Patent Application
20230293267
The present invention relates generally to the field of orthodontic treatment, and more particularly to orthodontic aligners configured to be used in conjunction with an elastic member.
Orthodontics is the practice of manipulating teeth to correct malocclusions between the teeth of the upper and lower dental arches. Typically, treatment of malocclusions includes the use of an orthodontic appliance that applies corrective forces to the teeth. Over time, these corrective forces coerce the teeth to move into their orthodontically correct positions.
Orthodontists may utilize orthodontic appliances referred to as “dental aligners,” or simply “aligners” to move teeth. Aligners are generally supplied as a series of removable appliances that incrementally reposition the patient's teeth from their initial orientation to their orthodontically correct orientation. Patients being treated with aligners can insert and remove the aligners at will, and therefore do not need to visit the orthodontist for adjustments. Rather, when the currently worn aligner has moved the teeth to at or near a final orientation for that aligner, the patient merely begins using the next aligner in the series according to a treatment plan.
To fabricate aligners, the orthodontist may first obtain a 3D computer model of the patient's dentition. This model may be generated, for example, by taking an impression of the dentition and scanning the impression into a computer or using an intraoral scanner to directly image the patient's dentition. Once the 3D computer model has been obtained, the orthodontist determines a target orientation of the teeth that provides a corrected dentition. Alternatively, a software algorithm may automatically generate a target orientation of the teeth in accordance with specific programmed criteria. Multiple computer models may then be generated, with each model representing a 3D positive mold of the patient's teeth corresponding to an incremental orientation of the dentition from an initial orientation to a target orientation. The incremental orientations from initial to target orientations may move the patient's teeth according to a proposed treatment plan. Treatment plans typically include numerous stages of movement from an initial orientation to a target orientation of the teeth. Depending on the degree of tooth movement, treatment plans may include a plurality of aligners that are worn in a predetermined sequence from an initial orientation to a final orientation.
The output of the above-described treatment planning process is a series of 3D positive molds of the patient's teeth represented as a series of digital design files. Once the series of 3D molds has been designed, each aligner is fabricated. Fabrication of the aligners typically involves first printing each positive mold of the patient's teeth using an additive manufacturing method and forming plastic sheets over each mold constructed of target orientations of the dentition according to the computer models. After forming, waste material must be trimmed away to produce the aligner. Trimming may utilize CNC milling or another computer controlled cutting system. Additional post processing steps are also performed during printing of individual dental molds and after forming and trimming of the aligner atop a mold.
Aligners may be configured to be used in conjunction with dental attachments, commonly referred to by Orthodontists as “attachments”. Attachments are solid objects bonded to a tooth, typically using an adhesive, that protrude outwardly from the tooth. When a dental attachment is used, the dental aligner is fabricated to fit tightly over both the attachment and the corresponding tooth such that the forces on the tooth may be increased. The attachment effectively provides an additional contact point between the aligner and the corresponding tooth from which to create force on the tooth. Among many other benefits, this improved force application allows for better control and predictability of tooth movement as well as decreased treatment times. When used in conjunction with aligner treatment, attachments allow more aggressive treatment plans and the correction of more significant and pronounced dental malocclusions.
Aligners may also be configured to be used in conjunction with an elastic member, such as elastic bands. Elastic bands are configured to permit application of an additional corrective force on the jaw of the patient and can be useful in correcting underbite and overbite. Attachment of an elastic band to an aligner is typically achieved by modifying a gingival edge of the aligner to create an attachment point. For example, the gingival edge may be cut in two locations and the elastic member is then looped through the cuts. An intermediate portion of the aligner is bent outward due to the elastic member. Attaching an elastic member at this location can create problems. First, the increased corrective forces applied to the dental aligner by the elastic member adds stress at the location of the attachment point. The added stress is generally the highest at the cuts. Too much stress for too long at these locations can cause the aligner material to deform and prematurely fail, such as by bending, ripping, and/or tearing. When the aligner fails, the patient must replace the aligner. This prolongs treatment time. Second, cutting the gingival edge of the aligner introduces a defect at or near the gingival edge and so reduces the structural integrity of the aligner, potentially making it less effective than it was designed to be. This may also prolong treatment time because the cut aligners may not be capable of moving teeth according to the designed treatment plan.
While generally successful, further improvements in dental aligners and in orthodontic treatment are needed.
A first embodiment of the present invention is an aligner for use in orthodontic treatment of a patient, comprising a hollow shell and a feature. The hollow shell includes a buccal sidewall, an occlusal wall, and a lingual sidewall and defines a plurality of cavities. The plurality of cavities is configured to receive respective ones of the patient's teeth. The sidewalls define a gingival edge that forms an opening in the hollow shell. The feature is positioned on or in at least one of the sidewalls and is spaced apart from the gingival edge, and is configured to receive an elastic member.
A further embodiment of the present invention is an aligner wherein the feature comprises a protrusion in the at least one sidewall and an opening. The protrusion at least partially defines the cavity and is configured to space the sidewall apart from the patient's tooth. The opening is through the sidewall proximate the protrusion or through the protrusion.
A further embodiment of the present invention is an aligner wherein the feature comprises a through-bore in the sidewall. The through-bore includes an edge that defines a shape. In some embodiments, the edge defines a substantially circular shape. In other embodiments, the edge includes at least one substantially linear portion that is most proximal to the gingival edge and is substantially parallel to the gingival edge. In some further embodiments, the edge defines a substantially polygonal shape.
A embodiment of the present invention is an aligner wherein the feature comprises an add-on hook attached on to the sidewall. The add-on hook includes a projection spaced apart from the sidewall thereby defining a recess between the projection and the sidewall. The add-on hook is fabricated separately from the aligner. In some further embodiments, the sidewall comprises a protrusion on which the add-on hook is attached. In some even further embodiments, the protrusion is configured to engage with a dental attachment on the patient's tooth. In some embodiments, the add-on hook may include a retention bump extending toward the recess that is configured to retain the elastic member. In various embodiments, the projection is curved relative to the sidewall.
A further embodiment of the invention is an aligner wherein the aligner is configured to apply a greater repositioning force than the aligner alone to the respective ones of the patient's teeth or the patient's jaw when an elastic member is attached to the feature.
A further embodiment of the invention is an aligner, wherein the feature comprises at least one of (1) a protrusion in the at least one sidewall that at least partially defines the cavity, the protrusion being configured to space the sidewall apart from the patient's tooth, and an opening through the sidewall proximate the protrusion or through the protrusion; (2) a through-bore in the sidewall, wherein the through-bore includes an edge that defines a shape; and (3) an add-on hook including a projection spaced apart from the sidewall thereby defining a recess between the projection and the sidewall, wherein the add-on hook is fabricated separately from the aligner and is attached on to the sidewall. A further embodiment of the invention is an aligner for use in orthodontic treatment of a patient comprising a hollow shell, a feature, and an elastic member. The hollow shell includes a buccal sidewall, an occlusal wall, and a lingual sidewall and defines a plurality of cavities to receive respective ones of the patient's teeth. The sidewalls define a gingival edge that forms an opening in the hollow shell. The feature is positioned on or in the at least one of the sidewalls and is spaced apart from the gingival edge. The elastic member is configured to attach to the feature. In some embodiments, the elastic member is attached to the feature using a lark's head knot. In various embodiments, the elastic member comprises a hook that attaches the elastic member to the feature. In some further embodiments, the hook includes a retention bump and the feature includes a retention bump receptacle, wherein the retention bump is configured to be received by the retention bump receptacle when the elastic member is attached to the feature by the hook.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the general description of the invention given above, and the detailed description given below, serve to explain the principles of the invention. Similar reference numerals are used to indicate similar features throughout the various figures of the drawings.
Embodiments of the invention are directed to an aligner including a feature on or in at least one of a lingual sidewall or a buccal sidewall (also referred to as a labial sidewall herein) at which an elastic member may be attached to the aligner. Advantageously, with the attached elastic, embodiments of the aligner improve the range of forces available for application during orthodontic treatment without sacrificing the structural integrity of the aligner. This is achieved by avoiding modification of a gingival edge of the aligner. The feature that receives the elastic member is spaced apart from the gingival edge and so avoids negatively affecting the structural integrity of the aligner while still providing a location at which an elastic member may be secured. In other words, aligners according to embodiments of the invention lack modification of the gingival facing edge of the aligner during manufacturing or immediately prior to treatment (e.g., by the orthodontist or clinician, such as by cutting the gingival edge with a pair of scissors). An elastic member may be secured to the aligner at the location of the feature and so may be utilized to add specific forces (e.g., translational) to the patient's jaw that would otherwise be unavailable in the absence of the elastic member. This may be achieved without premature failure of the aligner. Application of forces through the elastic are transferred to the aligner at a location and will not degrade the structural integrity of the aligner for the period of use of that aligner. Because each aligner is essentially customized to the patient's teeth in a particular pre-planned orientation, the location at which a feature may be formed may vary according to the forces needed during treatment. In the figures below, exemplary embodiments of the invention are shown in which the feature permits an elastic member to be secured to the aligner.
To these and other ends, referring to
With further reference to
With continued reference to the exemplary embodiment shown in
With further reference to
The protrusion 32 may be formed in various ways. For example, the protrusion 32 may be formed by fabricating the aligner 10 over a mold of a patient's teeth that includes an artificially built-up feature on one or more 3D printed structures in the shape of the desired protrusion 32. This can be accomplished by designing a structure on one or more of the 3D modeled teeth in software, which will be printed on the mold of the patient's teeth when the mold is printed using an additive manufacturing method. The result is that when raw aligner material is thermoformed on top of such a mold to form aligner 10, the artificially built-up feature will be reflected in the aligner 10. Since the designed structure does not reflect an actual part of the patient's tooth, the space 34 (i.e., a “gap”) will result at the location of the structure when the formed aligner 10 is worn by the patient. In this way, the protrusion 32 may have the same thickness as the sidewall 22. Another way of forming the protrusion 32 is to add extra material to the portion of the sidewall 22 at which the protrusion 32 is formed. This adds to the through-thickness of the sidewall 22. The extra material can be removed from the portion of the sidewall 22 proximal to the cavity 14a to create the space 34 using a conventional means of removing materials. The placement of the protrusion 32 may be determined based on clinical considerations including, but not limited to, design and forces applied to the patient's tooth 13a or patient's jaw 26 (including but not limited to tangential forces such as tangential force 41 shown in
During use and with reference to the exemplary embodiment shown in
With reference to
Embodiments are not limited to an elastic member 40 attached to the aligner 10 at the protrusion 32 via a hook 42. Although not shown, the aligner 11 may include a protrusion configured to attach to the elastic 40 as described above. Further, multiple hooks are contemplated. In some such embodiments, the elastic member 40 is coupled to a plurality of hooks 42 by which the elastic 40 may be attached to both aligners 10, 11 at the protrusion 32 and at a second protrusion respectively as described above. In this way, the elastic member 40 may be stretched between aligners 10, 11 so that additional forces may be applied to one or more teeth 13 on both the mandible jaw 26 and the maxillary jaw 28.
Moreover, embodiments are not limited to a single protrusion 32 per aligner. In that regard, both of the aligners 10, 11 may include a plurality of protrusions 32 as described above, and each of a plurality of the elastic members 40 may be attached to a protrusion 32 on both of the aligners 10, 11 via a plurality of hooks 42 (not shown). In this way, additional forces may be applied to the patient's jaws 26, 28. Treatment of the patient's malocclusion may be further hastened or otherwise further improved by the use of the elastic 40 to apply a greater corrective force to the patient's dentition or additional corrective forces to the patient's dentition as disclosed above.
Referring now to
The size and location of the through-bore 60 are selected to avoid significant stress at the edge 16 of the shell 12 and to allow for the elastic 40 to attach to the through-bore 60 (described below). As such, the through-bore is spaced apart from the edge 16 toward the occlusal wall 20. The placement of the through-bore 60 may be determined using clinical considerations, including but not limited to design, structural integrity of the aligner, and forces applied to the patient's tooth 13a or jaw 26 (including but not limited to tangential forces such as tangential force 41 shown in
The through-bore 60 includes a through-bore edge 62 that defines a shape in the sidewall 22. As shown, the edge 62 defines a substantially circular through-bore 60. However, embodiments of the invention are not limited to circular through-bores 60 such as that shown. A portion of the edge 62 may be substantially parallel to gingival edge 16 (not shown). In some such embodiments of the invention, the portion of edge 62 that is substantially parallel to gingival edge 16 is also the most proximal portion of the through-bore 60 to edge 16 (not shown). In that regard, the through-bore edge 62 may define a polygonal shape such as, but not limited to, a triangular, square, hexagonal, octagonal, or other suitable polygonal shape. Further, the through-bore edge may define an irregular shape, such as a substantially semi-circular shape (not shown). In some further embodiments of the semi-circularly shaped through bore edge, the semi-circular shape resembles a capital letter “D” rotated ninety degrees counterclockwise.
In the exemplary embodiment shown, the elastic member 40 is tied directly to the aligner 10 via the through-bore 60. As shown, the elastic member 40 passes through the bore 60 and is wrapped around the gingival edge 16. The elastic 40 may be a continuous band tied to the aligner 10 using the lark's head knot (also known as the cow hitch knot). The elastic member 40 may be tied to the aligner 10 by looping one end of the elastic band 40 around edge 16, internal surface 68, and edge 62. Opposing loops in ends of the elastic band 40 may be tied by pulling one loop (i.e., one end) of the elastic band 40 through the opposing loop (i.e., the other end) of the elastic band 40 until the knot is taut. In this way, the elastic 40 attaches to the aligner 10 at the through-bore 60 as shown in
Embodiments of the invention are not limited to the elastic member 40 being tied to one or both aligners 10 and 11 between the through-bore 60 and the edge 16. For example, both the aligners 10, 11 may include a plurality of through-bores 60 as described above. In this way, a plurality of the elastic members 40 may be tied to a through-bore 60 on both aligners 10, 11. In this way, additional forces may be applied to the patient's jaws 26, 28. Treatment of the patient's malocclusion may be further hastened or otherwise further improved by the use of an elastic 40 to apply a greater corrective force to the patient's dentition or additional corrective forces to the patient's dentition as disclosed above.
Referring now to
A portion of the hook 80 extends beyond a perimeter of the buccal protrusion 81 to form at least one projection 82. The projection 82 is therefore a result of a mismatch in position and/or size between the hook 80 and the protrusion 81 at the perimeter of buccal protrusion 81. The protrusion 81 extends buccally away relative to surrounding portions of the sidewall 22 such that the projection 82 is spaced from the sidewall 22 to create a recess 86. In the exemplary embodiments shown, the projection 82 extends substantially parallel to the buccal sidewall 22 from the buccal protrusion 81 and is pointed in substantially gingival direction (i.e., toward the edge 16) from the protrusion 81 and so is between the edge 16 and the protrusion 81. However, embodiments are not limited to the position shown. For example, the projection 82 may extend distally, mesially, or occlusally from the protrusion 81 with the elastic member 40 being stretched in generally the opposite direction when attached as described below. This ensures that the elastic member 40 remains securely attached to the aligner 10 when the elastic member 40 is stretched during use. In some embodiments, the projection 82 is curved concavely relative to the buccal sidewall 22 while the add-on hook is attached to the buccal protrusion 81 (not shown).
With reference to
With further reference to
With reference to
With reference to
Although not shown, the protrusion 81 may be formed in various ways. For example, the protrusion 81 may be formed by fabricating the aligner 10 over a mold of a patient's teeth that includes an artificially built-up feature on one or more 3D printed structures in the shape of the desired protrusion 81. This can be accomplished by designing a structure on one or more of the 3D modeled teeth in software, which will be printed on the mold of the patient's teeth when the mold is printed using an additive manufacturing method. The result is that when raw aligner material is thermoformed on top of such a mold, the artificially built-up feature will be reflected in the aligner 10 formed. Since the designed structure is artificial and does not form an actual part of the patient's tooth, a “gap” will result at the location of the structure when the aligner 10 is applied to the patient's teeth 13 (i.e., worn by the patient). In this way, the protrusion 81 may have the same thickness as the sidewall 22 and the protrusion 81 may be configured to engage with a dental attachment 84. Another way of forming the protrusion 81 is to add extra material to the portion of the sidewall 22 at which the protrusion 81 is formed (not shown). In embodiments where the protrusion 81 is configured to engage with the dental attachment 84, excess material can be removed from the portion of the sidewall 22 proximal to the cavity 14a using a conventional means of removing materials including, but not limited to, hole punching, drilling, cutting, puncturing, boring, end milling, or other similar methods (not shown).
As shown, the elastic 40 is attached to the add-on hook 80 when a portion of the elastic 40 is received in the recess 86 and another portion of the elastic 40 is extended in a direction generally opposite the projection 82. Advantageously, the elastic 40 is securely attached to the hook 80 at a location spaced-apart from the edge 16 of the aligner 10. Thus, forces produced by the elastic 40 when it is elastically stretched, such as when it is attached to a separate location at another position in the patient's mouth, are transferred to the sidewall 22 via the hook 80 and are efficiently distributed to the aligner 10. Additionally, the forces produced by the elastic member 40 are distributed in an area around the hook 80 thereby avoiding subjecting the edge 16 or any portion thereof to direct loads from the stretched elastic 40. In this way, treatment of the patient's malocclusion may be hastened or otherwise improved by the use of the elastic 40 with a decreased risk premature failure of the aligner 10, 11 at or near the gingival edge 16 due to the added loading.
Embodiments of the invention are not limited to the elastic 40 being attached to a single add-on hook 80 of aligner 10. Although not shown, the aligner 11 may include an add-on hook configured to attach to the elastic 40 as described above. In some such embodiments, the elastic 40 may be attached to the hook 80 on aligner 10 and a second hook on aligner 11. In this way, the elastic 40 may be stretched between aligners 10, 11 so that additional forces may be applied to one or more teeth 13 on both the mandible jaw 26 and the maxillary jaw 28. Embodiments are not limited to a single add-on hook 80 per aligner. In that regard, both the aligners 10, 11 may include a plurality of hooks 80 as described above, and each of a plurality of the elastic members 40 may be attached to an add-on hook 80 on both the aligners 10, 11 (not shown). In this way, additional forces may be applied to the patient's jaws. Treatment of the patient's malocclusion may be further hastened or otherwise further improved by the use of an elastic 40 to apply a greater corrective force to the patient's dentition or additional corrective forces to the patient's dentition as disclosed above.
Referring now to
As shown, the projection 102 extends from the body 104 so that, in cross-section, the feature 30 has a dog-legged shape with the projection 102 extending substantially parallel to the sidewall 22. The body 104 extends buccally away from sidewall 22 such that the projection 102 is spaced from the sidewall 22 to create a recess 106. As shown, the projection 102 extends in a gingival direction. However, embodiments are not limited to the orientation shown. For example, the projection 102 may extend distally, mesially, or occlusally from the body 104 with the elastic member 40 being stretched in generally the opposite direction when attached as described below. Generally, the projection 102 is positioned on the body 104 on the same side as the direction in which the body 104 extends from the shell 12. This ensures that the elastic member 40 remains securely fastened to the aligner 10 when the elastic member 40 is stretched during use. In some embodiments, the projection 102 is curved concavely relative to the sidewall 22 while the hook 100 is attached to the shell 12 (not shown).
With reference to
With reference to
Embodiments of the invention are not limited to the elastic 40 being attached to a single add-on hook 100 of aligner 10. Although not shown, the aligner 11 may include an add-on hook configured to attach to the elastic 40 as described above. In some such embodiments, the elastic 40 may be attached to the hook 100 on aligner 10 and a second hook on aligner 11. In this way, the elastic 40 may be stretched between aligners 10, 11 so that additional forces may be applied to one or more teeth 13 on both the mandible jaw 26 and the maxillary jaw 28. Embodiments are not limited to a single add-on hook 80 per aligner. In that regard, both the aligners 10, 11 may include a plurality of hooks 100 as described above, and each of a plurality of the elastic members 40 may be attached to an add-on hook on both the aligners 10, 11 (not shown). In this way, additional forces may be applied to the patient's jaws 26, 28. Treatment of the patient's malocclusion may be further hastened or otherwise further improved by the use of an elastic 40 to apply a greater corrective force to the patient's dentition or additional corrective forces to the patient's dentition as disclosed above.
Referring generally to
With further reference to
While the present invention has been illustrated by the description of one or more embodiments thereof, and while the embodiments have been described in considerable detail, they are not intended to restrict or in any way limit the scope of the appended claims to such detail. The various aspects of the invention shown and described herein may be used alone or in any combination. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and methods and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the scope or spirit of Applicants' general inventive concept.
This application claims priority to U.S. Provisional Patent Application No. 63/320,733, filed Mar. 17, 2022, the entire content of which is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 63320733 | Mar 2022 | US |
