腭中缝快速扩展前后下颌骨位置三维变化的螺旋CT测量研究

Study of mandible's three-dimensional effects of rapid maxillary expansion using spiral CT

目的使用螺旋CT观察在上颌骨快速扩展(RME)前后下颌骨位置在三维方向上的变化.方法使用螺旋CT观测10例恒牙(牙合)早期患者扩弓前后下颌骨各标志点间位置和角度改变.结果RME治疗后,下颌骨在前后向位置无明显改变;在垂直向向下移动并且有顺时针旋转的趋势.在水平向下颌骨有向非反(牙合)侧移动的趋势,下颌骨后部较前部移动更明显.结论下颌骨位置在RME前后在矢状向,垂直向和水平向三个方向均发生了相应的改变.使用螺旋CT可以对这种三维位置变化进行详细研究.

Objective To observe the mandible＇ s three-dimensional effects ot rapid maxauary expansion（RME） using spiral CT. Methods 10 cases of RME patiem were observed using spiral CT and a three-dimensional reference frame was set up to compare the position and angle changes of mandible. Results Mandible was not moved in anterior-posterior direction. And the foreside of mandible was not found moving horizontally, but the rearward of mandible displaced a little to the non-crossbite side after the crossbite correction on the crossbite side. The tendency of downward displacement in the foreside and bodily clockwise rotation of mandible existed. Conclusion Mandible moved and rotated in three-dimension after RME treatment. Spiral CT can be used in the study of three-dimension changes of orthodontics research.