Effects of skeletal pattern on the expression of occlusal features
Zheng Xu, Lin Jiuxiang, Xie Yiyue Department of Orthodontics, Peking University School of Stomatology, Beijing 100081
Objective This research is to find out the skeletal factors which have influence on the occlusal features and to provide scientific basis for chinical diagnosis, treatment planning and understanding the malocclusion mechanism. Method 440 patients aged from 12-15 years were divided into three groups according to the molar relationship on the plaster model, including 160 children in both class Ⅰ and class Ⅱ groups and 120 children in class Ⅲ group. The control group consisted of 60 normal children in the same age range.Boys and girls are equal in number in all groups. The stepwise multiple regression was performed. Results Skeletal pattern had strongest influence on class Ⅲ occlusal features. The overbite and overjet in class Ⅱ group had the weakest influence on skeletal pattern; The main skeletal factors influencing malocclusion include the saggital and vertical skeletal relationship and the gradient of chin; The NA PoA angel is the most influential factor causing the variation of overjet, while the lower facial height was the most important skeletal factor affecting the variation of overbite. Conclusion Skeletal patten has limited influence on the occlusal pattern, and the extent of it′s influence on the three classes of Angle′s malocclusion is different. Clinically, skeletal pattern and occlusal partern must be considered respectively.