System and method for detecting deviations during the course of an orthodontic treatment to gradually reposition teeth

• US 8,636,510 B2
• Filed: 11/10/2011
• Issued: 01/28/2014
• Est. Priority Date: 06/08/2007
• Status: Active Grant

• Current Assignee: Align Technology Incorporated
• Original Assignee: Align Technology Incorporated
• Inventors: Kitching, Ian, Cheang, Ka Man
• Primary Examiner(s): Rodriguez, Cris L
• Assistant Examiner(s): ROSEN, ERIC J
• Application Number:
  US13/293,916
• Publication Number:
  US 20120225401A1
• Time in Patent Office: 810 Days
• Field of Search: 433/24, 433/213, 433/214
• US Class Current: 433/24
• 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: G16H 50/50 for simulation or modelling of medical disorders
• CPC Class Codes: G16Z 99/00 Subject matter not provided for in other main groups of this subclass

Abstract

Method and system for detecting and correcting deviation during an orthodontic treatment plan is provided. The method includes the steps of receiving an un-segmented current teeth image representing a patient'"'"'s teeth after an orthodontic treatment plan has begun and before the plan ends for the patient; matching a previously segmented teeth model with the current teeth image; and generating at least one corrective stage to define an intermediate tooth arrangement, wherein the at least one corrective stage repositions a digital teeth image so that a prescribed tooth arrangement of the previously segmented teeth model can be used.

Claims

1. A method for detecting a deviation in a patient'"'"'s teeth during a planned orthodontic treatment for the patient, the method comprising:

receiving an un-segmented current teeth image representing a patient'"'"'s teeth after the planned orthodontic treatment has begun and before the planned orthodontic treatment ends;

pre-processing the un-segmented current teeth image so as to assign each of a plurality of teeth in the un-segmented current teeth image with a unique current teeth image identifier selected based on an anatomical feature of the respective tooth;

performing an initial comparison of the un-segmented current teeth image with a previously segmented teeth model by aligning each unique current teeth image identifier of the un-segmented current teeth image with a corresponding unique previously segmented model identifier assigned to a tooth of the previously segmented teeth model;

after performing the initial comparison of the un-segmented current teeth image with the previously segmented teeth model, determining a positional deviation between the un-segmented current teeth image and the previously segmented teeth model for each of one or more teeth in the previously segmented teeth model; and

generating a corrected stage model by using the determined one or more positional deviations to modify the previously segmented teeth model to reposition each of the one or more teeth in the previously segmented teeth model to match the un-segmented current teeth image.

2. The method of claim 1, wherein determining the one or more positional deviations includes creating a grid on the previously segmented teeth model, selecting sampling points on the previously segmented teeth model, and overlaying the grid on the un-segmented current teeth image.

3. The method of claim 2, wherein determining the one or more positional deviations comprises finding sampling points on the un-segmented current teeth image that are closest to the selected sampling points on the previously segmented teeth model.

4. The method of claim 2, wherein overlaying the grid on the un-segmented current teeth image includes superimposing the selected sampling points of the previously segmented teeth model onto the un-segmented current teeth image.

5. The method of claim 2, wherein creating the grid, selecting sampling points in the grid, and overlaying the grid on the un-segmented current teeth image are repeated until the previously segmented teeth model is within a preset tolerance from the un-segmented current teeth image.

6. The method of claim 1, wherein each tooth in the un-segmented current teeth image is individually assigned with the unique current teeth image identifier.

7. The method of claim 1, wherein the unique current teeth image identifier is a Facial Axis of a Clinical Crown (FACC) identifier, corresponds to an abnormality in a tooth in the un-segmented current teeth image, or corresponds to an attachment or marker on a tooth in the un-segmented current teeth image.

8. The method of claim 1, wherein the unique previously segmented model identifier is a Facial Axis of a Clinical Crown (FACC) identifier, corresponds to an abnormality in a tooth in the previously segmented teeth model, or corresponds to an attachment or marker on a tooth in the previously segmented teeth model.

9. The method of claim 1, comprising using the corrected stage model to create corrective stages from a tooth arrangement of the un-segmented current teeth image to a prescribed tooth arrangement.