运用逐步回归分析预测未萌第三磨牙冠宽

Prediction of the Third Molar Coronal Size of Canines by Stepwise Regression Analysis

目的 建立第三磨牙与其他牙冠宽的方程,以预测未萌第三磨牙冠宽。方法 用游标卡尺测量成年人牙列模型,通过逐步回归分析建立第三磨牙与其他牙冠宽的回归方程。结果 第三磨牙与其他牙冠宽的相关方程为:L8=1.23+0.70L3+0.45L5+0.4L6-0.3L7;U8=-2.70-0.22Us+0.75U6+0.56U7。结论 利用此方程可以较准确预测未萌第三磨牙的冠宽,这对于治疗方案的制定具有参考价值。

Objective To establish the equations between the third molar and the other teeth in order to predict the third molar coronal size. Method Stepwise regression analysis was made to establish a method for the prediction of the third molar coronal size. The samples were adult dental casts that had all teeth from the central incisor to the third molar. Mesiodis-tal tooth crown sizes were measured with sliding calipers. Results Two equations are gotten:L8 = 1.23 + 0.70L3 + 0. 45L5 + 0. 4L6 -0. 3L7 and U8 =-2. 70-0. 22U5 + 0. 75U6 + 0. 56U7. The mean of the absolute values of the difference between the actual values and the predicted values was less than 0. 5mm. Conclusion These eaquations give us an easy way to get the third molar coronal size.