Fig. 3From: Surface wear of attachments in patients during clear aligner therapy: a prospective clinical studyComparison of wear between three types of commonly used attachments. The wear volume (A), the ratio of wear volume (B), and the average wear depth (C) are shown throughout the follow-up period. * indicates P < 0.05; ** indicates P < 0.01; *** indicates P < 0.001Back to article page