作者根据Johnston对骨和牙弓的分析法评价青少年和成人之间Ⅱ类错(牙合)矫治效果的差异。结果:成人(牙合)平面的倾斜度明显变大;下颌磨牙的近中移动量,在除去生长量以外。成人和青少年没有差异;成人下颌骨无明显生长,但表现为向下后旋转;对Ⅱ类磨牙关系的矫治,青少年的上下颌骨差异性生长占矫治效果的70％, Based on Johnston's analysis of bone and dental arch, the authors evaluated the differences in the effects of class II malocclusion between adolescents and adults. Results: The inclination of the adult occlusal plane was obviously larger than that of the mandibular molars. There was no difference between adults and adolescents. There was no obvious growth in adult mandible, but showed downward rotation. The treatment of type II molars showed that the differential growth of upper and lower jaws in adolescents accounted for 70%