ORTHODONTIC SYSTEMS AND METHODS INCLUDING PARAMETRIC ATTACHMENTS

• US 20100138025A1
• Filed: 11/20/2009
• Published: 06/03/2010
• Est. Priority Date: 11/20/2008
• Status: Active Grant

• Current Assignee: Align Technology Incorporated
• Original Assignee: Align Technology Incorporated
• Inventors: Cao, Heng, Pesenti, Bastien, Matov, Vadim, Kimura, Ryan, Cheng, Jihua, Morton, John
• Granted Patent: US 9,161,823 B2
• Time in Patent Office: Days
• US Class Current: 700/104
• 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 7/08 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 7/14 Brackets A61C7/28 takes precedence; Fixing brackets to teeth
• CPC Class Codes: A61C 7/146 Positioning or placement of brackets; Tools therefor
• CPC Class Codes: G06F 17/10 Complex mathematical operations function generation by table look-up G06F1/03; evaluation of elementary functions by calculation G06F7/544
• CPC Class Codes: G06F 30/00 Computer-aided design [CAD]

Abstract

Orthodontic systems and related methods are disclosed for designing and providing improved or more effective tooth moving systems for eliciting a desired tooth movement and/or repositioning teeth into a desired arrangement. Methods and orthodontic systems of the invention include tooth attachments having improved or optimized parameters selected or modified for more optimal and/or effective application of forces for a desired/selected orthodontic movement. Attachments of the present invention can be customized to a particular patient (e.g., patient-customized), a particular movement, and/or a sub-group or sub-set of patients, and configured to engage an orthodontic tooth positioning appliance worn by a patient, where engagement between the attachment and orthodontic appliance results in application of a repositioning force or series/system of forces to the tooth having the attachment and will generally elicit a tooth movement.

Claims

1. A computer implemented method for designing a tooth movement system for eliciting a selected movement of a patient'"'"'s tooth, the method comprising:

receiving a digital model of the patient'"'"'s tooth;

determining a desired force system for eliciting the selected tooth movement; and

designing a patient-customized attachment configured to engage an orthodontic appliance when worn by a patient and apply a repositioning force to a tooth corresponding to the selected force system, the attachment comprising one or more parameters having values selected based on the digital model, the selected force system, and one or more patient-specific characteristics, thereby providing improved application of the selected force system to the patient'"'"'s tooth.

2. The method of claim 1, wherein the selected tooth movement comprises extrusion, intrusion, rotation, translation, or tipping.

3. The method of claim 1, wherein the tooth movement comprises first, second or third order movements.

4. The method of claim 1, wherein the desired force system is calculated at least partially based on data from orthodontic literature, experimental modeling, virtual modeling, clinical information, biomechanical principles, or minimization of unwanted forces.

5. The method of claim 1, one or more parameter values are selected based on tooth morphology.

6. The method of claim 1, wherein a parameter comprises an attachment geometry feature, attachment location on the tooth, orientation, and/or probability of engagement between the attachment and appliance.

7. The method of claim 1, wherein a parameter value is selected from an identified range of values.

8. The method of claim 1, wherein a parameter value is modified based on a morphological feature of the patient'"'"'s tooth.

9. The method of claim 1, wherein a desired movement, desired force system, and/or a parameter is defined with respect to an anatomical feature reference.

10. The method of claim 9, wherein the reference comprises a long axis, an orthodontic reference point, plane or occlusal plane of the patient'"'"'s dentition, one or more skeletal points or planes, or a soft tissue of the patient.

11. The method of claim 1, wherein a patient-specific characteristic comprises tooth morphology, tooth or tooth surface orientation, or a prescribed tooth movement path.

12. A method for generating a tooth movement system comprising a tooth attachment configured to engage an orthodontic appliance worn by a patient and apply a repositioning force system to a tooth corresponding to a selected movement of the patient'"'"'s tooth, the method comprising:

determining a desired force system to be applied to the patient'"'"'s tooth so as to elicit the selected tooth movement;

selecting a first attachment from a group of non-custom attachments;

modeling a first force system applied to a tooth having the first attachment and engaged with an orthodontic appliance;

generating an optimized attachment comprising modifying one or more parameter values of the first attachment such that a second force system applied to the tooth having the optimized attachment and engaged with an orthodontic appliance worn by the patient more closely corresponds to the desired force system than the first force system.

13. An orthodontic system for delivery of a tooth movement force to a patient'"'"'s tooth, comprising:

a patient customized orthodontic attachment configured to engage an orthodontic appliance when worn by a patient and apply a repositioning force system to a tooth corresponding to a selected force system, the attachment comprising one or more parameters having values modified or selected based on the selected force system and one or more patient-specific characteristics.

14. A method for designing a tooth movement system comprising one or more tooth attachments for eliciting a selected movement of a patient'"'"'s tooth, the method comprising:

determining force or torque values of a desired force system for eliciting the selected tooth movement; and

designing a movement optimized or patient-customized attachment configured to engage an orthodontic appliance when worn by a patient and apply a repositioning force to the tooth, the attachment comprising one or more parameter values modified based on the determined force or torque values such that the applied repositioning force substantially matches the desired force system.

15. A method for designing a tooth movement system, comprising:

identifying a range of force or torque values corresponding to a desired force system to be applied to a tooth so as to elicit a selected tooth movement;

modeling a first force or torque value applied to a tooth when a first attachment disposed on the tooth is engaged with an orthodontic appliance, the first attachment having parameters affecting the force or torque applied to the tooth during engagement, wherein the first force or torque value is identified as being within the range of values;

generating an optimized attachment comprising modifying one or more parameter values of the first attachment such that a second force or torque is applied to a tooth having the optimized attachment and engaged with an orthodontic positioning appliance, wherein the second force or torque value is higher or lower in the range of values compared to the first force system and selected to optimize force/torque application to a tooth during orthodontic treatment.

16. The method of claim 15, wherein the selected tooth movement comprises an intrusion, extrusion, rotation, translation or tipping.

17. The method of claim 15, wherein the optimized attachment is beveled incisally or gingivally and modifying one or more parameter values comprises modifying a surface angle of the beveled attachment.

18. The method of claim 15, wherein the selected tooth movement is an extrusion, the first attachment is beveled gingivally, and modifying one or more parameter values comprises modifying a surface angle of the beveled attachment.

19. An orthodontic repositioning system, comprising an optimized attachment as in claim 15, and an orthodontic appliance configured to engage the optimized attachment when the attachment is disposed on the patient'"'"'s tooth and the appliance is worn by the patient.

20. A method for designing an attachment for eliciting a selected movement of a patient'"'"'s tooth, the method comprising:

identifying an initial position of an attachment on a tooth at a location on a digital model of the patient'"'"'s dentition;

computing attachment parameters based on the initial position of the attachment and a geometry of the tooth, wherein each attachment parameter is associated with a predetermined range of values corresponding to optimal force or optimal torque for the selected movement of the tooth; and

in the event that at least one value of the computed parameters is not within the predetermined range of values, modifying at least one of the attachment parameters and the position of the attachment on the tooth such that all of the attachment parameters are within the predetermined range of values.

21. The method of claim 20, wherein the attachment parameters comprise at least one of:

an arm vector, an arm length, a clipping plane area, a clipping plane width and a clipping plane length.

22. The method of claim 20, wherein the attachment parameters are modified such that the attachment does not collide with an object throughout all or a portion of treatment of the tooth.

23. The method of claim 22, wherein the object comprises one of another tooth, an orthodontic attachment on a tooth and an appliance.

24. The method of claim 20, further comprising:

re-modifying the position of the of the attachment when the attachment at the modified position does not provide a solution that results in the desired movement of the patient'"'"'s tooth without collision between the attachment and an object throughout all or a portion of treatment of the tooth.

25. The method of claim 24, wherein the object comprises one of another tooth, an orthodontic attachment on a tooth and an orthodontic appliance.

26. The method of claim 22, further comprising:

prioritizing the attachment parameters.

27. A computer program product having a computer readable medium storing a set of code modules which when executed by a processor of a computer system cause the processor to model an attachment for eliciting a selected movement of a patient'"'"'s tooth, the computer program product comprising:

code for identifying an initial position of an attachment on a tooth at a location on a digital model of the patient'"'"'s dentition;

code for computing attachment parameters based on the initial position of the attachment and a geometry of the tooth, wherein each parameter is associated with a predetermined range of values corresponding to optimal force or optimal torque for the selected movement of the tooth; and

code for modifying at least one of the attachment parameters and the position of the attachment on the tooth such that all of the attachment parameters are within the predetermined range of values.