常用颌骨矢状向位置关系评价指标的准确性和可靠性分析

Accuracy and Reliability Analysis of Commonly Used Cephalometric Norm of Anteroposterior Skeletal Occlu-sion

目的分析常用颌骨矢状向位置关系评价指标的准确性和可靠性。方法选择恒牙期208名患者的数码X线头颅定位侧位片和面部正侧位照片进行颌骨矢状向位置关系(骨性Ⅰ类、Ⅱ类和Ⅲ类)评判,并以此为标准对ANB角、APDI值、Wits值和A点凸度分别在骨性Ⅰ类、Ⅱ类和Ⅲ类错畸形中进行分析,并对以上4项测量指标进行相关分析。结果ANB角、APDI值、Wits值和A点凸度在骨性Ⅰ类、Ⅱ类和Ⅲ类错畸形中均具有显著性差异,APDI的变异系数较小,其余3项的变异系数波动较大。ANB角、APDI值、Wits值和A点凸度4项测量指标均具有高相关性。结论ANB角、APDI值、Wits值和A点凸度4项测量指标在评价骨性Ⅰ类、Ⅱ类和Ⅲ类错畸形时均具有一定的准确性,而APDI值的可靠性更好,并提示多项测量指标均指示为同一类错畸形时,结果的可靠性更高。

Objective To analyze the accuracy and reliabihty of commonly used cephalometric norm of anteroposterior skeletal occlusion. Methods 208 lateral cephalograms of patients with permanent occlusions were divided into skeletal Class Ⅰ, skeletal Class Ⅱ, and skeletal Class Ⅲ by lateral cephalograms and facial photos. Four items including ANB, APDI, Wits and A convexity were measured by independent sample t-test and coeiffient of variation in skeletal Class Ⅰ, skeletal Class Ⅱ, and skeletal Class Ⅲ respectively. Meanwhile, the coeificient of correlation between ANB, APDI, Wits and A convexity were determined. Results Significant differences were found in skeletal Class Ⅰ, skeletal Class Ⅱ, and skeletal Class Ⅲ using ANB, APDI, Wits and A convexity as cephalometric norm of anteroposterior skeletal occlusion respectively. The coefficient of variation of APDI was minor compared with other three measurements. All measurements had significant association with each other by Pearson correlation analysis. Conclusion It is accurate to use ANB, APDI, Wits and A convexity as cephalomettic norm of anteroposterior skeletal occlusion in skeletal Class Ⅰ, skele＇tal Class Ⅱ, and skeletal Class Ⅲ. However, the values of APDI are more reliable as cephalometric norm and will improve the reliability by measuring a tew cephalometric values of anteroposterior skeletal occlusion.