[Objective] The external plate system to the palate was developed as a skeletal anchorage device, and named the Anchor-Lock. The aim of this study was to assess the effectiveness of the Anchor-Lock to distalize upper molars in three-dimensions.
[Methods] 12 adult patients (9 females and 3 males) participated in this study. Upper dental casts were measured in three-dimensions by 3D scanner, consequently surface dental models were reconstructed. To assess the distalization of molars in three-dimensions, the palatal region of interest (PRI) was setup. PRI of the pre and the post treatment were superimposed by using the iterative Closest Point method. Three-dimensional movements of the upper first molar were evaluated in the coordinate system defined by the occlusal plane.
[Results] High stability of PRI was demonstrated during orthodontic treatment. The average of distal movement of the upper first molar was 2.80mm (1.61～3.98 mm), buccal movement was 1.53mm (0.23～2.73 mm) and distal inclination was 1.83 degrees (- 3.6～9.04 degrees).
[Conclusions] The distalization of the upper molars was successfully accomplished by the Anchor-Lock.
*3D scanner (C Pro dental system, Panasonic Corporation)