快速整体内收上颌前牙对犬牙根吸收影响的扫描电镜观察

目的研究牙槽外科辅助快速整体内收上颌前牙对实验犬前牙牙根的影响。方法建立牙槽外科辅助快速整体内收上颌前牙的比格犬动物模型后,连续加力12 d,速度0.5 mm/d,分别于加力停止并固定1 d,14 d,28 d后随机处死3只实验犬,拔出一侧上颌第三切牙,制备标本行扫描电镜观察。结果加力停止1 d及14 d后牙根吸收明显,停止加力28 d后,牙根吸收面积明显减小:牙根颈部28 d与1 d(t=25.075,P=0.014)、28 d与14 d(t=17.444,P=0.056)比较,差异有统计学意义;牙根尖部28 d与1 d(t=26.436,P=0.000)、28 d与14 d(t=18.229,P=0.003)比较,差异有统计学意义。结论牙槽外科辅助快速整体内收上颌前牙会造成一定程度的牙根吸收,随着加力停止后固定时间的延长,牙根吸收可明显修复。

Root resorption after rapid maxillary anterior teeth retraction en masse as detected by scanning electron microscopy

ObjectiveTo investigate the presence and severity of root resorption after rapid maxillary anterior teeth retraction en masse by scanning electron microscopy.MethodsAfter building up the animal experimental model of rapid maxillary anterior teeth retraction en mass in beagle dogs,the distraction device was activated with the speed of0.5 mm/d for 12 days.Three animals were executed randomly after distraction and after fixed for 1 d,14 d and 28 d respectively.One maxillary third incisor of each dog was extracted to prepare for being detected by scanning electron microscopy.ResultsThe presence and severity of root resorption were evident after fixed for 1 d and 14 d.After fixed for 28 d,the root resorption area showed better and there was significantly statistical difference.ConclusionThe results suggested that rapid maxillary anterior teeth retraction en masse aided by alveolar surgery could cause anterior teeth root resorption to some extent,but this could be repaired after consolidation for a period of time.