快速扩弓结合前方牵引对牙颌作用的三维测量研究

目的探讨应用快速扩弓结合前方牵引矫治替牙期骨性Ⅲ类反在三维方向上的作用。方法选取30例替牙期骨性Ⅲ类反患者,应用快速扩弓结合前方牵引的方法进行治疗。分别对矫治前、后的X线头颅侧位片和石膏模型进行测量分析,并运用SPSS12.0软件进行统计学处理。结果快速扩弓结合前方牵引治疗替牙期骨性Ⅲ类反作用为:①水平方向上增加上颌牙弓宽度;②矢状方向上上颌突度的增加是上前牙唇倾,上颌骨向前生长的结果;下颌突度的减小是下颌后下旋转和髁突在关节窝内移位共同作用的结果;③垂直方向的变化与水平和矢状方向的变化密切相关,面下高度增加,下颌平面角增大。结论快速扩弓结合前方牵引治疗可有效矫正替牙期骨性Ⅲ类反,但使牙颌结构在三维方向上都产生极其复杂的不同的变化,应根据错的特点调整相应的治疗措施以使在各个方向上增加有利的变化,避免或减少不利的变化。

Study of dento-alveolar changes of patients after treatment of combination of rapid maxillary expansion and maxillary protraction through three dimensional measurement

Objective To study the response in three dimensional directions of Angel class Ⅲ patients in the mixed dentition phases after the treatment of the combination of rapid maxillary expansion and maxillary protraction. Methods Thirty skeletal class Ⅲ patients in the mixed dentition phases treated by combination of rapid maxillary expansion and maxillary protraction were selected. The lateral cephalometric records and dental cast were taken to assess the dentoalveolar changes before and after the treatment. SPSS 12.0 software package was used for pared t test. Results All Angle class Ⅲ malocclusions were corrected within 6 months. ①The arch width increased in the horizontal direction. ②The sagittal changes consisted of maxillary anterior displacement and mandibular posterior displacement achieved by lingual tipping of the mandibular incisors and mandibular rotation and posterior displacement of the condyle. ③ The vertical changes had relations with the changes in horizontal and sagittal directions. Conclusion The combination of rapid maxillary expansion and maxillary protraction was an effective appliance in the treatment of Angle class Ⅲ patients in the mixed dentition phases. But the changes in each direction were very complicated . Therefore, we should adjust the treatment measures according to the characteristics of different deformities to increase the favorable direction of change and to avoid or reduce the adverse changes.