Historical scan reference for intraoral scans

Patent metadata

Field	Value
Publication number	US-10136972-B2
Application number	US-201615199437-A
Country	US
Kind code	B2
Filing date	Jun 30, 2016
Priority date	Jun 30, 2016
Publication date	Nov 27, 2018
Grant date	Nov 27, 2018

Abstract

During an intraoral scan session, a processing device receives a plurality of intraoral images of a dental site. The processing device determines that a historical template of the dental site is existent and registers a first intraoral image of the plurality of intraoral images to the historical template at a first region of the dental site depicted in the historical template. The processing device may register one or more remaining intraoral images of the plurality of intraoral images to the historical template at a second region of the dental site depicted in the historical template. The first region may be separated from the second region.

First claim

What is claimed is:

1. A method comprising:
receiving, by a processing device, a plurality of intraoral images of a dental site during an intraoral scan session;
determining, by the processing device, that a first intraoral image of the plurality of intraoral images does not satisfy a registration criterion with regards to any other intraoral oral image of the plurality of intraoral images;
determining, by the processing device, that a historical template of the dental site is existent, wherein the historical template is a virtual model of the dental site as generated from additional intraoral images taken during a previous intraoral scan session;
registering, by the processing device, the first intraoral image to one or more remaining intraoral images of the plurality of intraoral images in a three-dimensional space according to the historical template, wherein the first intraoral image is associated with a first region of the dental site that does not overlap with a second region of the dental site associated with the one or more remaining intraoral images;
generating a first surface of the first region based on the first intraoral image;
generating a second surface of the second region based on the one or more remaining intraoral images; and
displaying, by the processing device, relative positions and orientations of the first surface and the second surface, wherein the historical template is not displayed.

2. The method of claim 1 , further comprising:
registering the first intraoral image to the historical template at the first region of the dental site; and
registering the one or more remaining intraoral images of the plurality of intraoral images to the historical template at the second region of the dental site.

3. The method of claim 2 , wherein the first intraoral image is registered to the historical template using first registration criteria and wherein the one or more remaining intraoral images are registered to the historical template using the first registration criteria, the method further comprising:
performing registration between the one or more remaining intraoral images using second registration criteria, wherein the second registration criteria are more restrictive than the first registration criteria.

4. A method comprising:
receiving, by a processing device, a plurality of intraoral images of a dental site during an intraoral scan session;
determining, by the processing device, that a first intraoral image of the plurality of intraoral images does not satisfy a registration criterion with respect to any other intraoral image of the plurality of intraoral images;
determining, by the processing device, that a historical template of the dental site is existent, wherein the historical template is a virtual model of the dental site as generated from additional intraoral images taken during a previous intraoral scan session; and
registering, the by processing device, the first intraoral image of the plurality of intraoral images to one or more remaining intraoral images of the plurality of intraoral images in a three-dimensional space according to the historical template, wherein the first intraoral image is associated with a first region of the dental site that does not overlap with a second region of the dental site associated with the one or more remaining intraoral images.

5. The method of claim 4 , further comprising:
generating, by the processing device during the intraoral scan session, a representation of the dental site comprising the first intraoral image at the first region and the one or more remaining intraoral images at the second region, wherein the representation is to be displayed on a graphical user interface (GUI).

6. The method of claim 5 , wherein the first intraoral image defines a first surface of the dental site at the first region and the one or more remaining intraoral images define a second surface of the dental site at the second region, the method further comprising:
determining a third surface of the dental site at a third region based on the historical template, wherein the third region is between the first region and the second region and overlaps with the first region and the second region; and
including the third surface in the representation.

7. The method of claim 4 , further comprising:
determining an intraoral area of interest based on the plurality of intraoral images and the historical template, wherein the intraoral area of interest comprises a third region of the dental site that is represented in the historical template but is not represented in the plurality of intraoral images; and
providing an indication of the intraoral area of interest.

8. The method of claim 4 , further comprising:
comparing the plurality of intraoral images to the historical template;
determining a difference between a previous depiction of the dental site as represented in the historical template and a current depiction of the dental site as represented in the plurality of intraoral images; and
generating a graphical representation of the difference between the previous depiction of the dental site and the current depiction of the dental site.

9. The method of claim 4 , wherein determining that the first intraoral image does not satisfy the registration criterion with respect to any other intraoral image of the plurality of intraoral images comprises determining that the first intraoral image does not overlap with the one or more remaining intraoral images.

10. The method of claim 4 , further comprising:
identifying a restorative area of the dental site represented in the plurality of intraoral images, wherein the restorative area comprises a stump of a tooth;
determining a baseline area associated with the restorative area based on the historical template, wherein the baseline area represents a surface of the tooth before the tooth was ground into the stump; and
providing the baseline area to be displayed in a graphical user interface.

11. The method of claim 4 , further comprising:
receiving an additional intraoral image during the intraoral scan session;
determining that the additional intraoral image is for a third region of the dental site between the first region and the second region;
registering the additional intraoral image to the first intraoral image; and
registering the additional intraoral image to at least one intraoral image of the remaining intraoral images.

12. The method of claim 4 , further comprising:
generating a three dimensional virtual model of the dental site from the plurality of intraoral images;
determining that a portion of the plurality of intraoral images represents soft tissue based at least in part on a difference between a previous depiction of the dental site as represented in the historical template and a current depiction of the dental site as represented in the plurality of intraoral images; and
removing the portion of the plurality of intraoral images that represents the soft tissue from the three dimensional virtual model of the dental site.

13. The method of claim 4 , wherein registering the first intraoral image to the one or more remaining intraoral images in the three-dimensional space according to the historical template comprises:
registering the first intraoral image to the historical template at the first region of the dental site using first registration criteria; and
registering the one or more remaining intraoral images to the historical template at the second region of the dental site using the first registration criteria.

14. The method of claim 13 , further comprising:
performing registration between

Assignees

• Align Technology Inc

Inventors

• Sabina Michael
• Rasovsky Leon

Classifications

• G06T7/30

  Determination of transform parameters for the alignment of images, i.e. image registration · CPC title

• G06T7/11

  Region-based segmentation · CPC title

• A61C13/0004 Primary

  Computer-assisted sizing or machining of dental prostheses · CPC title

• G06T17/00

  Three-dimensional [3D] modelling for computer graphics · CPC title

• A61C9/0053

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