传统式Twin-block矫治器与逐步式前移下颌的Twin-block矫治器治疗下颌后缩畸形的临床疗效评价

目的:比较传统的一次最大前伸法Twin-block矫治器与改良逐步式前移下颌的Twin-block矫治器治疗下颌后缩畸形的临床疗效。方法:选择处于替牙晚期或恒牙早期ANB角>5°,覆盖>6mm的骨性下颌后缩患者13例,接受逐步式前移下颌的TB矫治器治疗,根据病例对照的原则收集使用传统一步法TB矫治器治疗的病例13例作为对照组,应用X线头影测量技术进行治疗前后的18项硬组织测量分析。结果:逐步式TB矫治器治疗后 SNB角增大,Y轴角变小,下颌颏部相对颅底位置关系变化明显,MP-SN、FH-MP增大改善深覆牙合。两组矫治后磨牙调整为中性关系或轻度近中关系,前牙覆牙合覆盖基本正常;上下颌关系协调。结论:传统式Twin-block矫治器和逐步式Twin- block功能矫治器早期治疗安氏II类1分类下颌后缩患者,疗效基本相同,但改良式Twin-block矫治器患者戴用舒适度好,可优先考虑之。

Comparative Study of Curative Effectiveness of Mandibular Retrognathia Cases with Traditional Twin-block or Stepwise Twin-block Appliance.

Objective: To compare clinical curative effect on Class Ⅱ with mandibular retrognathia by the two Twin-block appliance. Methods: 13 mandibular retrusion case with mixed dentition or early permanent dentition were selected, they received modified Twin-block treatment. According to the case control principle 13 case with Twin-block treatment were selected as the control group .The Cephalometrics analysis was performed before and after treatment for oberserving 18 hard tissue variables. Results: In the experiment group, the SNB increased, the Y axis decreased, MP-SN, FH-MP increased, the jaw and chin position relative to the skull base of change was obvious .Early treatment with two Twin-block appliance were effective in overjet and correction. Conclusion: It was almost the same effect for Class II Division 1 mandibular retrusion patients using Twin block or modified Twin-block in the early treatment. But the modified Twin-block appliance was more suitable for curing Angle’s class II division 1 mandibular retrusion cases.