In fact 4 months post extraction and 3 months post retraction, the dental midlines remain unchanged, since no spaces have been created by themselves between U1s and between LR1-2 (Fig.7,8); power chains are extended mesially after arch wires are changed to 16x22.  The periodontal ligament between the neighboring teeth contributes to self drifting.  Place figure-8 wire between the posterior teeth as anchorage if anterior tooth shifting is required.

Midline Deviation Last Next

Xin Wei, DDS, PhD, MS 1st edition 08/04/2017, last revision 10/21/2018