Objective To observe the curative effect of treatment employing two-stage rectification method on the deformation of mandibular retrusion in dental transitional period. 目的观察用两期矫治方法治疗替牙期下颌后缩畸形。
Method Tractions of type ⅲ were performed for initial correction of 23 cases of cross bite in their dental transitional period or starting period of permanent teeth. 方法对23例换牙期、恒牙初期反牙合病例在其矫治初始阶段行Ⅲ类牵引。