Manipulating a digital dentition model to form models of individual dentition components

• US 7,123,767 B2
• Filed: 10/15/2002
• Issued: 10/17/2006
• Est. Priority Date: 06/20/1997
• Status: Expired due to Term

• Current Assignee: Align Technology Incorporated
• Original Assignee: Align Technology Incorporated
• Inventors: Chishti, Muhammad, Bala, Gregory P., Wen, Huafeng, Jones, Timothy N.
• Primary Examiner(s): Bella, Matthew C.
• Assistant Examiner(s): STREGE, JOHN B
• Application Number:
  US10/271,665
• Publication Number:
  US 20030039389A1
• Time in Patent Office: 1,463 Days
• Field of Search: 382/100, 382/128, 382/154, 345/419, 433/2, 433/24, 433/213, 433/214, 700/163, 348/77
• US Class Current: 382/154
• CPC Class Codes: A61C 2007/004 Automatic construction of a set of axes for a tooth or a plurality of teeth
• 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 9/00 Impression cups, i.e. impression trays; Impression methods computer-assisted sizing A61C13/0004; instruments for determining occlusion A61C19/05
• CPC Class Codes: A61C 9/0046 Data acquisition means or methods

Abstract

A programmed computer is used to create a digital model of an individual component of a patient'"'"'s dentition. The computer obtains a 3D digital mode of the patient'"'"'s dentition, identifies points in the dentition model that lie on an inter-proximal margin between adjacent teeth in the patient'"'"'s dentition, and uses the identified points to create a cutting surface that separates portions of the dentition model representing the adjacent teeth.

Claims

1. A computer-implemented method for use in creating a digital model of an individual component from a digital model of a patient'"'"'s dentition and adapted to generate one or more appliances used in treating the patient, the method comprising:

obtaining a 3D digital model of the patient'"'"'s dentition;

creating a digital cutting surface representing an interproximal margin between adjacent teeth in the patient'"'"'s dentition and a surface that represents a tooth root, as to separate portions of the dentition model representing the adjacent teeth; and

generating one or more appliances used in treating the patient based on the separated dentition model.

2. The method of claim 1, further comprising displaying 2D cross sections of the digital model and receiving input from a human operator identifying approximate points at which the interproximal margin between the adjacent teeth meets gingival tissue.

3. The method of claim 2, wherein the dentition model includes a 3D volumetric model of the patient'"'"'s digital and the input from the human operator identifies two voxels in the volumetric model.

4. The method of claim 3, further comprising defining a neighborhood of voxels around each of the two voxels identified by the human operator, where each neighborhood includes voxels representing the digital model and voxels representing a background image.

5. The method of claim 4, further comprising applying a computer-implemented test to select a pair of voxels, both representing the background image, that lie closest together, where each neighborhood contains one of the voxels.

6. The method of claim 3, further comprising automatically identifying voxels on another 2D cross section that represent the interproximal margin.

7. The method of claim 6, wherein automatically identifying voxels on another 2D cross section includes:

defining a neighborhood of voxels around each of the selected voxels, where each neighborhood includes voxels representing the digital model and voxels representing a background image;

projecting the neighborhoods onto the other 2D cross section; and

selecting two voxels in the projected neighborhoods that represent the interproximal margin.

8. The method of claim 7, wherein selecting two voxels in the projected neighborhoods includes selecting a pair of voxels, both representing the background image, that lie closest together, where each of the neighborhoods contains one of the voxels.

17. The method of claim 1, further comprising using the surface representing a tooth root to separate portions of the digital model representing the tooth roots from portions representing gingival tissue.

18. The method of claim 17, further comprising connecting the portions of the digital model representing the tooth root to the portion representing the tooth.

9. A computer program, stored on a tangible storage medium, for use in creating a digital model of an individual component from a digital model of a patient'"'"'s dentition and adapted to generate one or more appliances used in treating the patient, the program comprising executable instructions that, when executed by a computer, cause the computer to:

obtain a 3D digital model of the patient'"'"'s dentition;

create a cutting surface representing an interproximal margin between adjacent teeth in the patient'"'"'s dentition and a surface that represents a tooth root, as to separate portions of the digital model representing the adjacent teeth; and

generate one or more appliances used in treating the patient based on the separated dentition model.

10. The program of claim 9, wherein the computer displays 2D cross sections of the digital model and receives input from a human operator identifying approximate points at which the interproximal margin between the adjacent teeth meets gingival tissue.

11. The program of claim 10, wherein the dentition model includes a 3D volumetric model of the patient'"'"'s digital and the input from the human operator identifies two voxels in 10 volumetric model.

12. The program of claim 11, wherein the computer defines a neighborhood of voxels around each of the two voxels identified by the human operator, where each neighborhood includes voxels representing the digital model and voxels representing a background image.

13. The program of claim 12, wherein the computer automatically selects a pair of voxels, both representing the background image, that lie closest together, where each neighborhood contains one of the voxels.

14. The program of claim 11, wherein the computer automatically identifies voxels on another 2D cross section that represent the interproximal margin.

15. The program of claim 14, wherein, in automatically identifying voxels on another 2D cross section, the computer:

defines a neighborhood of voxels around each of the selected voxels, where each neighborhood includes voxels representing the digital model and voxels representing a background image;

projects the neighborhoods onto the other 2D cross section; and

selects two voxels in the projected neighborhoods that represent the interproximal 30 margin.

16. The program of claim 15, wherein, in selecting two voxels in the projected neighborhoods, the computer selects a pair of voxels, both representing the background image, that lie closest together, where each of the neighborhoods contains one of the voxels.

19. The method of claim 9, further comprising using the surface representing a tooth root to separate portions of the digital model representing the tooth roots from portions representing gingival tissue.

20. The method of claim 19, further comprising connecting the portions of the digital model representing the tooth root to the portion representing the tooth.