正畸加载对自体移植牙预后影响的显微CT研究

Micro CT study of orthodontic loading on the prognosis of auto-transplanted teeth

目的建立不同时程正畸加载自体移植牙的动物模型,利用显微CT(Micro CT)研究正畸加载对其预后的影响。方法选取4只犬的16颗中切牙作为实验牙齿,在自体牙移植术后第1、4、8、12周分别进行正畸加载。加载1月后对实验牙齿及周围骨块拍摄Micro CT,进行形态学观察、数字化软件分析及三维重建。结果自体牙移植术后第4周、第8周进行正畸加载的移植牙,形态学观察无明显骨粘连、牙根吸收、牙周膜间隙增宽及根尖区牙槽骨密度减低;骨计量参数比较提示根尖区骨小梁破坏最少、骨小梁离散度低。结论通过Micro CT观测,可推断在犬自体牙移植术后第4周、第8周进行正畸加载,牙周愈合情况较好并可预防骨粘连的发生。

Objective To study the influence of orthodontic movement on the prognosis of autotransplanted teeth with Micro CT by establishing an animal model of autotransplantation teeth in dogs.Methods In 4 dogs,16 central incisors were chosen as experimental teeth.Orthodontic loading was conducted in the 1st,4th,8th and 12th week after autogenous teeth transplantation.At the end of first month,teeth and pieces of bones,including periodontal tissues,were scanned by Micro CT.The relevant parameters were analyzed by morphological observation,digital software analysis and three-dimensional reconstruction.Results The transplanted teeth loaded at the fourth and the eighth week showed no significant ankylosis and root resorption morphologically,were without obvious periodontal ligament space broadening and apical alveolar bone density diminution.Bone architecture quantization comparison presented the least apical trabecular bone damage and the lowest trabecular bone dispersion.Conclusion From experimental data obtained with Micro CT,it can the concluded that loading the autotransplanted teeth at the fourth to eighth week after transplantation can prevent ankylosis without an increase of root resorption.