Rapid prototyped transfer tray for orthodontic appliances

Patent metadata

Field	Value
Publication number	US-9763750-B2
Application number	US-201514820032-A
Country	US
Kind code	B2
Filing date	Aug 6, 2015
Priority date	Jun 26, 2008
Publication date	Sep 19, 2017
Grant date	Sep 19, 2017

Abstract

The present invention is directed to computer-implemented methods of making a transfer tray using rapid prototyping techniques, where the gingival edge of the tray is defined to intersect with at least one receptacle for receiving an orthodontic appliance. This tray configuration helps to minimize the travel distance of the tray when placing the tray over a patient's teeth, while also preserving a high degree of mechanical retention for retaining the appliance until such time that the appliance is bonded to the tooth. Other aspects of the tray and associated methods of bonding are directed to a frangible web that extends over the gingival portion of the receptacle and fractures to facilitate tray removal after bonding.

First claim

The invention claimed is:

1. A method of making a transfer tray for bonding an orthodontic appliance comprising:
obtaining a virtual model of a patient's dental structure;
determining a desired location for one or more virtual orthodontic appliances on the model;
providing a virtual receptacle at the desired location for each appliance of the one or more virtual orthodontic appliances, wherein each virtual receptacle has a configuration that matches at least a portion of the corresponding virtual orthodontic appliance;
deriving a virtual tray body extending across at least a portion of the model and at least a portion of each virtual receptacle remote from the model, wherein the act of deriving a virtual tray body includes the act of trimming the tray to create a gingival edge of the tray body that intersects each virtual receptacle; and
forming the transfer tray, wherein the transfer tray includes a physical tray body and one or more physical receptacles that correspond to the virtual tray body and virtual receptacles respectively, each physical receptacle sufficient to releasably retain a physical orthodontic appliance corresponding to the virtual appliance,
whereby when the physical appliance is retained in the physical receptacle, such appliance will include first facially oriented surfaces that extend below the gingival edge of the tray body and second facially oriented surfaces of the appliance that extend an occlusal direction from the gingival edge of the tray body, wherein all the second surfaces are enclosed by a portion of the tray body extending continuously across the physical receptacle and the first surfaces are not enclosed by any portion of the tray body.

2. The method of claim 1 , wherein the act of trimming the tray to create the gingival edge of the tray body comprises creating a cutting surface that intersects each the receptacle and virtually removing a portion of the tray body that is located in the gingival direction from the cutting surface.

3. The method of claim 1 , further comprising rendering a virtual stop member that connects to the tray body and matches at least a portion of the virtual model, wherein the transfer tray further includes a physical stop member that corresponds to the virtual stop member and wherein the physical tray body has a first Shore hardness and the physical stop member has a second Shore hardness that is greater than the first Shore hardness.

4. The method of claim 3 , wherein the virtual stop member includes a posterior section that matches a portion of a molar tooth and an anterior section that matches a portion of an anterior tooth, and wherein the virtual stop member further includes a flexible section that connects the posterior section and anterior section to each other.

5. The method of claim 3 , wherein the physical receptacle is adjacent to a region of material of the physical tray body having a third Shore hardness that is less than the first Shore hardness.

6. The method of claim 1 , further comprising placing an orthodontic appliance in the physical receptacle.

7. The method of claim 1 , wherein the physical receptacle is open-ended in a generally gingival direction to facilitate occlusal detachment of the transfer tray from the corresponding physical orthodontic appliance.

8. The method of claim 1 , wherein the virtual tray body further includes a virtual frangible web that extends across at least a portion of the gingival side of at least one virtual receptacle.

9. The method of claim 1 , wherein the act of determining a desired location for one or more virtual orthodontic appliances on the model comprises determining a desired location for a plurality of virtual orthodontic appliances on the model.

10. The method of claim 1 , wherein the gingival edge generally rises and falls based on the occlusal-gingival positions of three or more appliances along the dental arch.

11. The method of claim 1 , wherein at least one orthodontic appliance includes a custom base, and wherein the custom base has a configuration that matches the virtual model when the appliance is in the desired location.

12. The method of claim 1 , further comprising decreasing the size of at least one of the virtual receptacles in at least one dimension such that the virtual receptacle has a configuration that presents an interference fit in relation to the corresponding virtual appliance.

13. The method of claim 1 , wherein forming the transfer tray comprises forming the tray by rapid prototyping.

14. A method of bonding an orthodontic appliance to a patient's dental structure comprising:
obtaining a virtual model of a patient's dental structure;
determining desired locations for a plurality of virtual orthodontic appliance on the model;
providing a virtual receptacle at each desired location, wherein each virtual receptacle has a configuration that matches at least a portion of one of the appliances;
deriving a virtual tray body extending across at least a portion of the model and at least a portion of each receptacle remote from the model, wherein the act of deriving a virtual tray body includes the act of defining an gingival edge of the tray body that intersects each virtual receptacle so that, when an appliance is retained in each receptacle, all facially oriented surfaces of the appliance located in an occlusal direction from the gingival edge are enclosed by a portion of the tray body extending continuously across the receptacle;
forming the transfer tray, wherein the transfer tray includes a physical tray body and physical receptacles sufficient to releasably retain the appliances that correspond to the virtual tray body and virtual receptacles respectively;
placing the appliances in the physical receptacles, wherein a portion of each appliance placed extends below the gingival edge of the tray body and includes facially oriented surfaces that are not enclosed by any portion of the tray body;
applying an adhesive to the surface of the orthodontic appliances;
placing the transfer tray over the patient's dental structure; and
hardening the adhesive.

15. The method of claim 14 , further comprising detaching the transfer tray from at least one appliance by urging the transfer tray in a generally occlusal direction.

16. The method of claim 14 , wherein the physical tray body includes a frangible web that extends across at least a portion of the gingival side of at least one virtual receptacle, and further wherein the act of detaching the transfer tray from the appliance includes fracturing the frangible web.

17. The method of claim 14 , wherein forming the transfer tray comprises forming the tray by rapid prototyping.

Assignees

• 3M Innovative Properties Co

Inventors

• Kim Sung
• Raby Richard E

Classifications

• B29C64/00

  Additive manufacturing, i.e. manufacturing of three-dimensional [3D] objects by additive deposition, additive agglomeration or additive layering, e.g. by 3D printing, stereolithography or selective laser sintering · CPC title

• B29C64/386

  Data acquisition or data processing for additive manufacturing · CPC title

• B33Y50/00

  Data acquisition or data processing for additive manufacturing · CPC title

• B33Y10/00

  Processes of additive manufacturing · CPC title

• A61C7/146 Primary

  Positioning or placement of brackets; Tools therefor · CPC title