激光扫描并三维重建对重庆地区正常数字化模型的测量

Measurement of dental cast with normal occlusion in Chongqing by laser scanning and three-dimensional reconstruction

背景:研究采用三维测量仪和计算机辅助系统分别对中国人正常牙齿颊侧和舌侧表面形态进行了三维测量,证实了中国人牙齿各数据与国外数据相比,有明显差异。目的:旨在获得重庆地区正常数字化模型牙体形态的矫正学数据资料,结合Andrews、国人测量结果及Ormco舌侧托槽数据,比较不同人种,不同地区牙体在唇(颊)侧,舌侧的形态差异,为个性化矫正系统提供测量依据。方法:激光扫描并三维重建45副重庆地区未经矫正治疗的正常数字化模型,通过计算机辅助系统精密测量唇(颊)侧及舌侧各4项测量指标:牙冠轴倾角、转矩角,凸距和磨牙补偿角。结果与结论:重庆地区正常牙体的矫正学测量结果特点:①牙冠轴倾度角:上前牙,尖牙较白种人直立;双尖牙,磨牙近中倾斜明显。②牙冠转矩角:上前牙较唇倾,磨牙舌倾较白种人明显,但倾斜度均小于国人。③牙冠凸距:上下磨牙凸距比白种人大,同时,尖牙凸距比国人大。④磨牙补偿角:上颌磨牙补偿角较白种人偏小,与国人大致相似。结果表明,重庆地区正常的牙齿形态与白种人,国人有较大的差别,统计显示有其自身特征。测量方法可为直丝弓矫治技术,舌侧矫治技术提供准确的牙体矫正学所需数据,有助于制订个性化的矫正方案,帮助正畸医生更全面和客观地评估不同地区、不同人种的牙畸形特征。

BACKGROUND：Morphological measurement of the tooth buccal and lingual surface measured by three-dimensional measuring instrument and computer-aided system confirms that there are significant differences of the teeth date between Chinese and foreigner.OBJECTIVE：To obtain the morphological characters of normal occlusion in Chongqing with the purpose of providing evidence for individual treatment system,and to study the discrimination in tooth profile of different races and various areas,through comparing the data of this study with those of Andrews,other domestic researchers and Ormco lingual brackets.METHODS：Forty-five casts of non-orthodontic subjects（21 males and 24 females） with normal occlusion were examined using the ATOS three-dimensional lasing scanner system.Then,the data of digital three-dimensional dental casts,including crown angulation,inclination,facial prominence and offset angle of molars both of labial and lingual surfaces of the teeth was calculated and analyzed statistically by computer-aided system.RESULTS AND CONCLUSION：Chongqing people had their own ethnic characteristics in normal occlusion：①the crown angulation of the upper incisors and canines were more upright,while the premolars and molars were medially more inclined compared with Caucasian.②the upper incisors were inclined more to the labial side,while the upper molars to the lingual side,but the inclination were smaller than that of domestic researchers＇ study.③the facial prominence of molars was larger than that of Caucasian and the facial prominence of canines was larger than domestic researchers＇ study.④the offset angle of upper first molars was smaller,but was similar to that of domestic researchers＇ study.Tooth profile in Chongqing was significantly different from that of Caucasian and domestic residents and had their own characteristics.The result can not only provide evidence for straight wire technique and lingual therapy,but also help our clinicians to assess the craniofacial malformation completely and objectively for diagnosis and plan individual treatment for patients from different races and various areas.