Granted Patent B2

US 12,370,014 · App. 17/347,300 · Granted Jul 29, 2025

Inventors: Vadim Matov (San Jose, CA); Jihua Cheng (San Jose, CA); Fuming Wu (Pleasanton, CA); Kenji Tan (Mountain House, CA)

Assignee: Align Technology, Inc.

A61C7/002G06F17/11G06F30/20G06T17/20G06T2210/12G06T2210/41

Abstract

Claims (56)

1. A non-transitory computing device readable medium having executable instructions which can be executed by a processor to cause a computing device to perform a method, comprising:

determining a bounding box of a mesh of a tooth of a dentition, the mesh including a plurality of triangles;

building a two-dimensional (2D) height map array for storing height values of a crown surface of the tooth, the crown surface corresponding to an area of the tooth that is visible or that is located above a gum-line;

determining which triangles of the plurality of triangles of the mesh are not backside triangles, wherein a backside triangle has a normal at more than a 90 degree angle with respect to a Z-axis direction;

scanning the triangles determined as not backside triangles to calculate corresponding height values and entering the height values into the 2D height map array;

constructing a virtual three-dimensional (3D) occlusogram based on the height values and occlusal distance values of the tooth, wherein the occlusal distance values are determined based on a 3D array corresponding to a 3D grid with generators defined by the bounding box of the mesh of the tooth;

attaching the virtual 3D occlusogram to a virtual 3D model of the tooth by associating the occlusal distance values of the tooth with the virtual 3D model of the tooth;

changing a position of the virtual 3D model of the tooth; and

updating the 3D occlusogram in response to the change of position of the virtual 3D model of the tooth, wherein updating the 3D occlusogram includes finding related teeth in the dentition effected by the change of position and recalculating the 3D occlusogram for the tooth and the related teeth.

2. The non-transitory computing device readable medium of claim 1 , wherein the bounding box is the smallest box created on the 2D grid that fully surrounds a projection of a triangle onto the 2D grid.

3. The non-transitory computing device readable medium of claim 1 , wherein scanning the triangles comprises determining whether more triangles remain as part of the mesh and scanning any remaining triangles.

4. The non-transitory computing device readable medium of claim 1 , further comprising:

entering height values for each tooth of an upper jaw and a lower jaw into the 2D height map array; and

determining a potential occlusion tooth list for each tooth of the upper jaw and the lower jaw.

5. The non-transitory computing device readable medium of claim 1 , further comprising:

initializing a closest distance component to a value of a height of a corresponding node of the 3D grid for all elements of the 3D array; and

scanning each polygon of a plurality of polygons of the tooth.

6. The non-transitory computing device readable medium of claim 1 , further comprising, for each triangle determined as not being a backside triangle:

computing a circumscribed sphere S of the triangle; and

forming a list of indices in a 3D array such that for every index a distance from a corresponding 3D grid node to a center of the sphere S is not greater than a sum of a radius of the sphere S and a current value of a closest distance component of an element of 3D array.

7. The non-transitory computing device readable medium of claim 6 , further comprising, for each triangle determined as not being a backside triangle:

(a) for each index in the list of indices, compute the distance from the corresponding 3D grid node to the triangle;

(b) set a closest distance to the computed distance and coordinates of a closest point to coordinates of a closest point computed on step (a).

8. The non-transitory computing device readable medium of claim 1 , further comprising:

determining occlusal distance values for posterior teeth using the 2D height map array, and

determining occlusal distance values for anterior teeth using distance fields.

9. The non-transitory computing device readable medium of claim 1 , wherein finding the related teeth of the dentition effected by the change of position includes finding teeth in upper and lower jaws of the dentition effected by the change of position.

10. The non-transitory computing device readable medium of claim 1 , wherein the 3D occlusogram is updated in response a user changing the position of the virtual 3D model of the tooth.

11. The non-transitory computing device readable medium of claim 10 , wherein the updated 3D occlusogram is viewable by the user in real-time.

12. The non-transitory computing device readable medium of claim 1 , wherein the 3D occlusogram is updated at each stage of multiple stage treatment plan.

13. The non-transitory computing device readable medium of claim 1 , wherein the 3D occlusogram is added via an add-on module for simulation and dental treatment CAD (Computing device Aided Design) programs.

14. A method, comprising:

determining a bounding box of a mesh of a tooth of a dentition, the mesh including a plurality of triangles;

building a two-dimensional (2D) height map array for storing height values of a crown surface of the tooth, the crown surface corresponding to an area of the tooth that is visible or that is located above a gum-line;

determining which triangles of the plurality of triangles of the mesh are not backside triangles, wherein a backside triangle has a normal at more than a 90 degree angle with respect to a Z-axis direction;

scanning the triangles determined as not backside triangles to calculate corresponding height values and entering the height values into the 2D height map array;

constructing a virtual three-dimensional (3D) occlusogram based on the height values and occlusal distance values of the tooth, wherein the occlusal distance values are determined based on a 3D array corresponding to a 3D grid with generators defined by the bounding box of the mesh of the tooth;

attaching the virtual 3D occlusogram to a virtual 3D model of the tooth by associating the occlusal distance values of the tooth with the virtual 3D model of the tooth;

changing a position of the virtual 3D model of the tooth; and

updating the virtual 3D occlusogram in response to the change of position of the virtual 3D model of the tooth, wherein updating the virtual 3D occlusogram includes finding related teeth in upper and lower jaws of the dentition effected by the change of position and recalculating the virtual 3D occlusogram for the tooth and the related teeth.

15. The method of claim 14 , further comprising determining a potential occlusion tooth list for each tooth of the upper and lower jaws, wherein the potential occlusion tooth list includes a listing of teeth that contact by occlusion.

16. The method of claim 15 , wherein determining the potential occlusion tooth list comprises determining which teeth having a bounding box that overlaps with the bound box of the mesh of the tooth.

17. The method of claim 14 , wherein the occlusal distance values for the tooth is determined based on a space or a collision depth between the related teeth of the upper and lower jaws.

18. The method of claim 14 , wherein the bounding box is the smallest box created on the 2D grid that fully surrounds a projection of a triangle onto the 2D grid.

19. A computing system, comprising:

a memory having executable instructions stored thereon; and

a processor coupled to the memory and configured to execute the instructions to:

determining a bounding box of a mesh of a tooth of a dentition, the mesh including a plurality of triangles;

building a two-dimensional (2D) height map array for storing height values of a crown surface of the tooth, the crown surface corresponding to an area of the tooth that is visible or that is located above a gum-line;

determining which triangles of the plurality of triangles of the mesh are not backside triangles, wherein a backside triangle has a normal at more than a 90 degree angle with respect to a Z-axis direction;

scanning the triangles determined as not backside triangles to calculate corresponding height values and entering the height values into the 2D height map array;

constructing a virtual three-dimensional (3D) occlusogram based on the height values and occlusal distance values of the tooth, wherein the occlusal distance values are determined based on a 3D array corresponding to a 3D grid with generators defined by the bounding box of the mesh of the tooth;

attaching the virtual 3D occlusogram to a virtual 3D model of the tooth by associating the occlusal distance values of the tooth with the virtual 3D model of the tooth;

changing a position of the virtual 3D model of the tooth; and

updating the virtual 3D occlusogram in response to the change of position of the virtual 3D model of the tooth, wherein updating the virtual 3D occlusogram includes finding related teeth in the dentition effected by the change of position and recalculating the virtual 3D occlusogram for the tooth and the related teeth.

20. The computing system of claim 19 , wherein the bounding box is the smallest box created on the 2D grid that fully surrounds a projection of a triangle onto the 2D grid.

Assignments (1)

Continuity (5)

References Cited (94)