Hwang Soonshin, Choi Yoon Jeong, Jung Sooin, Kim Sujin, Chung Chooryung J, Kim Kyung-Ho
Department of Orthodontics, Gangnam Severance Dental Hospital, College of Dentistry, Yonsei University, Seoul, Korea.
Department of Orthodontics and Institute of Craniofacial Deformity, College of Dentistry, Yonsei University, Seoul, Korea.
Korean J Orthod. 2020 Mar;50(2):98-107. doi: 10.4041/kjod.2020.50.2.98. Epub 2020 Mar 24.
The aim of this study was to compare posterior tooth inclinations, occlusal force, and contact area of adults with different sagittal malocclusions.
Transverse skeletal parameters and posterior tooth inclinations were evaluated using cone beam computed tomography images, and occlusal force as well as contact area were assessed using pressure-sensitive films in 124 normodivergent adults. A linear mixed model was used to cluster posterior teeth into maxillary premolar, maxillary molar, mandibular premolar, and mandibular molar groups. Differences among Class I, II, and III groups were compared using an analysis of variance test and least significant difference test. Correlations of posterior dental inclinations to occlusal function were analyzed using Pearson's correlation analysis.
In male subjects, maxillary premolars and molars had the smallest inclinations in the Class II group while maxillary molars had the greatest inclinations in the Class III group. In female subjects, maxillary molars had the smallest inclinations in the Class II group, while maxillary premolars and molars had the greatest inclinations in the Class III group. Occlusal force and contact area were not significantly different among Class I, II, and III groups.
Premolar and molar inclinations showed compensatory inclinations to overcome anteroposterior skeletal discrepancy in the Class II and III groups; however, their occlusal force and contact area were similar to those of Class I group. In subjects with normodivergent facial patterns, although posterior tooth inclinations may vary, difference in occlusal function may be clinically insignificant in adults with Class I, II, and III malocclusions.
本研究旨在比较不同矢状向错牙合畸形成年人的后牙倾斜度、牙合力及接触面积。
使用锥形束计算机断层扫描图像评估横向骨骼参数和后牙倾斜度,采用压敏膜评估124例垂直生长型正常成年人的牙合力及接触面积。采用线性混合模型将后牙分为上颌前磨牙、上颌磨牙、下颌前磨牙和下颌磨牙组。使用方差分析和最小显著差检验比较安氏Ⅰ类、Ⅱ类和Ⅲ类组之间的差异。采用Pearson相关分析分析后牙倾斜度与牙合功能的相关性。
在男性受试者中,安氏Ⅱ类组上颌前磨牙和磨牙的倾斜度最小,而安氏Ⅲ类组上颌磨牙的倾斜度最大。在女性受试者中,安氏Ⅱ类组上颌磨牙的倾斜度最小,而安氏Ⅲ类组上颌前磨牙和磨牙的倾斜度最大。安氏Ⅰ类、Ⅱ类和Ⅲ类组之间的牙合力和接触面积无显著差异。
前磨牙和磨牙倾斜度在安氏Ⅱ类和Ⅲ类组中表现出代偿性倾斜以克服前后向骨骼差异;然而,它们的牙合力和接触面积与安氏Ⅰ类组相似。在垂直生长型面部模式的受试者中,尽管后牙倾斜度可能不同,但对于安氏Ⅰ类、Ⅱ类和Ⅲ类错牙合畸形的成年人,牙合功能差异在临床上可能并不显著。