Orthodontic appliances that accommodate incremental and continuous tooth movement, systems and methods

1. A method of computer aided design of a shell appliance geometry to implement at least a portion of a treatment plan, the method comprising:

receiving, with a computer, a first position of the at least one bracketed tooth in a treatment plan;

receiving, with the computer, a second position of the at least one bracketed tooth in the treatment plan different from the first position;

determining, with the computer, a movement path geometry comprising a volume accommodating (1) mesial-distal movement relative to an appliance shell of the at least one bracketed tooth between the first position and the second position, the mesial-distal movement being elicited by force applied by the wire and bracket appliance, and (2) rotational movement of the at least one bracketed tooth between the first position and the second position;

digitally generating, with the computer, the shell appliance geometry comprising (1) a plurality of teeth receiving cavities shaped according to the movement path geometry that accommodates the mesial-distal and rotational movements between the first and second positions to receive and resiliently position teeth of the patient and (2) a relief portion comprising a cavity defining a geometric volume encompassing at least a volume corresponding to a geometric summation of volumes occupied by the at least one bracketed tooth when following between the first position and the second position; and

fabricating the appliance shell having the shell appliance geometry based at least in part on the plurality of teeth receiving cavities and the relief portion.

2. The method of claim 1 , wherein the at least one bracket is disposed at least partially outside the relief portion when the at least one bracketed tooth is received within the cavity.

3. The method of claim 1 , wherein the relief portion defines an unobstructed insertion path for the at least one bracket when the appliance shell is at least one of: positioned on the patient's teeth or removed from the patient's teeth.

4. The method of claim 3 , wherein the relief portion comprises a shortened shell wall extending less than an entire distance between an occlusal portion of the at least one bracketed tooth and a gingival line of the at least one bracketed tooth when the at least one bracketed tooth is received within the cavity so as to provide the unobstructed insertion path for the at least one bracket.

5. The method of claim 4 , wherein the shortened shell wall extends partially over the at least one bracket when the at least one bracketed tooth is received within the cavity.

6. The method of claim 3 , wherein the relief portion comprises a cutout extending around the at least one bracket when the at least one bracketed tooth is received within the cavity so as to provide the unobstructed insertion path for the at least one bracket.

7. The method of claim 1 , wherein the volume is defined by the at least one bracketed tooth moving between a plurality of intermediate positions between the first position and the second position.

8. The method of claim 1 , wherein the relief portion is shaped to restrict at least one direction of movement of the at least one bracketed tooth during the mesial-distal movement of the at least one bracketed tooth between the first position and the second position.

9. The method of claim 1 , wherein the relief portion comprises an active portion that contacts the at least one bracketed tooth so as to apply a force to the at least one bracketed tooth.

10. The method of claim 1 , wherein the relief portion is shaped to accommodate a plurality of bracketed teeth each coupled to a respective bracket of the wire and bracket appliance.