Method for automatic tooth type recognition from 3D scans

Patent metadata

Field	Value
Publication number	US-10032271-B2
Application number	US-201514965033-A
Country	US
Kind code	B2
Filing date	Dec 10, 2015
Priority date	Dec 10, 2015
Publication date	Jul 24, 2018
Grant date	Jul 24, 2018

Abstract

Methods for recognizing or identifying tooth types using digital 3D models of teeth. The methods include receiving a segmented digital 3D model of teeth and selecting a digital 3D model of a tooth from the segmented digital 3D model. An aggregation of the plurality of distinct features of the tooth is computed to generate a single feature describing the digital 3D model of the tooth. A type of the tooth is identified based upon the aggregation, which can include comparing the aggregation with features corresponding with known tooth types. The methods also include identifying a type of tooth, without segmenting it from an arch, based upon tooth widths and a location of the tooth within the arch.

First claim

The invention claimed is:

1. A computer-implemented method for identifying a tooth type, comprising steps of executed by a processor:
receiving a segmented digital 3D model of teeth within an arch, wherein each tooth within the arch is digitally separated from other teeth within the arch and an actual type of the tooth is not identified;
selecting a digital 3D model of a tooth from the segmented digital 3D model, the selected digital 3D model being associated with a plurality of distinct features;
computing an aggregation of the plurality of distinct features to generate a single feature describing the selected digital 3D model of the tooth; and
identifying a type of the selected digital 3D model of the tooth with a particular degree of accuracy of the actual type of the tooth based upon the aggregation.

2. The method of claim 1 , wherein the receiving step comprises receiving the digital 3D model of teeth with an identification of boundaries between the teeth within the arch.

3. The method of claim 1 , wherein the receiving step comprises receiving the digital 3D model of teeth with an identification of an approximation of boundaries between the teeth within the arch.

4. The method of claim 1 , wherein the selecting step comprises receiving the plurality of features along with the selected digital 3D model.

5. The method of claim 1 , wherein the selecting step comprises computing the plurality of features for the selected digital 3D model.

6. The method of claim 1 , further comprising, executed by the processor, storing the identified type and the digital 3D model of the tooth in an electronic library of tooth shapes.

7. The method of claim 1 , wherein the computing step includes generating a covariance matrix of vertex-wise features in the digital 3D model of the tooth having faces and vertices.

8. The method of claim 1 , wherein the identifying step includes comparing the aggregation to features corresponding with known tooth types.

9. The method of claim 1 , wherein the computing step comprises computing an average of the plurality of features.

10. The method of claim 1 , further comprising, executed by the processor, displaying in a user interface the tooth and the identified type for the tooth.

11. The method of claim 1 , further comprising, executed by the processor, receiving contextual information for the selected digital 3D model of the tooth and using the contextual information for adjusting the identified type of the selected digital 3D model of the tooth.

12. The method of claim 11 , further comprising, executed by the processor, using a location of the tooth within the arch as the contextual information.

13. The method of claim 11 , further comprising, executed by the processor, using predicted types of neighboring teeth within the arch with respect to the tooth as the contextual information.

14. The method of claim 1 , further comprising, executed by the processor, repeating the selecting, computing, and identifying steps for each tooth within the arch.

15. The method of claim 14 , further comprising, executed by the processor, displaying within a user interface the digital 3D model of teeth within the arch and numbers associated with each tooth within the arch, wherein the numbers are correlated with the identified types of each tooth within the arch.

Assignees

• 3M Innovative Properties Co

Inventors

• Somasundaram Guruprasad
• Sivalingam Ravishankar
• Ribnick Evan J
• Xu Kevin S
• Pachauri Deepti

Classifications

• A61C9/0053 Primary

  Optical means or methods, e.g. scanning the teeth by a laser or light beam · CPC title

• G06V30/19173

  Classification techniques · CPC title

• G06V10/764

  using classification, e.g. of video objects · CPC title

• G06T7/0012 Primary

  Biomedical image inspection · CPC title

• G06F18/24133

  Distances to prototypes · CPC title