Virtual fillers for virtual models of dental arches
A processing device determines two or more adjacent teeth in a virtual model, the two or more adjacent teeth include a first tooth adjacent to a second tooth in the virtual model. The processing device inserts a first virtual filler in the virtual model between the first tooth and the second tooth. The processing device selects points in the virtual model. A processing device transforms the plurality of points into a voxel volume comprising a plurality of voxels. A processing device performs a smoothing operation on the voxel volume. A processing device subsequent to performing the smoothing operation on the voxel volume, determines a geometry of an updated virtual filler by transforming a surface of the smoothed voxel volume into a polygonal mesh.
1. A method for generating a virtual filler for design of an orthodontic aligner, comprising:
determining two or more adjacent teeth in a virtual model, the two or more adjacent teeth comprising a first tooth adjacent to a second tooth in the virtual model;
inserting a first virtual filler in the virtual model between the first tooth and the second tooth;
selecting a plurality of points in the virtual model, the plurality of points comprising first points on a surface of the first tooth, second points on a surface of the second tooth, third points on a surface of gingiva, and fourth points on the first virtual filler;
transforming the plurality of points into a voxel volume comprising a plurality of voxels;
performing a smoothing operation on the voxel volume; and
subsequent to performing the smoothing operation on the voxel volume, determining, by a processing device, a geometry of an updated virtual filler by transforming a surface of the smoothed voxel volume into a polygonal mesh.
2. The method of claim 1 , wherein:
selecting the first points on the surface of the first tooth comprises selecting points on the surface of the first tooth that are within a threshold distance from at least one of the first virtual filler or the surface of the second tooth; and
selecting the third points on the surface of the gingiva comprises selecting points on the surface of the gingiva that are within the a threshold distance of the first virtual filler.
3. The method of claim 1 , wherein performing the smoothing operation on the voxel volume comprises:
inflating the voxel volume by a first distance field offset to generate an inflated voxel volume;
transforming a surface of the inflated voxel volume into an inflated polygonal mesh;
transforming the inflated polygonal mesh into an intermediate voxel volume; and
deflating the intermediate voxel volume by a second distance field offset to generate the smoothed voxel volume.
4. The method of claim 3 , wherein the second distance field offset is greater than the first distance field offset.
5. The method of claim 1 , wherein determining the two or more adjacent teeth in the virtual model comprises:
determining that the two or more adjacent teeth comprise at least three adjacent teeth in the virtual model that satisfy a crowding criterion indicative of an amount of overlap between the teeth, wherein the at least three adjacent teeth comprise the first tooth, the second tooth, and a third tooth.
6. The method of claim 5 , further comprising:
inserting a second virtual filler in the virtual model between the first tooth and the third tooth; and
inserting a third virtual filler in the virtual model between the second tooth and the third tooth, wherein the plurality of points in the virtual model further comprise fifth points on a surface of the third tooth, sixth points on the second virtual filler, and seventh points on the third virtual filler.
7. The method of claim 1 , wherein the first virtual filler in the virtual model inserted between the first tooth and the second tooth is a virtual filler of a predetermined shape, wherein the first virtual filler comprises a first side and a second side, the first side of the first virtual filler located within the first tooth, the second side of the first virtual filler located within the second tooth.
8. The method of claim 1 , wherein the virtual model is a virtual model of a dental arch, the method further comprising:
updating the virtual model to include the updated virtual filler based on the determined geometry.
9. The method of claim 8 , further comprising:
fabricating a physical mold of the dental arch using the updated virtual model, wherein the physical mold comprises material in an area of the updated virtual filler.
10. A system for generating a virtual filler for design of an orthodontic aligner, comprising:
a memory device; and
a processing device operatively coupled to the memory device, the processing device to:
determine two or more adjacent teeth in a virtual model, the two or more adjacent teeth comprising a first tooth adjacent to a second tooth in the virtual model;
insert a first virtual filler in the virtual model between the first tooth and the second tooth;
select a plurality of points in the virtual model, the plurality of points comprising first points on a surface of the first tooth, second points on a surface of the second tooth, third points on a surface of gingiva, and fourth points on the first virtual filler;
transform the plurality of points into a voxel volume comprising a plurality of voxels;
perform a smoothing operation on the voxel volume; and
subsequent to performing the smoothing operation on the voxel volume, determine a geometry of an updated virtual filler by transforming a surface of the smoothed voxel volume into a polygonal mesh.
11. The system of claim 10 , wherein:
to select the first points on the surface of the first tooth, the processing device to select points on the surface of the first tooth that are within a threshold distance from at least one of the first virtual filler or the surface of the second tooth; and
to select the third points on the surface of the gingiva, the processing device to selecting points on the surface of the gingiva that are within the a threshold distance of the first virtual filler.
12. The system of claim 10 , wherein to perform the smoothing operation on the voxel volume the processing device to:
inflate the voxel volume by a first distance field offset to generate an inflated voxel volume;
transform a surface of the inflated voxel volume into an inflated polygonal mesh;
transform the inflated polygonal mesh into an intermediate voxel volume; and
deflate the intermediate voxel volume by a second distance field offset to generate the smoothed voxel volume.
13. The system of claim 10 , wherein to determine the two or more adjacent teeth in the virtual model, the processing device to:
determine that the two or more adjacent teeth comprise at least three adjacent teeth in the virtual model that satisfy a crowding criterion indicative of an amount of overlap between the teeth, wherein the at least three adjacent teeth comprise the first tooth, the second tooth, and a third tooth.
14. The system of claim 13 , the processing device further to:
insert a second virtual filler in the virtual model between the first tooth and the third tooth; and
insert a third virtual filler in the virtual model between the second tooth and the third tooth, wherein the plurality of points in the virtual model further comprise fifth points on a surface of the third tooth, sixth points on the second virtual filler, and seventh points on the third virtual filler.
15. The system of claim 10 , wherein the first virtual filler in the virtual model inserted between the first tooth and the second tooth is a virtual filler of a predetermined shape, wherein the first virtual filler comprises a first side and a second side, the first side of the first virtual filler located within the first tooth, the second side of the first virtual filler located within the second tooth.
16. A non-transitory computer-readable medium comprising instructions for generating a virtual filler for design of an orthodontic aligner that, responsive to execution by a processing device, cause a processing device to perform operations comprising:
determining two or more adjacent teeth in a virtual model, the two or more adjacent teeth comprising a first tooth adjacent to a second tooth in the virtual model;
inserting a first virtual filler in the virtual model between the first tooth and the second tooth;
selecting a plurality of points in the virtual model, the plurality of points comprising first points on a surface of the first tooth, second points on a surface of the second tooth, third points on a surface of gingiva, and fourth points on the first virtual filler;
transforming the plurality of points into a voxel volume comprising a plurality of voxels;
performing a smoothing operation on the voxel volume; and
subsequent to performing the smoothing operation on the voxel volume, determining, by the processing device, a geometry of an updated virtual filler by transforming a surface of the smoothed voxel volume into a polygonal mesh.
17. The non-transitory computer-readable medium of claim 16 , wherein:
selecting the first points on the surface of the first tooth comprises selecting points on the surface of the first tooth that are within a threshold distance from at least one of the first virtual filler or the surface of the second tooth; and
selecting the third points on the surface of the gingiva comprises selecting points on the surface of the gingiva that are within the a threshold distance of the first virtual filler.
18. The non-transitory computer-readable medium of claim 16 , wherein performing the smoothing operation on the voxel volume comprises:
inflating the voxel volume by a first distance field offset to generate an inflated voxel volume;
transforming a surface of the inflated voxel volume into an inflated polygonal mesh;
transforming the inflated polygonal mesh into an intermediate voxel volume; and
deflating the intermediate voxel volume by a second distance field offset to generate the smoothed voxel volume.
19. The non-transitory computer-readable medium of claim 16 , wherein determining the two or more adjacent teeth in the virtual model comprises:
determining that the two or more adjacent teeth comprise at least three adjacent teeth in the virtual model that satisfy a crowding criterion indicative of an amount of overlap between the teeth, wherein the at least three adjacent teeth comprise the first tooth, the second tooth, and a third tooth.
20. The non-transitory computer-readable medium of claim 19 , further comprising:
inserting a second virtual filler in the virtual model between the first tooth and the third tooth; and
inserting a third virtual filler in the virtual model between the second tooth and the third tooth, wherein the plurality of points in the virtual model further comprise fifth points on a surface of the third tooth, sixth points on the second virtual filler, and seventh points on the third virtual filler.