关键词: 错牙合 , 头影测量, 安氏分类

Abstract: Objective To study the effects of anatomical porion and mechanical porion on cephalometric measurements and influencing factors in the location relationships of different porions. Methods Totally 105 lateral cephalograms of post-juvenile patients were chosen，three items including FH-MP，FH-PP and FH-NP were measured according to different porions，and then the measurements were statistically analysed. Meanwhile，the effects of different malocclusions and genders on the location relationships of different porions were detected. Results Significant differences were found in measurements of FH-MP，FH-PP and FH-NP，but no differences were showed in perpendicular or horizontal distances between the anatomical porion and mechanical porion in different malocclusions，and the same result was found in different genders. Conclusion Significant differences exist in the locations between anatomical porion and mechanical porion，so one shouldn’t be confused with the other in cephalometric measurements.

Key words: malocclusion, cephalometry, Angle’s classification