Methods of forming dental tooth positioning appliances

1. A method of forming a dental tooth positioning appliance, the method comprising:

receiving a first digital model of a dentition;

identifying a portion of the first digital model corresponding to a portion of the dentition for chemical treatment;

forming a second digital model comprising one or more scaled up cavities, formed by scaling up a size of one or more teeth of the first digital model of the dentition, wherein the one or more teeth of the first digital model correspond to the portion of the first digital model identified for chemical treatment, the one or more scaled up cavities sized based on a particular type of chemical treatment; and

forming a polymeric shell having cavities shaped to receive the dentition, the polymeric shell including one or more scaled up cavities having dimensions that are proportional to a corresponding surface of the second digital model, wherein the polymeric shell further includes one or more spacers that protrude from an inner surface of the one or more scaled up cavities of the polymeric shell, wherein the one or more spacers of the polymeric shell are arranged to maintain a uniform space, corresponding to the scaled up size, between the polymeric shell and the portion of the dentition identified for chemical treatment, and for holding a chemical for treating the identified portion of the dentition.

2. The method of claim 1 , wherein the one or more spacers of the polymeric shell is arranged to contact the one or more teeth of the identified portion of the dentition positioned within the one or more scaled up cavities of the polymeric shell.

3. The method of claim 2 , wherein the one or more spacers of the polymeric shell is configured to offset the inner surface of the one or more scaled up cavities of the polymeric shell from the one or more teeth.

4. The method of claim 1 , wherein the dental tooth positioning appliance is configured to reposition at least one tooth of the dentition from a first configuration to a successive configuration.

5. The method of claim 1 , wherein the one or more teeth of the second digital model is scaled up by a first percentage, wherein the method further comprises scaling up a size of a second one or more teeth of the second digital model by a second percentage different than the first percentage.

6. The method of claim 1 , wherein forming the polymeric shell includes forming at least one fitted cavity having a shape and size to snuggly fit on at least one other tooth of the dentition.

7. The method of claim 6 , wherein the fitted cavity is configured to create a fixed orientation of the dental tooth positioning appliance with respect to the dentition.

8. The method of claim 1 , wherein scaling up the size of the one or more teeth of the first digital model includes proportionately increasing dimensions of the one or more teeth of the first digital model.

9. A method of forming a dental tooth positioning appliance, the method comprising:

receiving a first digital model of a dentition;

identifying a portion of the first digital model corresponding to the portion of the dentition for chemical treatment;

forming a second digital model comprising one or more scaled up cavities, formed by scaling up a size of one or more teeth of the first digital model, wherein the one or more teeth of the first digital model correspond to the portion of the first digital model identified for chemical treatment, the one or more scaled up cavities sized based on a particular type of chemical treatment; and

forming a polymeric shell having cavities shaped to receive the dentition, the polymeric shell configured to reposition at least one tooth of the dentition from a first configuration to a successive configuration, wherein the polymeric shell includes one or more scaled up cavities having dimensions that are proportional to a corresponding surface of the one or more scaled up cavities of the second digital model, wherein the polymeric shell further includes one or more spacers that protrude from an inner surface of the one or more scaled up cavities of the polymeric shell, wherein the one or more spacers of the polymeric shell are arranged to maintain a uniform space, corresponding to the scaled up size, between the polymeric shell and the portion of the dentition identified for chemical treatment, and for holding a chemical for treating the identified portion of the dentition.

10. The method of claim 9 , wherein the one or more spacers of the polymeric shell is arranged to contact the portion of the dentition identified for chemical treatment positioned within the one or more scaled up cavities of the polymeric shell.

11. The method of claim 9 , wherein the one or more spacers of the polymeric shell is configured to offset the inner surface of the one or more scaled up cavities of the polymeric shell from the portion of the dentition identified for chemical treatment.

12. The method of claim 9 , wherein forming the polymeric shell includes forming at least one fitted cavity having a shape and size to snuggly fit on at least one other tooth of the dentition.

13. The method of claim 12 , wherein the fitted cavity is configured to create a fixed orientation of the dental tooth positioning appliance with respect to the dentition.

14. The method of claim 9 , wherein scaling up the size of the one or more teeth of the first digital model includes proportionately increasing dimensions of the one or more teeth of the first digital model.

15. A method of forming a dental tooth positioning appliance, the method comprising:

receiving a first digital model of a dentition;

identifying one or more portions of the first digital model corresponding to one or more portions of the dentition for chemical treatment;

forming a second digital model comprising one or more scaled up cavities, formed by scaling up a size of one or more teeth of the first digital model of the dentition, wherein the one or more teeth of the first digital model correspond to the one or more portions of the first digital model identified for chemical treatment, the scaled up size based on a particular type of chemical treatment, wherein scaling up the size comprises uniformly increasing dimensions of the one or more teeth of the first digital model; and

forming a polymeric shell having cavities shaped to receive the dentition, the polymeric shell including one or more scaled up cavities corresponding to the one or more scaled up cavities of the second digital model, wherein the polymeric shell further includes one or more spacers that protrude from an inner surface of the one or more scaled up cavities of the polymeric shell, wherein the one or more spacers of the polymeric shell are arranged to maintain a uniform space, corresponding to the scaled up size, between the polymeric shell and the one or more portions of the dentition identified for chemical treatment, and for holding a chemical for treating the one or more portions of the dentition.

16. The method of claim 1 , wherein forming the second digital model of the one or more scaled up cavities comprises scaling up the size of the one or more teeth of the first digital model only in a buccal direction and/or a lingual direction.

17. The method of claim 1 , further comprising scaling up a size of a gingival area associated with the one or more teeth of the first digital model, wherein the gingival area of the first digital model corresponds to a gingival area of the portion of the dentition identified for chemical treatment.

18. The method of claim 15 , wherein the one or more spacers of the polymeric shell are arranged to contact the one or more portions of the dentition identified for chemical treatment.

19. The method of claim 15 , wherein forming the second digital model comprises scaling up the size of the one or more teeth of the first digital model only in a buccal direction and/or a lingual direction.