东北地区227例患者第三磨牙先天缺失与下颌角发育之间的关系

Study of the relationship between congenital missing of the third molar and the development of the mandibular angle

目的 :通过对第三磨牙先天缺失情况及缺失数目的研究,分析第三磨牙先天缺失与下颌角发育之间的关系。方法:选取227例患者的曲面体层片及头颅侧位片作为实验组,其中每例至少有1颗第三磨牙先天缺失;同时选取227例4颗第三磨牙均存在的患者作为对照组。采用Winceph8.0软件对所有研究对象的头颅侧位片进行测量,采用SPSS17.0软件包对数据进行独立样本t检验、单样本t检验、方差分析、线性回归分析。结果 :对照组的Gonial角、上部Gonial角、下部Gonial角均大于实验组,且有显著差异,但性别间无显著差异。Gonial角、上部Gonial角、下部Gonial角与第三磨牙先天缺失数目之间无显著差异。结论:第三磨牙先天缺失与Gonial角、上部Gonial角、下部Gonial角有密切联系,但与性别无显著关系,患者具有短面的颅面结构。第三磨牙先天缺失个数与Gonial角等无显著联系。

PURPOSE： Based on the research of the congenital missing of the third molar and the missing number, the relationship beteen congenital missing of the third molar and the development of the mandibular angle was evaluated. METHODS： Patients were divided into experimental group and control group, the experimental group included 227 patients, each had at least one of the third molars congenital lost; 227 patients who had four third molar were selected as control group. Winceph software was used to measure the lateral cephalograms. SPSS17.0 software package was used to perform statistical analysis. RESULTS： Gonial angle, upper Gonial angle and lower Gonial angle between the experimental group and the control group showed significant difference and the values in the experimental group were significantly smaller than in the control group, but there was no gender difference between the two groups.There was no difference between Gonial angle, upper Gonial angle,lower Gonial angle and the missing number of the third molar. CONCLUSIONS： There is a close relationship between congenital missing third molar and Gonial angle, upper Gonial angle, lower Gonial angle, but there is no significant association with gender and the patients with congenital missing third molar have shorter craniofacial structure. Congenital missing number of the third molar has no significant association with Gonial angle, upper Gonial angle and lower Gonial angle.