Yi Huang1,2,3, Yinqiu Yan1,2, Jing Cao1,2, Bingjie Xie1,2, Xueling Xiao1,2, Mengqi Luo1,2, Ding Bai1,2, Xianglong Han4,5. 1. State Key Laboratory of Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, China. 2. Department of Orthodontics, West China School of Stomatology, Sichuan University, 14# 3rd Section, Ren-Min-Nan Road, Chengdu, 610041, China. 3. Department of Stomatology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China. 4. State Key Laboratory of Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, China. xhan@scu.edu.cn. 5. Department of Orthodontics, West China School of Stomatology, Sichuan University, 14# 3rd Section, Ren-Min-Nan Road, Chengdu, 610041, China. xhan@scu.edu.cn.
Abstract
OBJECTIVE: This study was designed to examine the relationship between third molar agenesis and skeletal morphology in the Chinese population. MATERIALS AND METHODS: A total of 1043 patients' records were analyzed with panoramic radiographs and cephalograms. Congenitally missing third molars were assessed with respect to gender, jaw, and side, and assessed in various types of facial morphology. Linear, angular, and proportional cephalometric measurements were analyzed and compared among the samples. For the evaluation of results, the following statistics were used: the Pearson χ 2 test, one-way ANOVA, and the Student-Newman-Keuls method. RESULTS: The overall prevalence of third molar agenesis was 28.7%. Missing third molars were more common in the maxilla and on the right side, while the difference was not statistically significant (P > 0.05) between genders. Every hypodontia group had a smaller SN-GoGn angle, Y-axis-FH angle, and a larger S-Go/N-Me ratio. The group with third molar agenesis in both jaws had smaller SNA and Wits values. The frequency of third molar agenesis in subjects with a Class II malocclusion was significantly lower than in other types of malocclusion (P < 0.05), and the incidence of third molar agenesis in hypodivergent growth pattern was higher than in other patterns (P < 0.05). CONCLUSION: The results demonstrate a possible association between third molar agenesis and both sagittal and vertical craniofacial morphology.
OBJECTIVE: This study was designed to examine the relationship between third molar agenesis and skeletal morphology in the Chinese population. MATERIALS AND METHODS: A total of 1043 patients' records were analyzed with panoramic radiographs and cephalograms. Congenitally missing third molars were assessed with respect to gender, jaw, and side, and assessed in various types of facial morphology. Linear, angular, and proportional cephalometric measurements were analyzed and compared among the samples. For the evaluation of results, the following statistics were used: the Pearson χ 2 test, one-way ANOVA, and the Student-Newman-Keuls method. RESULTS: The overall prevalence of third molar agenesis was 28.7%. Missing third molars were more common in the maxilla and on the right side, while the difference was not statistically significant (P > 0.05) between genders. Every hypodontia group had a smaller SN-GoGn angle, Y-axis-FH angle, and a larger S-Go/N-Me ratio. The group with third molar agenesis in both jaws had smaller SNA and Wits values. The frequency of third molar agenesis in subjects with a Class II malocclusion was significantly lower than in other types of malocclusion (P < 0.05), and the incidence of third molar agenesis in hypodivergent growth pattern was higher than in other patterns (P < 0.05). CONCLUSION: The results demonstrate a possible association between third molar agenesis and both sagittal and vertical craniofacial morphology.
Entities:
Keywords:
Congenital absence; Craniofacial morphology; Hypodontia; Third molar agenesis
Authors: Michael Nemec; Linda Schwarz; Michael H Bertl; Kristina Bertl; André Gahleitner; Philipp Mitteroecker; Erwin Jonke Journal: Clin Oral Investig Date: 2022-08-29 Impact factor: 3.606