摘要
目的通过锥形束CT(CBCT)影像进行交互式医学影像控制系统(Mimics)的三维重建,为临床矫治中切牙唇倾角度控制及正颌手术中骨块移动量设计提供理论参考。方法对30例采用正畸-正颌联合治疗的成人骨性Ⅲ类患者正畸去代偿前后分别拍摄CBCT,使用Mimics 10.01软件对前牙进行三维重建并以釉牙骨质界分离牙冠和牙根,分别测量正畸去代偿前后的上下切牙唇倾角度及牙根体积。通过统计学方法得出正畸去代偿前后牙根体积变化量与唇倾角度变化量之间的量化关系。结果上下切牙牙根体积在去代偿后发生了明显减小,差异有统计学意义;不同性别及不同牙位牙根体积的变化差异无统计学意义;当切牙唇倾角度变化量达到7°及以上时,牙根体积的改变量与唇倾角度改变量之间存在线性关系并满足=-21.416+5.618X。结论成人骨性Ⅲ类错正畸去代偿后当前牙唇倾角度发生7°及以上的变化时切牙牙根发生明显吸收。
Objective To evaluate incisor root resorption of adults with skeletal classⅢmalocclusion through three-dimensional reconstruction of cone beam computed tomography （CBCT） image using interacting medical imaging control sys？tem （Mimics） and then offer guidance for labially tilted angle control in orthodontic treatment and distance of bone moving in surgery. Methods Adults of skeletal class Ⅲ malocclusion （n=30） who underwent orthodontic-orthognathic combination treatment were included in this study. CBCT images were then reconstructed three-dimensionally using Mimics 10.01. Each incisor were separated at cementum-enamel junction as crown and root. Labially tilted angle and root volumes of each inci？sor were measured before and after operations. At last, the correlativity between root resorption and labially tilted angle was calculated through statistic analysis. Results The decrement of upper, lower and front incisors’root volumes upon treat？ment is statistically significant. However, there is no statistically significant difference of incisor ’s root volumes among eight incisors nor between different gender. There is linear correlation between root volumes and labially tilted angle when the lat？ter changes 7° or more when they followed the fomular =-21.416＋5.618X. Conclusion For adults with skeletal classⅢmalocclusion, orthodontic treatment before orthognathic surgery decrease incisor root volumes when labially tilted angle changes 7° or more.
出处
《天津医药》
CAS
2015年第4期390-393,共4页
Tianjin Medical Journal
