三种推磨牙方法的临床比较研究

Comparison study of three methods of distalization for maxillary molars

目的:比较三种临床常用推磨牙向远中方法的效果及其特点。方法:将24例患者随机等分成三组,分别采用不同的方法进行推磨牙向远中矫治。方法一采用头帽面弓推磨牙向远中;方法二采用J形钩作为口外支抗,口内主弓丝上辅以镍钛螺旋推簧推磨牙向远中;方法三采用口内Nance托加强支抗,镍钛螺旋推簧推磨牙向远中。结果:磨牙平均移动速度方法一为0.6mm/月,方法二1.5mm/月,方法三1.5mm/月;磨牙长轴向远中倾斜角度方法一为3.4°,方法二8.6°,方法三8.8°;上颌中切牙长轴方法一无变化,方法二2.4°,方法三2.2°;前牙覆盖方法一无变化,方法二增加了2.0mm,方法三增加了1.8mm。结论:三种方法都取得了推磨牙向远中的预期效果,但三者在疗程、磨牙移动速度、磨牙移动的形式以及支抗丧失情况等方面都有区别。

Objective To evaluate the effects and characters of three different means for maxillary molars distalization. Methods 24 patients were divided equally into three groups stochasticly,each of the groups were corrected by different methods.Group1 applied headgear and facebow to distalize maxillary molars;Group2 used Ni Ti coil springs and modified J hooks;Group3 was Ni Ti coil springs and intraoral palate-covering anchorage. Results The velocity of molar distalizing was 0.6mm per month in Group1,1.5mm per month in Group2 and 1.5mm per month in Group3. The distal tipping angle of molar was 3.4° in Group1, 8.6° in Group2 and 8.8 °in Group3.Maxillary central incisor has no labiolingual tipping in Group 1,but tipped 2.4°in Group2 and 2.2°in Group3 respectively. Overjet didn′t changed in Group1,but increased 2.0mm in Group2 and 1.8mm in Group3. Conclusion All of the methods successfully distalized maxillary molars to appropriate positions.The distinctions among the three methods include period of treatment, velocity of distalizing molars, movement forms and loss of anchorage, etc.