【摘要】 目的探讨下切牙先天缺失对颅颌面结构的影响。方法选取下切牙先天缺失的正畸患者29例纳入下切牙缺失组,选取安氏I类轻度拥挤患者20例为对照组,拍摄头颅侧位片,进行头影测量分析的对比研究。结果与对照组比较,下切牙缺失组SNB角、ANB角减小;代表上下前牙位置关系的U1-NA、U1/NA、L1-NB、L1/NB、L1/MP均减小,U1/L1夹角增大;FH/MP增大;后颅底长Ar-S增大;全面高Gn-N、下面高ANS-M e增大;颏部突度Po-NB增大,差异有统计学意义(P<0.05)。结论下切牙先天缺失患者上颌骨发育基本正常,下颌骨略后缩,上下切牙舌倾,颏部发育较好。更多还原

【Abstract】 Objective The study was to investigate the dento-facial morphology of children with congenital absence of mandibular incisor.Methods The sample consisted 29 patients with one lower incisor missing and 20 patients with class one mild crowding.The pre-treatment cephalometric films of all of them were measured to assess the dento-facial morphology.Twenty-four parameters were evaluated.Results Compared with the control group,the incisor missing group has decreased SNB and ANB angle;U1-NA,U1/NA,L1-NB,L1/NB,L1/MP decreased;U1/L1 angle increased;FH/MP angle increased;Ar-S increased;Gn-N,ANS-Me increased;Po-NB increased;P<0.05.Conclusion Patients with lower incisor missing might have a normal maxilla,a retrude mandible,a more clockwise-rotated mandible plane,upper and lower incisor retrocline and a protrude pogion.更多还原