GoGn-SN角和MP-FH角差异性研究

Study on the Differences between GoGn-SN Angle and MP-FH Angle

目的：探讨头颅定位例位片中GoGn-SN角与MP-FH角测量值的差异性及其影响因素,以期为临床诊断提供参考。方法：随机选取120例正常个体（年龄1 8-25岁,男女各60例）、200例未经正畸治疗的错患者（年龄1 8-30岁,男女各100例）为研究样本,对其头颅定位侧位片进行测量,分析正常个体GoGn-SN角与MP-FH角差值分布范围以及影响正常个体和错患者GoGn-SN角与MP-FH角差值大小的因素。结果：正常个体GoGn-SN角大于MP-FH角（P〈0.05）,其差值为（5.1 0±2.93）°且没有明显的性别差异性（P〉0.05）,差值的大小与SN-FH角显著相关（P〈0.01）。错患者GoGn-SN角与MP-FH角差异与SN-FH角正相关（P〈0.01）、与Y轴角负相关（P〈0.01）,与ANB角无明显相关性（P〉0.05）。结论：正常个体GoGn-SN角的测量值一般高于MP-FH角5°左右;下颌下后旋转生长型的错牙撼者GoGn-SN角与MP-FH角测量值的差值有减小趋势,下颌前上旋转生长型的错患者则有增大趋势。

Objective To explore the differences between GoGn-SN angle and MP-FH angle and the influencing factors in order to provide theoretical basis for clinical diagnosis. Methods The lateral cephalograms of 120 adults（18-25 years old,60 males and 60 females） with normal occlusion and 200 malocclusion patients（18-30 years old,100 males and 100 females） before treatment were collected randomly. They were used to investigate the range of differences between GoGn-SN angle and MP- FH angle among adults with normal occlusion, and to analyze the influencing factors both in individuals with normal occlusion and malocclusion. Results For adults with normal occlusion, GoGn-SN angle was bigger than MP-FH angle（P〈0.05）,and no significant gender difference was shown for the difference between GoGn-SN angle and MP-FH angle（P〉0.05）,which was （5.10＋2.93）- and showed significant correlation with SN-FH angle（P〈0.01）. SN-FH angle was correlative with the difference between GoGn-SN angle and MP-FH angle significantly（P〈0.01） among malocclusion patients, and negative significant correlation was shown between the difference and Y axis angle （P〈0.01）,while no significant correlation with ANB angle（P〉0.05）. Conclusion GoGn-SN angle is about 5-bigger than MP-FH angle in adults with normal occlusion, and the difference between GoGn-SN angle and MP-FH angle is smaller in malocclusion patients with mandibular backward rotation, while it is bigger in patients with mandibular forward rotation.