多元回归方法建立山东地区恒牙初期青少年个体化头影测量颅颌关系浮动正常值的研究

Study on floating norms of individual cephalometric craniofacial patterns of teenagers in early permanent dentition in Shandong by means of multiple regression

目的采用多元回归方法建立山东地区恒牙初期青少年个体化头影测量颅颌关系浮动正常值,并探讨其临床应用方法。方法搜集山东地区未接受正畸治疗的恒牙初期正常青少年120例,其中男69例,女51例,12～16岁。选择在判断矢状方向和垂直方向颅颌关系中最常用的5项X线头影测量指标(SNA,SN-PP,NSBa,SN-MP,SNB),并对各测量指标进行多元回归统计分析,建立其个体化头影测量颅颌关系浮动正常值。结果①5项测量指标之间均存在显著的相关性;②以SNB为自变量,分别建立与其余4项测量指标的直线回归方程;③分别以任意4项测量指标为自变量,剩余的1项测量指标为因变量进行多元回归统计分析,计算得出5项测量指标各自的预计标准误(SE),其中SNA为1.95,SN-PP 2.79,NSBa4.57,SN-MP 4.35,SNB 1.87;④在此基础上,最终建立起山东地区恒牙初期青少年的个体化头影测量颅颌关系浮动正常值。结论本研究为恒牙初期青少年正畸患者提供了一套个体化的头影测量诊断方法,特别适用于临床中进行正畸治疗的青少年患者。

Objective The purpose of this study was to provide cephalometric floating norms as a way to evaluate individual cranio facial patterns of teenagers in early permanent dentition in Shandong by means of multiple regression, and to explore its clinical applica- tions. Methods 120 teenagers in early permanent dentition with normal occlusion were selected in Shandong area, including 69 males and 59 females （aged from 12 to 16 years old）. Five X-ray cephalometric indexes consisting of SNA, SN-PP, NSBa, SN-MP, and SNB were selected and analyzed by multiple regression as they were commonly used to determine the sagittal and vertical correlations of oc- clusion. Establish floating norms of individual cephalometric craniofacial pattens. Results （~ There were significant correlations among the five indexes. ① Bivariate linear regression equations were established based on the other four indexes with SNB as the independent variable. ②Standard errors of the estimate （SE） of each index were calculated by multiple regression analysis in which any four inde xes performed as the independent variables and the rest one as the dependent variable （ SNA = 1.95 , SN-PP = 2.79 , NSBa = 4.57 , SN-MP = 4.35 ,SNB = 1.87 ）. ③Finally, cephalometric floating norms to evaluate the craniofacial patterns of teenagers in Shandong was established. Conclusions The study provides an individualized cephalometric measurement and diagnosis method,which is parti- cular suitable for teenager patients in clinical orthodontic treatment.