The purpose of this study was to investigate the difference of craniofacial complex, teeth and soft tissue between skeletal ClassⅠ malocclusion and skeletal ClassⅡ malocclusion and to classify the facial types of ClassⅡ malocclusion in the stage of SMI 4 and 5 in Korean adolescence. The study was performed to the patients in the stage of SMI 4 and 5 who came to the orthodontic department of a dental clinic, Gangam Severance hospital of Yonsei University between 2006 and 2016. They were 41 males and 43 females with skeletal ClassⅠ malocclusion and 39 males and 37 females with skeletal ClassⅡ malocclusion. The lateral cephalograms had been analysed to calculate average values of significance test for ClassⅠ and ClassⅡ about skeletal measurement (38 items), measurements of soft tissue (23 items) and dental measurement(10 items), and categorized horizontal facial types of maxilla and mandibule. The results obtained were as follows. 1. The anteroposterior position of the maxilla had no difference between skeletal ClassⅠ malocclusion and skeletal ClassⅡ malocclusion regardless of sex. (p > 0.05) 2. The mandibule of skeletal ClassⅡ malocclusion was located more posteriorly and the size was smaller than that of skeletal ClassⅠ maloccusion. (p 0.05), but the chin area of skeletal ClassⅡ malocclusion was more posteriorly positioned(p < 0.05). 5. There was no difference between two groups about the upper and lower anterior teeth and molars’ anteroposterior and vertical position except the vertical distance of the upper anterior teeth of female. 6. According to the facial type of skeletal ClassⅡ malocclusion classification, the highest rate (30.26% each) had been shown in the cases with the Maxillas in normal range and the Mandibules in retrognathic range, and in the cases with the Maxillas and the Mandibules in normal range. 23,68% had been shown in the cases with the Maxillas anteriorly located and the Mandibules in normal range.open석
