数字影像系统测量分析融合牙乳牙列

目的探讨Digora数字影像系统测量牙列模型的新方法并用此方法分析乳牙融合牙列的特征。方法选取AB融合牙模型和BC融合牙模型各14副。用电子游标卡尺和Digora数字影像系统分别测量牙列,并统计分析结果。结果游标卡尺测量值稍大于Digora系统测量值,且两方法所测各值均相关(r>0.80,P<0.01),比值较稳定(均值为1.05)。融合牙的牙冠宽度明显小于非融合侧两同名牙冠宽度的和(P<0.05)。AB融合牙组CC—CC和CL—CL大于BC融合组(P<0.05)。融合牙组下颌对称性系数显示牙列的非对称状,中线偏向融合侧。且下颌融合侧三角形面积小于非融合侧三角形面积(P<0.01)。结论Digora数字影像系统测量结果稳定,有利于资料保存,便于临床使用;融合牙牙列与正常牙列的差异应予以重视。

Analysis of fused tooth in primary dentition by digital image system

Objective To study a new method of dental cast measurement using Digora digital image system, and investigate the characteristics of the fused tooth in primary dentition so as to support the basic studies and offer the references to preventive dentition correction. Methods 14 models with the fused primary tooth of AB and 14 models with the fused primary tooth of BC were chosen. They were measured by both vernier caliper and Digora digital image system, and the results were analyzed statistically. Results The mean values from vernier caliper were bigger than those from Digora software and the results of two groups had high correlation(r>0.80, P<0.01). The width of fused tooth crown was significantly smaller than the sum width of homonymy tooth crown in the opposite side of the same dentition(P<0.05). CC—CC, CL—CL of AB is bigger than that of BC (P<0.05).The measured values of upper dental arch were not different between two groups(P>0.05).Symmetry coefficient of the fused tooth dentition showed the midline leans to fused side, and the area of triangle in fused side is smaller than that in unfused side. Conclusion Digora digital image system is a steady, feasible and convenient new method to measure dental cast. The dentist should pay attention to the difference between fused tooth dentition and normal dentition which has effects on the primary dentition.