西安地区恒牙早期Ⅲ类错颅面类型构成分析

Component Analysis of Craniofacial Type of Xi'an Chinese with Class Ⅲ Malocclusion in the Early Permanent Dentition

目的:分析西安地区恒牙早期Ⅲ类错颅面类型的构成。方法:以本院正畸科2003～2008年恒牙早期Ⅲ类错患者为研究对象,采用计算机辅助X线头影测量技术,分析恒牙早期Ⅲ类患者在矢状向与垂直向的构成。结果:恒牙早期Ⅲ类错矢状向主要表现形式为双颌发育基本正常或上颌正常,下颌发育过度。垂直向主要表现为均角型。低角型、高角型差异不显著。交叉分析显示:上下颌均发育正常的均角型患者和上颌正常,下颌发育过度的均角型患者最多见;其次是上颌发育不足,下颌正常的均角型患者。结论:恒牙早期Ⅲ类错在矢状向与垂直向均表现出一定的趋势,分析与研究这类错的构成加深了对西安地区Ⅲ类错患者颅面类型的认识,并对临床上合理矫治提供一定的参考。

Objective：To analyze craniofacial type composition of Class Ⅲ malocclusion in early permanent dentition in the Xi＇an region. Methods：We performed a retrospective study on craniofacial type of the Class Ⅲ malocclusion patients admitted to the Department of Orthodontics,Stomatology Hospital,the Fourth Military Medical University,during 2003-2008. The computer-aided cephalometric X technology had been used and the features of class III malocclusion patients in early permanent dentition were studied. Results：In early permanent dentition,craniofacial types in sagittal directions were mainly manifested as maxillary and mandibular normal or maxillary normal with mandibular hyperplasia. Craniofacial types in vertical direction were mainly manifested as average angle,and seldom as low-angle and high-angle. The cross-analysis of sagittal and vertical craniofacial morphology was performed. Both maxillary and mandibular normal and maxillary normal with mandibular hyperplasia in average angle patients were predominant,and followed by maxillary hypoplasia with mandibular normal combined with average angle. Conclusion：It was demonstrated that class III malocclusion patient in early permanent dentition has either sagittal or vertical features. The component analysis can play a very important role in understanding the detailed features of class III malocclusion. And more important,it is helpful for the future study on the early treatment of class III malocclusion.