基于Wilks’lambda的拔牙矫治逐步判别分析

Tooth extraction correction： Wilks＇ lambda discriminant analysis

目的验证利用wilks＇ lambda分析方法筛选对拔牙矫治判别影响最大的测量项目方法。方法选取100例正畸患者，年龄14～40岁，平均年龄23．6岁，男29例，女76例，对其进行常规头影测量分析。统计分析使用SPSS18．0软件包。应用wilks＇ lambda判别统计方法筛选对拔牙矫治影响最大项目。结果UIE—AB和NA／PA的计算结果差异有统计学意义（P〈0．05），并建立了一个拔牙矫治的回归方程为y=0．125×NA／PA＋0．351×UIE-AB-3．429，两者结合初始验证准确率为82．6%，交叉验证准确率为81．03％。结论上切牙至AB连线距离，NA／PA角度是良好的拔牙判定指标。

Objective To use Wilks＂ lambda discriminant analysis for screening of the greatest influence factors in tooth extraction correction and to establish a method for validation. Methods A total of 100 orthodontic patients were selected, aged 14 to 40 years, with average age of 23.6 years, 29 males and 76 females. The conventional cephalometry analysis was conducted. Statistical analysis was carried out with using SPSS 18.0 software package. Wilks＇ lambda statistical method was applied to filter the largest effect on tooth extraction treatment project. Results The UIE-AB and NA/PA calculation results showed statistical differences （P〈0.05）, and it set up a tooth extraction rectification regression equation for y = 0.125 × NA/PA＋0.351 X UIE-AP-3.429 ; a combination of the initial validation accuracy was 82.6%, and cross validation accuracy was 81.03%. Conclusions Incisor to AB line distance and angle of NA/PA are good tooth extraction judgement indexes.