牙列拥挤的解除与上前牙唇倾度及突度变化的相关性研究

目的：探讨解除牙列拥挤对上前牙唇倾度及突度的影响。方法：选择50例牙列拥挤的非拔牙正畸患者，通过术前术后模型及头影测量分析，通过直线相关与回归分析，比较牙列拥挤的解除量对上前牙唇倾度及突度的影响。结果：每毫米拥挤度的解除会增加上前牙唇倾度（U1－SN）0．8°及突度（U1－AP）0．4 mm，但是直线回归方程的拟合优度检验数值较低，需要进行包含更多参数的多元线性回归方程进一步分析。结论：每毫米拥挤度的解除会增加上前牙唇倾度0．8°及突度0．4 mm。结果表明唇倾度及突度的改善是由多方面因素决定的，不单纯与拥挤度的解除量相关。

The evaluation of the relationship between the alleviation of crowding and the changes in maxillary incisor pro-clination and protrusion

Objective:To examine changes in maxillary incisor proclination and protrusion resulting from alleviation of crowding.Methods:Records of 50 patients with crowded dentition treated without extractions or interproximal enamel re-duction in the maxillary arch were included.Pre-and post-treatment cephalograms and models were examined to determine changes in incisor proclination,protrusion and crowding.Results:For every millimeter of crowding alleviation,increases in in-cisor proclination(U1-SN)and protrusion(U1-AP) of 0.8°and 0.4 mm,respectively,we found,high variability was calculat-ed for both linear variables that can be reduced by incorporating other variables by multilinear regression.Conclusion:For every millimeter of crowding alleviated,0.8°of proclination and 0.4 mm of protrusion are expected.Our results indicate that proclination is mulifactorial and cannot be explained solely by the amount of crowding alleviated during orthodontic treatment.