Systems and methods for designing, and improving retention of, orthodontic aligners

A removable orthodontic aligner that is configured to mate with and retentively sit adjacent to an undercut area of each of one or more teeth of a patient, wherein the removable orthodontic aligner is produced by:

• (a) operating a digital scanner to obtain a digital image of the patient's dentition;
• (b) operating a computing environment, which comprises a central processor, memory, imaging software, and a graphical user interface, to:
• (i) receive a copy of the digital image;
• (ii) create a reference plane relative to one or more teeth featured within the digital image;
• (iii) position a line that runs perpendicular from the reference plane and runs tangential to a height of maximum convexity of each of the one or more teeth;
• (iv) measure an area of undercut between such perpendicular line and an exterior surface of each of the one or more teeth;
• (v) repeat steps (i)-(iv) at a plurality of points along a perimeter of each of the one or more teeth;
• and
• (vi) construct a three-dimensional model that represents a compilation of each area of undercut calculated by the system for each of the one or more teeth;
• and
• (c) producing the removable orthodontic aligner to exhibit interior dimensions that are configured to mate with the undercut area for each of the one or more teeth depicted within the three-dimensional model and to retentively sit adjacent to the undercut area for each of the one or more teeth of the patient, wherein the removable orthodontic aligner further comprises one or more anti-relapse features, wherein the anti-relapse features are configured to discourage or prevent relapse movement of an underlying tooth.