上颌快速扩弓后牙及牙槽骨变化的锥束计算机断层扫描测量分析

Cone beam computed tomography analysis of teeth and alveolar bone changes after rapid maxillary expansion

目的 :使用锥束计算机断层扫描(cone beam computer tomography,CBCT)评价牙及牙槽骨在上颌快速扩弓后的变化。方法:需进行上颌快速扩弓的患者24例,在扩弓前和扩弓后拍摄CBCT作为临床资料,在CBCT上测量上颌第一前磨牙和上颌第一磨牙处的中央窝宽度,上颌第一磨牙的倾斜度,上颌第一磨牙颊侧骨板厚度,使用配对t检验进行统计学分析。结果:上颌第一前磨牙牙弓扩宽度为(3.76±2.15)mm,上颌第一磨牙处牙弓扩宽度为(3.43±2.52)mm。上颌第一磨牙牙冠倾斜度改变:左侧(1.42°±1.05°),右侧(1.59°±1.23°);上颌第一磨牙颊侧骨板厚度减少:左侧(0.71±0.67)mm,右侧(0.69±0.45)mm。结论 :上颌快速扩弓后,在CBCT上测量前磨牙区及磨牙区牙弓宽度明显增加,牙冠颊向倾斜度增大说明牙齿移动为倾斜移动而非整体平行移动。第一磨牙颊侧骨板厚度减少,应严密观察颊侧炎症情况以避免牙周破坏。

Objective： To evaluate the cone beam computer tomography（CBCT） changes of teeth and alveolar bone after using rapid maxillary expansion. Methods： 24 patients in the need for rapid maxillary expansion, before and after the treatment shooting CBCT as a chnical data, measuring the inclination of maxillary first premolar and maxillary first molar in CBCT on the central fossa width of maxillary first molar, maxillary first molar buccal bone thickness, using paired testing statistical differences. Results： The maxillary first premolar arch expansion width is （3.76±2.15） mm, the maxillary first molar dental arch expansion width is （3.43±2.52） ram. Maxillary first molar crown inclination change left （1.42°±1.05°）, （1.59°±1.23°） on the right side. Maxillary first molar buccal bone thickness was reduced： left（0.71±0.67） ram, right（0.69±0.45） ram. Conclusion： After rapid maxillary expansion, the measurement on CBCT show： the arch width of premolar and molar area increased obviously, crown buccal inclination explain that teeth movement for tilt movement rather tham parallel movement as a whole. The first molar buccal bone plate thickness was reduced, we should observe the inflammation level of buccal side closely to avoid periodontal destruction.