上海地区上前牙先天缺失患者牙颌面形态分析

Congenital Absence of Upper Anterior Teeth-A Dentofacial Morphologic Analysis

目的 了解上海地区上前牙先天缺失儿童的牙颌面形态特征 ,探讨上前牙先天缺失对颌面部生长发育的影响。方法 对 37例上前牙先天缺失儿童进行X线头影测量分析 ,并与正常值比较。结果 上前牙先天缺失儿童头影测量无性别差异。与正常值比较 ,上前牙先天缺失儿童颌凸角、ANB、AoBo减小 ,上下牙槽座角增大 ,Y轴角、下颌平面角减小 ,牙合平面角减小 ,上中切牙倾角增大 ,下中切牙倾角减小 ,软组织面凸角减小 ,上唇倾角增大 ,鼻唇角减小。结论 上前牙先天缺失可引起上颌发育不足 ,对下颌大小无影响 ,但可引起下颌平面逆时针旋转。

Objective This study was designed to examine the dentofacial morphology of the children in Shanghai with congenital absence of upper anterior teeth.Methods Cephalometric analysis for 37 children with congenital absence of upper anterior teeth was conducted and was compared with that of the normal ones.Results (1)There was no significant difference in all measurements between gender.(2)Craniofacial defection included a small SNA, a small ANB,a small AoBo,a small angle of convexity ,and a large AB plane angle. Vertical facial dimensions which was shown by Y axis and mandibular plane angle significantly decreased. Examination for soft tissue also revealed a small convexity of soft tissue and a large CmSnUL.(3)A compensative proclination of the upper central incisors as well as the upper lip was also found.Conclusion Patients with congenital absence of upper anterior teeth might have a small maxilla,a relatively normal mandibular dimension,an anticlock rotation of the mandible plane, and a compensative proclination of the upper central incisors and the upper lip.