METHOD AND SYSTEM FOR OPTIMIZING DENTAL ALIGNER GEOMETRY

• US 20090191503A1
• Filed: 12/30/2008
• Published: 07/30/2009
• Est. Priority Date: 01/29/2008
• Status: Active Grant

• Current Assignee: Align Technology Incorporated
• Original Assignee: Align Technology Incorporated
• Inventors: Morton, John Y., Matov, Vadim, Kuo, Eric, Cao, Heng
• Granted Patent: US 8,439,672 B2
• Time in Patent Office: Days
• US Class Current: 433/24
• CPC Class Codes: A61B 6/032 Transmission computed tomography [CT]
• CPC Class Codes: A61B 6/51 for dentistry
• CPC Class Codes: A61C 7/00 Orthodontics, i.e. obtaining or maintaining the desired position of teeth, e.g. by straightening, evening, regulating, separating, or by correcting malocclusions
• CPC Class Codes: A61C 7/002 Orthodontic computer assisted systems
• CPC Class Codes: A61C 7/02 Tools for manipulating or working with an orthodontic appliance tools for placement of brackets A61C7/146; instruments for attaching elastic bands A61C7/306
• CPC Class Codes: A61C 7/08 Mouthpiece-type retainers or positioners, e.g. for both the lower and upper arch arch-shaped medicament applicators for teeth or gums A61C19/063; mouthguards for protecting the teeth of sportsmen A63B71/085
• CPC Class Codes: A61C 7/146 Positioning or placement of brackets; Tools therefor
• CPC Class Codes: A61C 7/16 specially adapted to be cemented to teeth
• CPC Class Codes: A61C 7/20 Arch wires A61C7/28 takes precedence
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing

Abstract

Method and system for establishing an initial position of a tooth, determining a target position of the tooth in a treatment plan, calculating a movement vector associated with the tooth movement from the initial position to the target position, determining a plurality of components corresponding to the movement vector, and determining a corresponding one or more positions of a respective one or more attachment devices relative to a surface plane of the tooth such that the one or more attachment devices engages with a dental appliance are provided.

Claims

1. A method of moving a tooth from an initial position to a target position, comprising:

establishing the initial position of the tooth;

determining the target position of the tooth in a treatment plan;

determining a sweep geometric path between the initial position and the target position and an associated movement vector for moving the tooth from the initial position to the target position; and

modifying a cavity geometry of a dental appliance for the tooth based on the determined sweep geometric path.

2. The method of claim 1, wherein modifying the cavity geometry includes defining one or more contact points on an inner surface of the dental appliance to contact a corresponding predetermined one or more surfaces of the tooth.

3. The method of claim 1, wherein modifying the cavity geometry includes defining one or more features on an inner surface of the dental appliance, wherein the one or more features is associated with the movement vector.

4. The method of claim 1, wherein the one or more features includes a dimple.

5. The method of claim 1, wherein the cavity geometry is modified to minimize friction between an inner surface of the dental appliance and the tooth.

6. The method of claim 1, wherein the sweep geometric path is a union geometry between the initial position and the target position, wherein the union geometry comprises a plurality of increments of a position to a subsequent position in the treatment plan.

7. The method of claim 1, wherein determining the sweep geometric path comprises determining a path that removes an interference between the initial position and the target position.

8. The method of claim 1, wherein the movement vector is configured to establish a force system applied by the dental appliance to the tooth to move the tooth from the initial position to the target position.

9. The method of claim 8, wherein the force system comprises at least one of a force, a moment of a force, and a moment of a couple.

10. The method of claim 1, further including determining a plurality of components corresponding to the movement vector.

11. The method of claim 10, wherein an inner surface of the dental appliance is configured to apply a respective one or more forces corresponding to the respective one of the plurality of components.

12. The apparatus of claim 10, wherein the plurality of components may provide one or more of a rotational displacement of the tooth, an angular displacement of the tooth, a linear displacement of the tooth, or one or more combinations thereof.

13. The method of claim 1, further comprising determining a corresponding position of one or more attachment devices relative to a surface plane of the tooth such that the one or more attachment devices is configured to engage with the dental appliance at a contact point to generate at least one of the components corresponding to the movement vector.

14. The method of claim 1, further comprising determining a surface area substantially perpendicular to the direction of the movement vector associated with the tooth movement from the initial position to the target position.

15. The method of claim 1, further comprising fabricating the dental appliance using rapid prototyping.

16. The method of claim 1, wherein the dental appliance comprises a polymeric shell.

17. A method of moving a tooth with a dental appliance having a specific cavity geometry, comprising:

establishing an initial position of the tooth;

determining a target position of the tooth in a treatment plan;

calculating a first movement vector associated with movement of the tooth from the initial position to the target position;

determining a component corresponding to the first movement vector; and

determining a corresponding position of one or more attachment devices relative to a surface plane of the tooth such that the one or more attachment devices is configured to engage with the dental appliance at a contact point to generate the component corresponding to the first movement vector.

18. The method of claim 17, further comprising generating a plurality of dental appliances having geometries selected to progressively reposition the teeth, wherein the dental appliances comprise polymeric shells having cavities and wherein the cavities of successive shells have different geometries shaped to receive and resiliently reposition teeth from one arrangement to a successive arrangement.

19. The method of claim 17, wherein the plurality of components comprises at least one of a magnitude of a force and a direction of a force.

20. The method of claim 17, wherein the attachment device is configured to apply a predetermined force on the dental appliance substantially at the surface plane of the tooth.

21. The method of claim 17, wherein the plurality of components is configured to provide one or more of a rotational displacement of the tooth, an angular displacement of the tooth, a linear displacement of the tooth, or one or more combinations thereof.

22. The method of claim 17, wherein the one or more attachment devices includes a plurality of dental attachment devices provided on the tooth in an abutting position relative to each other.

23. The method of claim 22, wherein the dental appliance is configured to physically contact each of the plurality of abutting dental attachment devices sequentially and separately for a period of time.

24. The method of claim 17, further comprising attaching the one or more attachment devices on the surface plane of the tooth.

25. The method of claim 17, further comprising:

after determining the corresponding position of the one or more attachment devices, determining a second movement vector associated with movement of the tooth to a subsequent target position.

26. The method of claim 25, further comprising modifying a shape of the dental appliance such that the dental appliance is configured to generate one or more components corresponding to the second movement vector.

27. The method of claim 17, wherein the dental appliance comprises a polymeric shell.

28. The method of claim 17, further comprising fabricating the dental appliance using rapid prototyping.

29. An apparatus for modeling a dental appliance and positioning of attachment devices for moving a tooth, comprising:

a data storage unit;

a processing unit coupled to the data storage unit, wherein the processing unit is configured to determine a first position of a tooth, determine a second position for the tooth in a treatment plan, calculate a movement vector associated with a sweep geometric path to move the tooth from the first position to the second position,

30. The apparatus of claim 29, wherein the data storage unit comprises a database comprising at least one patient treatment history;

orthodontic therapies, orthodontic information, and diagnostics.

31. The apparatus of claim 29 further including:

determining a component corresponding to the movement vector, and

determining a position of one or more attachment devices relative to a surface plane of the tooth such that the one or more attachment devices engages with the dental appliance at a contact point to generate the component corresponding to the movement vector.

32. The apparatus of claim 31, wherein the one or more attachment devices is configured to apply a predetermined force on the dental appliance substantially at the surface plane of the tooth.

33. The apparatus of claim 31, wherein the one or more attachment devices may include a plurality of dental attachment devices provided on the tooth in an abutting position relative to each other, wherein the dental appliance may be configured to physically contact each of the plurality of abutting dental attachment devices sequentially and separately for a predetermined period of time.

34. The apparatus of claim 31, wherein the plurality of components may provide one or more of a rotational displacement of the tooth, an angular displacement of the tooth, a linear displacement of the tooth, or one or more combinations thereof.

35. The apparatus of claim 29, wherein the processing unit is further configured to modify a cavity geometry of the dental appliance based on the sweep geometric path between the first position and the second position.

36. The apparatus of claim 29, wherein the processing unit is further configured to define a contact point on an inner surface of the dental appliance to contact a corresponding predetermined surface of the tooth.

37. The apparatus of claim 29, wherein the processing unit is further configured to define a feature on an inner surface of the dental appliance, wherein the feature is associated with the movement vector.

38. The apparatus of claim 29, wherein the sweep geometric path is a union geometry between the first position and the second position, wherein the union geometry comprises a plurality of increments of a position to a subsequent position in the treatment plan.

39. The apparatus of claim 29, wherein the movement vector is configured to establish a force system applied by the dental appliance to the tooth to move the tooth from the first position to the second position.

40. The apparatus of claim 39, wherein the force system comprises at least one of a force, a moment of a force, and a moment of a couple.