwires are configured in an appliance design phase 612 based on the tooth attachment positions and selected appliances determined in steps 606 and 608. In step 614, the design is verified using finite element analysis (FEA) in step 616 to determine if the wire forces will hold the archwire in all of the appliances throughout the course of patient treatment.

[0070] If the FEA determines that the archwires will be held in the selected fixtures by the wire forces, the design is complete at step 618. If one or more of the archwires may become dislodged from the fixtures during treatment, at step 620, the fixtures may optionally be replaced with a self-ligating fixture design (see, e.g., FIGS. 1-2) that includes receivers and grooves configured to more securely hold the archwires.

[0071] Once the appliances and archwire have been constructed and the appliance positions have been determined for each tooth, the wire-driven phase of orthodontic treatment begins.

[0072] The process of FIG. 5C is not intended to be limiting, but is merely presented as an example of how relatively simple, low-cost appliances such as those shown in FIG. 5B may be combined with selected archwires to complete a wide variety of orthodontic treatments.

[0073] As shown diagrammatically in Figure 6, all of the fixtures 650-658 reproduced by Figure 5B have different wire-retaining groove configurations and are configured to apply forces in different directions against the teeth, but the fixtures have one common basic exterior roof-like geometry that provides a substantially similar or uniform mounting surface 659 for releasably engaging with the recesses 662 of the aligner tray 660. The common mounting surface 659 allows the fixtures 650-658 to be used in the aligner phase of the orthodontic treatment method described above regardless of their individual geometries and groove shapes. The shape of the recesses 662 of the aligner tray 660 can all be the same, but multiple different fixtures can be used to move the teeth along different directions in the patient's mouth.

[0074] 7, an attachment device 700 configuration configured to eliminate tooth angulation includes an attachment article 710A including a body 712A with an interface portion 714A attached to a surface 716A of a tooth 720A. The body 712A includes a downward (i.e., gingival) facing receiver 722A that defines a wire retention groove 726A configured to retain an archwire 780 adjacent the surface 716A of the tooth 720A. An outer surface of the receiver 722A has an exposed outer engagement surface 740A configured to releasably engage an appropriately shaped recess structure of an aligner tray (not shown in FIG. 7). The engagement surface 740A includes a rounded shoulder 742A and an undercut region 746A.

[0075] Similarly, the attachment article 710C includes a body 712C with an interface portion 714C attached to a surface 716C of a tooth 720C. The body 712C includes an upwardly (i.e., occlusally) facing receiver 722C that defines a wire-retaining groove 726C configured to retain an archwire 780 adjacent the tooth surface 716C. An outer surface of the receiver 722C has an exposed outer engagement surface 740C configured to releasably engage an appropriately shaped recess structure in an aligner tray (not shown in FIG. 7). The engagement surface 740C includes a rounded shoulder 742C and an undercut region 746C.

[0076] Tooth 720B includes an attachment article 710B with a first body 711B and a second body 713B. Bodies 711B and 713B are each attached to tooth surface 716B via respective interfaces 714B-1 and 714B-2.

[0077] The first body 711B includes a spacer portion 730B-1 extending outwardly from the tooth surface 716B, with a downward receiver 722B-1 extending along a portion of the length of the spacer portion 730B-1. The receiver 722B-1 forms a generally J-shaped groove 726B-1 configured to hold an archwire 780 adjacent the tooth surface 716B. An outer surface of the receiver 722B-1 has an exposed outer engagement surface 740B-1 configured to releasably engage an appropriately shaped recess in an aligner tray (not shown in FIG. 7). The engagement surface 740B-1 includes a rounded shoulder 742B-1 and an undercut region 746B-1.

[0078] Similarly, the second body 713B includes a spacer portion 730B-2 extending outwardly from the tooth surface 716B, but with an upward receiver 722B-2 extending along a portion of the length of the spacer portion 730B-2. The upward receiver 722B-2 acts in conjunction with the downward receiver 722B-1 of the first body 711B to securely hold the archwire 780 and angle the tooth 720B. The receiver 722B-2 forms a generally J-shaped groove 726B-2 configured to hold the archwire 780 adjacent the tooth surface 716B. In the embodiment of FIG. 7, the groove 726B-2 and the groove 726B-1 can have very similar cross-sectional shapes, but in other examples may have different shapes depending on the intended application.

[0079] The outer surface of the receiver 722B-2 has an exposed outer engagement surface 740B-2 configured to releasably engage an appropriately shaped recess structure in an aligner tray (not shown in FIG. 7). The engagement surface 740B-2 includes a rounded shoulder 742B-2 and an undercut region 746B-2.

[0080] 8A-8B, when a tooth requires rotational correction, a fixture configuration 800 can be used to apply a horizontal force appropriate to create the moment required for rotation. Teeth mesial and distal to the tooth to be rotated also feature fixtures for horizontal movement of the tooth to counter reaction forces. As shown in FIGS. 8A-8B, teeth 820A, 820B, 820C include respective fixture articles 810A, 810B, 810C with bodies 812A, 812B, 812C secured to tooth surfaces 816A, 816B, 816C via interfaces 814A, 814B, 814C.

[0081] The body 812A of the attachment article 810A includes a spacer 830A that forms a downward receiver 822A. The body 812A further forms a groove 826A having a generally C-shaped cross-section configured to hold an archwire 880. The receiver 822A has an exposed exterior engagement surface 840A that is configured to releasably engage an appropriately shaped recess in an aligner tray (not shown in FIGS. 8A-8B). The engagement surface 840A includes a rounded shoulder 842A and an undercut region 846A.

[0082] The body 812C of the attachment article 810C includes a spacer 830C that extends perpendicular to the tooth surface 816C. The body 812C forms an upwardly facing receiver 822C with a groove 826C having a J-shaped cross-section configured to hold an archwire 880. The receiver 822C has an exposed exterior engagement surface 840C configured to releasably engage an appropriately shaped recess structure in an aligner tray (not shown in FIG. 8). The engagement surface 840C includes a rounded shoulder 842C and an undercut region 846C.

[0083] The body 812B of the attachment article 810B includes a spacer 830B that extends perpendicular to the tooth surface 816B. The body 812B forms a first upward receiver 826B-1 with a groove 822B-1 having a J-shaped cross-section configured to hold an archwire 880. The body 812B further includes a second downward receiver 822B-2 with a C-shaped cross-section and groove 826B-2. The receiver 822B-1 and receiver 822B-2 are separated by a middle portion 823B of the body 812B that is oriented generally parallel to the tooth surface 816B.

[0084] Receivers 822B-1 and 822B-2 have exposed outer engagement surfaces 840B-1 and 840B-2, respectively, that are configured to releasably engage appropriately shaped recess structures in an aligner tray (not shown in FIG. 8). Engagement surfaces 840B-1 and 840B-2 include respective rounded shoulders 842B-1 and 842B-2 and undercut regions 846B-1 and 846B-2, respectively.

[0085] As shown in FIGS. 9A-9C, in some embodiments, the wire-retaining groove of the fixture can be configured to allow the archwire to reside at a predetermined distance from the surface of the tooth. In system 900, tooth 920A includes fixture 910A with body 912A bonded to surface 916A. Body 912A includes downward receiver 922A with wire-retaining groove 926A configured to hold archwire 980. Similarly, tooth 920B includes fixture 910B bonded to its surface 916B. Fixture 910B includes body 912B with upward receiver 922B with wire-retaining groove 926B. Fixture 910C is bonded to surface 916C of tooth 920C and features body 912C with downward receiver 922C with wire-retaining groove 926C.

[0086] As shown in Figures 9B-9C, the groove 926A of the appliance 910A has a generally V-shaped cross section, and the archwire 980 abuts against the body 912A of the appliance 910A. In contrast, the groove 926C of the appliance 910C has a generally J-shaped cross section, and holds the archwire 980 directly against the tooth surface 916C. As shown in Figure 910C, in some embodiments of the appliance of the present disclosure, the tooth surface itself replaces one or more surfaces of the appliance, thus creating an inside corner or slot in which the archwire seats when a force is directed therein. Encircling two or more sides of the archwire results in the resultant force applied by the archwire being directed along a plane that is directed somewhere between at least two planes of the inside corner or inner side of the slot, and the archwire is directed into the slot to prevent pop-out. Thus, forces are reliably transferred from the archwire through the appliance to the tooth.

[0087] In some embodiments, a relatively simple fixture design such as that shown in Figures 9A-9C may even offer the dental practitioner the opportunity to mold the fixture chairside from a suitable composite material.

[0088] 10A-10B are schematic representations of an orthodontic system 1000 including a configuration of fixtures 1010 attached to lingual surfaces 1016 of teeth 1020. Each fixture 1010 includes a receiver 1022 and a wire-retaining groove 1026 selected to utilize an archwire (not shown in FIGS. 10A-10B) to move the teeth according to the wire-driven phase of a given patient treatment plan. As shown in FIG. 10B, the receiver design 1022 of the fixture 1010 provides an individual force vector 1090 selected for the desired movement of the teeth during the wire-driven treatment phase. While the shape of the receiver 1022 varies depending on the desired force vector to be applied to the teeth, each fixture 1010 has a substantially similar engagement surface 1040 configured to releasably engage a corresponding recess in an aligner tray (not shown in FIGS. 10A-10B).

[0089] Following completion of the wire-driven phase of treatment planning, the archwire is removed from the fixtures 1010, which remain in place on the teeth. The engagement surfaces 1040 of the fixtures 1010 can be used to releasably connect to aligner trays during the aligner phase of treatment which follows the wire-driven treatment phase.

[0090] Various embodiments of the present invention have been described. These and other embodiments are within the scope of the following claims.

Claims

1. A method for repositioning a patient's first malocclusion tooth, the method comprising: A wire driving stage, wherein the wire driving stage comprises: Supplying a plurality of fixtures, each fixture comprising a wire holding region and an engagement region, the engagement region comprising a shoulder configured to releasably engage a corresponding recess of an aligner tray; Attaching each of the plurality of fixtures to the patient's teeth; Inserting an arch wire into the wire holding region of the fixture to move the first malocclusion tooth from a first position to a second position different from the first position, the wire driving stage including: An aligner stage following the wire driving stage, the aligner stage comprising: Removing the arch wire from the wire holding region of the plurality of fixtures; Applying an aligner tray over the patient's teeth, the aligner tray comprising a plurality of cavities shaped to receive the first malocclusion tooth and to elastically position the first malocclusion tooth from the second position to a third position different from the second position, the aligner tray further comprising an array of depressions configured to releasably engage at least a portion of the engagement region of the fixture; A method including:

2. The method of claim 1, further comprising a second wire driving stage following the aligner stage.

3. An orthodontic treatment system, the orthodontic treatment system comprising: A plurality of fixtures, each fixture comprising a body having a first end portion configured to be joined to the surface of a patient's tooth and a second end portion opposite the first end portion, the second end portion comprising a receiver configured to hold an arch wire, the outer surface of the receiver comprising an engagement region with a shoulder; A plurality of arch wires insertable into the wire holding hooks of the fixtures; At least one aligner tray, each aligner tray comprising a plurality of cavities shaped to receive at least one tooth of the patient and to elastically position the at least one tooth, the aligner tray further comprising at least one recess configured to releasably engage the shoulder of the engagement region of at least one of the plurality of fixtures, an aligner tray; A dental orthodontic treatment system comprising. **Claim 4** An attachment device for dental orthodontic treatment, Comprising a body, the body A first end portion having a bonding portion configured to be bonded to the surface of a tooth, A second end portion opposite the first end portion, the second end portion having an outer surface with a wire retaining groove and an engagement region, the engagement region having a shoulder configured to releasably engage a corresponding recess of an aligner tray, An attachment device comprising. **Claim 5** The attachment device according to claim 4, wherein the wire retaining groove has one of a U-shaped cross-section configured to convert a force applied to the wire retaining groove into a tooth movement force in a direction substantially parallel to the plane of the bonding pad, and a J-shaped cross-section configured to convert a force applied to the wire retaining groove into a tooth movement force in a direction substantially perpendicular to the plane of the bonding pad.

Images