Orthodontic aligner manufacturing and quality assessment system

Patent metadata

Field	Value
Publication number	US-12263620-B2
Application number	US-202217990581-A
Country	US
Kind code	B2
Filing date	Nov 18, 2022
Priority date	Nov 23, 2021
Publication date	Apr 1, 2025
Grant date	Apr 1, 2025

Abstract

Implementations describe systems and methods for manufacturing and performing quality assessment of dental appliances. In one embodiment, a method of manufacturing a dental appliance comprises receiving, at a holder, a feature of the dental appliance, the feature comprising a first surface having a first shape, wherein the holder holds the feature of the dental appliance at a reference position. The method further includes automatically placing an object against the feature at the reference position using a robot arm, wherein the object comprises a second surface having a second shape that mates with the first shape. The method further includes applying pressure to press the object against the feature of the dental appliance and bonding the object to the feature of the dental appliance while applying the pressure.

First claim

What is claimed is:

1. A method of manufacturing a dental appliance, comprising:
receiving, at a holder, a feature of the dental appliance, the feature comprising a first surface having a first shape, wherein the holder holds the feature of the dental appliance at a reference position;
capturing an image of the dental appliance in the holder prior to placing an object against the feature of the dental appliance;
processing the image;
determining whether the dental appliance has a correct placement in the holder based on a result of the processing;
automatically placing the object against the feature at the reference position using a robot arm, wherein the object comprises a second surface having a second shape that mates with the first shape;
applying pressure to press the object against the feature of the dental appliance; and
bonding the object to the feature of the dental appliance while applying the pressure.

2. The method of claim 1 , further comprising performing the following prior to receiving the feature of the dental appliance at the holder:
performing three-dimensional printing to print a mold for the dental appliance;
thermoforming the dental appliance over the mold;
trimming the dental appliance along a trim line; and
removing the dental appliance from the mold.

3. The method of claim 1 , wherein the dental appliance comprises an orthodontic aligner, the method further comprising performing the following before placing the object against the feature of the orthodontic aligner:
determining an aligner type of the orthodontic aligner;
determining an object type to use from a plurality of object types, wherein the object type is associated with the aligner type; and
automatically picking up the object having the object type using the robot arm.

4. The method of claim 3 , wherein determining the aligner type comprises:
capturing an image of the feature; and
processing the image.

5. The method of claim 4 , wherein:
the feature comprises a pattern of notches and/or protrusions associated with the aligner type, wherein processing of the image is performed to identify the pattern of notches and/or protrusions of the feature, and wherein the object having the object type comprises an opposing pattern of notches and/or protrusions that mates with the pattern of notches and/or protrusions of the feature for the aligner type.

6. The method of claim 1 , wherein processing the image comprises inputting the image into a trained machine learning model, wherein the trained machine learning model generates an output indicating whether the dental appliance has the correct placement in the holder.

7. The method of claim 1 , wherein bonding the object to the feature comprises laser welding the object to the feature.

8. The method of claim 7 , wherein the object comprises a layer of a photo-thermal compound on the second surface of the object, wherein at least one of a) the dental appliance is a clear plastic dental appliance or b) the object is a clear plastic object, and wherein performing the laser welding comprises:
directing coherent light having a first wavelength through at least one of the clear plastic dental appliance or the clear plastic object onto an interface of the first surface and the second surface, wherein the photo-thermal compound absorbs the coherent light having the first wavelength and generates heat that melts the object and the dental appliance at the interface of the first surface and the second surface.

9. The method of claim 7 , wherein the object comprises plastic impregnated with a photo-thermal compound, wherein the dental appliance is a clear plastic orthodontic aligner, and wherein performing the laser welding comprises:
directing coherent light having a first wavelength through the clear plastic orthodontic aligner onto an interface of the first surface and the second surface, wherein the photo-thermal compound at the second surface absorbs the coherent light having the first wavelength and generates heat that melts the object and the dental appliance at the interface of the first surface and the second surface.

10. A method of manufacturing an orthodontic aligner, comprising:
receiving, at a holder, a feature of the orthodontic aligner, the feature comprising a first surface having a first shape, wherein the holder holds the feature of the orthodontic aligner at a reference position;
determining an aligner type of the orthodontic aligner, wherein determining the aligner type comprises:
capturing an image of the feature; and
inputting the image into a trained machine learning model, wherein the trained machine learning model outputs a classification for the orthodontic aligner that indicates the aligner type;

determining an object type to use from a plurality of object types, wherein the object type is associated with the aligner type;
automatically picking up an object having the object type using a robot arm;
automatically placing the object against the feature at the reference position using the robot arm, wherein the object comprises a second surface having a second shape that mates with the first shape;
applying pressure to press the object against the feature of the orthodontic aligner; and
bonding the object to the feature of the orthodontic aligner while applying the pressure.

11. A method of manufacturing a dental appliance, comprising:
receiving, at a holder, a feature of the dental appliance, the feature comprising a first surface having a first shape, wherein the holder holds the feature of the dental appliance at a reference position;
automatically placing an object against the feature at the reference position using a robot arm, wherein the object comprises a second surface having a second shape that mates with the first shape;
capturing an image of the dental appliance in the holder prior to bonding the object to the dental appliance;
processing the image;
determining whether the object is correctly placed against the feature of the dental appliance based on a result of the processing;
applying pressure to press the object against the feature of the dental appliance; and
bonding the object to the feature of the dental appliance while applying the pressure.

12. The method of claim 11 , wherein processing the image comprises inputting the image into a trained machine learning model, wherein the trained machine learning model generates an output indicating at least one of a) whether the object was correctly placed against the feature of the dental appliance, or b) whether the object is a correct object type for placement against the feature of the dental appliance.

13. A method of manufacturing a dental appliance, comprising:
receiving, at a holder, a feature of the dental appliance, the feature comprising a first surface having a first shape, wherein the holder holds the feature of the dental appliance at a reference position;
automatically placing an object against the feature at the reference position using a robot arm, wherein the object comprises a second surface having a second shape that mates with the first shape;
measuring an amount of force applied to place the object against the feature of the dental appliance during the placing of the object against the feature of the dental appliance;
determining whether the amount of force is between an upper force threshold and a lower force threshold;
determining whether the object has been correctly placed against the feature of the dental appliance based on whether the amount of force is between the upper force threshold and the lower force threshold;
applying pressure to press the object against the feature of th

Assignees

• Align Technology Inc

Inventors

• Nishimuta James
• Soltero Borrego Enrique
• Guzman Olivas Enrique Jonathan
• Sato Jun
• Rodriguez Trujillo Kevin Daniel
• Blanco Romo Jose Kiyotaka
• Enriquez De Anda Erick
• Pickens Lance Robert
• Wong Wesly
• Perez Vallejo Gabriela
• Garcia Carmona Carlos Alberto
• Barraza Alvarez Omar
• Hurtado Soltero Miguel Angel

Classifications

• B33Y10/00

  Processes of additive manufacturing · CPC title

• A61C7/08

  Mouthpiece-type retainers {or positioners, e.g. for both the lower and upper arch (arch-shaped medicament applicators for teeth or gums A61C19/063; mouthguards for protecting the teeth of sportsmen A63B71/085)} · CPC title

• B33Y80/00

  Products made by additive manufacturing · CPC title

• B33Y50/00

  Data acquisition or data processing for additive manufacturing · CPC title

• B29L2031/753

  Medical equipment; Accessories therefor (bloodbags, medical bags B29L2031/7148; artificial eyes B29L2011/0008) · CPC title