PMC

Intraoral photographs under treatment. A: Lateral view of right side of intraoral pictures of the 4^th aligner; B: Frontal view of intraoral pictures of the 4^th aligner; C: Lateral view of left side of intraoral pictures of the 4^th aligner; D: Lateral view of right side of intraoral pictures of the 13^th aligner; E: Intraoral pictures of the 13^th aligner; F: Lateral view of left side of intraoral pictures of the 13^th aligner.

Quantification of variable aligner material on retention. (A) Vertical displacement forces (Newtons) of each aligner material during removal from the control cast containing no attachments. (B) Vertical displacement forces of each aligner material during removal from the cast containing ellipsoid attachments. (C) Vertical displacement forces of each aligner material during removal from the cast containing beveled attachments. Each column represents one of the tested aligner materials (CA soft, medium, hard; Essix ACE).

Quantification of variable attachments on retention. (A) CA soft aligner removal from three different casts containing either no attachments, ellipsoid, or beveled attachments. (B) CA medium aligner removal from three different casts containing either no attachments, ellipsoid, or beveled attachments (C) CA hard aligner removal from three different casts containing either no attachments, ellipsoid, or beveled attachments (D) Essix ACE aligner removal from three different casts containing either no attachments, ellipsoid, or beveled attachments.

Estimated and actual treatment durations. * = Actual treatment duration for Aligner group significantly longer than estimated p < 0.005. ** = Actual treatment duration for Aligner + HFA significantly shorter than estimated p < 0.001. # = Actual treatment duration for Aligner + HFA group significantly shorter than Aligner group, p < 0.001.