US 11,751,978 B2
Layered aligners with discontinuities
Avi Kopelman, Palo Alto, CA (US); and Jeeyoung Choi, Sunnyvale, CA (US)
Assigned to Align Technology, Inc., San Jose, CA (US)
Filed by Align Technology, Inc., San Jose, CA (US)
Filed on Oct. 22, 2021, as Appl. No. 17/508,880.
Application 17/508,880 is a continuation of application No. 14/610,060, filed on Jan. 30, 2015, granted, now 11,154,382.
Claims priority of provisional application 62/015,170, filed on Jun. 20, 2014.
Prior Publication US 2022/0039921 A1, Feb. 10, 2022
Int. Cl. A61C 7/08 (2006.01); A61C 7/00 (2006.01)
CPC A61C 7/08 (2013.01) [A61C 7/002 (2013.01); Y10T 29/4957 (2015.01); Y10T 83/04 (2015.04); Y10T 83/0586 (2015.04)] 26 Claims
OG exemplary drawing
 
1. An aligner comprising:
a polymeric shell comprising:
a plurality of tooth-receiving cavities shaped to receive a patient's teeth and reposition the patient's teeth from a first arrangement toward a second arrangement;
an interior layer comprising a first stiffness; and
an exterior layer comprising a second stiffness greater than the first stiffness, wherein the exterior layer comprises a discontinuity formed therein, and the discontinuity comprises a cut,
wherein, when the aligner is worn on the patient's teeth, the cut is stretched by placement of the aligner on the patient's teeth, the interior layer interacts with the cut by resisting the stretching, and the interaction between the interior layer and the cut imparts one or more forces to facilitate repositioning of the patient's teeth from the first arrangement toward the second arrangement.