钟摆矫治器联合颊侧推簧远移磨牙的疗效分析

目的：评价钟摆矫治器联合颊侧推簧远移磨牙的疗效.方法：选择40例牙性安氏Ⅱ类错（牙合）畸形的患者,随机均分为两组：钟摆矫治器联合颊侧推簧远移磨牙组（组1）和头帽口外弓远移磨牙组（组2）,在治疗开始前（T0）和远移磨牙完成时（T1）分别拍摄侧位头影定位片进行头影测量,t检验分析组内和组间的差异.结果：组1和组2远移磨牙的平均距离分别是（4.48±1.63） mm、（2.68±1.71） mm;组1和组2磨牙远中倾斜的平均角度分别是5.46°±3.23°、1.02°±2.16°;组1上颌中切牙未发生明显的唇倾和唇向移位,而组2上颌中切牙发生了较为明显的腭侧移位.结论：钟摆矫治器联合颊侧推簧远移磨牙可有效防止前牙支抗的丧失、控制磨牙的近中颊侧旋转.

Efficiency of pendulum appliance supported with a Ni-Ti spring buccally for distalization of maxillary first molar

Objective： To evaluate the efficiency of pendulum appliance supported with a Ni-Ti spring buccally for distalization of maxillary first molars. Method： The experimental group comprised 40 dental Class II malocclusions subjects, divided into 2 groups randomly： group 1 consisted of 20 patients which were treated with the pendulum appliance supported with a Ni-Ti spring buccally： Patients in group 2 were treated with the cervical headgear. Cephalometric films were taken before the treatment （T0） and at the end of maxillary molars distalization （T1）. T0-T1 changes within and between the groups were analysed with a t-test. Result：The mean molar distalization was （4.48 ±1.63）mm in group 1 and （2.68±1.71）mm in group 2. In group 1 the mean distal tipping angle was 5.46°± 3.23° and in group 2 was 1.02°±2.16°. The protrusion and labi- al tipping of the upper incisors in groupl was not statistically significant, while the retrusion and palatal tipping of the upper incisors in group 2 was statistically significant. Conclusion： The pendulum appliance can distalize the upper molars effec- tively and decrease both the loss of anchorage at the anterior teeth and the amount of mesiobuccal rotation of the maxillary molars significantly.