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

doi:10.19439/j.sjos.2017.01.014

Abstract

Abstract: 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.

Key words: Third molar, Gonial angle, Upper Gonial angle, Lower Gonial angle

CLC Number:

R783

CHEN Yan-na, ZHENG Bo-wen, LIU Yi. Study of the relationship between congenital missing of the third molar and the development of the mandibular angle[J]. Shanghai Journal of Stomatology, 2017, 26(1): 69-72.

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