下颌后缩畸形的联合功能矫治及固定矫治

Combination of Twin Block Appliance and Activator in Treatment of Mandibular Retrognathism Followed by Fixed Appliance

目的探讨第Ⅰ期采用双阻板矫治器(twin block appliance,TBA)联合肌激动器矫治生长发育期下颌后缩畸形,第Ⅱ期进行固定矫治的临床效果。方法1例下颌后缩的骨性Ⅱ类错患者,第Ⅰ期第1阶段采用TBA矫治,使上下颌骨呈骨性Ⅰ类关系;第2阶段采用肌激动器使后牙建。第Ⅱ期采用直丝弓矫治技术排齐牙齿、整平曲线、以及调整磨牙至中性关系并维持之。结果第Ⅰ期第1阶段,TBA矫治后下颌后缩得到纠正,上下颌骨呈骨性Ⅰ类关系,前牙覆盖变小,面型明显改善;第2阶段肌激动器可使后牙建良好,并能维持第1阶段达到的牙、颌关系;第Ⅱ期直丝弓矫治结束时牙齿排列整齐、曲线平整、磨牙呈中性关系。结论矫治下颌后缩畸形,TBA联合肌激动器较使用单一功能矫治器有明显的优势;必要时,应作Ⅱ期固定矫正。

Objective To evaluate the availability of Twin Block Appliance （TBA） combined with activator in correction of mandibular retrognathism. Methods A patient diagnosed as skeletal Class Ⅱ with mandibular retrognathism was treated by two-phase treatment. In the first stage of phase 1, TBA had been used until the horizontal discrepancy was corrected. In the second stage of phase 1, posterior occlusion was created by the application of activator. In phase 2, the straight wire appliance was used as supplement in order to align teeth, level curve of Spee, adjust and maintain the molar relationship. Results At the end of the first stage of phase 1, sagittal skeletal relationship changed to Class Ⅰ and man- dibular retrognathism was corrected; Anterior overjet reduced, while facial front view and profile were significantly amel- iorative. Normal posterior occlusion was created, skeletal and anterior teeth relationship that obtained in first phase was maintained by use of activator in the second stage of phase 1. At the end of phase 2, alignment of teeth, curve of Spee, anterior and posterior relationship were satisfying after SWA therapy. Conclusion The treatment method of using TBA combined with activator is recommended in correction of mandibular retrognathism, as compared with conventional single functional appliance. It is suggested that fixed appliance should be applied after functional appliance therapy.