切牙先天缺失患者颅颌面形态分析

目的 了解福建地区切牙先天缺失患者的颅颌面形态特征,探讨切牙先天缺失对颌面部生长发育的影响.方法 将78例切牙先天缺失患者分为3组:L1组,先天缺失1颗下切牙;L2组,先天缺失2颗下切牙;U2组,先天缺失2颗上颌侧切牙;12例个别正常牙合作为对照组.对受试者头颅侧位片进行头影测量分析.结果 与对照组比较,L1组ANB增大(P＜0.05),其余指标无明显差异;L2组ANB、SNA、UL-EL增大,N-S-Ar减小(P＜0.05);U2组H角、L1-NB、MP-SN、N-ANS、NA-PA、N-Me、N-S-Ar减小,SNB增大,U1-L1增大(P＜0.05).结论 下颌切牙先天缺失患者上颌骨相对前突,上颌侧切牙先天缺失患者下颌前突,呈Ⅲ类骨型趋向.上、下切牙缺失对颅颌面结构具有不同的影响.

The Effects of Congenital Missing Incisor on Dentofacial Structures

Objective To investigate the effects of congenital missing incisor on dentofacial structures. Methods 78 subjects with congenital missing incisor were divided into 3 groups: L1 group, unilateral lower incisor missing, L2 group, bilateral lower incisor missing, U2 group, bilateral upper incisor missing. Cephalometric analysis was conducted and compared with control group of normal occlusion. Results ANB angle was significantly larger in L1 group and L2 group (P<0.05) than the control group, SNA angle was significantly bigger in L2 group. H angle, L1-NB, MP-SN, N-ANS, NA-PA, N-Me, N-S-Ar were significantly larger and SNB angle and U1-L1 angle were smaller (P<0.05). Conclusion Upper Congenial minssing incisor would result in the protrusion of the mandible, and counterclockwise rotation of the mandible, lower Ongonitial missing incisor agenesis would lead to the protrusion of the maxilla.