A Comparative Study On The Chin Soft And Hard Tissue Morphology Of Different Vertical Skeletal Types In Han And Uyghur Adult Female And ClassⅡ~1

Objective:X-ray lateral cephalic radiographs were used to measure the various indexes of the chin soft and hard tissue of Han and Uyghur patients,and the morphological characteristics and ethnic differences of the chin soft and hard tissue of Han and Uyghur adult females of classⅡ~1 were preliminarily evaluated.Methods:According to the inclusion and exclusion criteria,female patients aged 18-35 years old with an average age of 26.5 years in classⅡ~1 were selected from the Affiliated Stomatology Hospital of Xinjiang Medical University from 2015 to 2021(90 Uyghur and Han patients respectively).They were divided into three groups according to the vertical skeletal types:High angle(30 cases),average angle(30 cases)and low angle(30 cases)groups.Relevant variables were measured.Results:(1)The Po-Pos of the Han with high angle was higher than that of the Han with low angle and average angle;The minimum chin thickness,the angle of chin,the ratio of the chin thickness to the chin height and the ratio of the minimum chin thickness to the chin thickness in the high angle group were smaller than those in the average angle group and the low angle group(P<0.05).Further pairwise comparison showed that the chin height,the chin thickness,the posterior chin thickness and B-Bs were statistically different between the high angle group and the low angle group and between the average angle group and the high angle group(P<0.05),Me-Mes was statistically different between the high angle group and the low angle group and between the average angle group and the low angle group(P<0.05),the ratio of anterior and posterior chin thickness,the chin depression,the chin lip angle,the cervical-mandibular angle,LL-Pos and the mentolabial sulcus were statistically different between the high angle group and the low angle group(P<0.05)and Gn-Gns was statistically different between the high angle group and the average angle group(P<0.05).The chin height,the chin depression and the cervical-mandibular angle of the Uyghur with high angle were higher than those of the Uyghur with low angle and average angle;The minimum chin thickness,the ratio of the chin thickness to the chin height and the ratio of the minimum chin thickness to the chin thickness in the high angle group were smaller than those in the average angle group and the low angle group(P<0.05).Further pairwise comparison showed that the chin thickness,the posterior chin thickness,the angle of chin,the chin lip angle,LL-Pos and B-Bs were statistically different between the high angle group and the low angle group and between the average angle group and the high angle group(P<0.05),Po-Pos was statistically different between the high angle group and the low angle group and between the average angle group and the low angle group(P<0.05)and the ratio of anterior and posterior chin thickness and the mentolabial sulcus were statistically different between the high angle group and the low angle group(P<0.05).(2)In the low angle group,there were significant differences in the angle of chin,cervical-mandibular angle,soft tissue chin angle and Me-Mes between the two ethnic groups(P<0.05).In the average angle group,there were significant differences in the height of chin,LI-LL and Me-Mes between the two ethnic groups(P<0.05).In the high angle group,there were significant differences in the ratio of anterior to posterior chin thickness,the angle of chin,LL-Pos and Po-Pos between the two ethnic groups(P<0.05).(3)The positive correlation between FH/MP and B-Bs,Po-Pos,the cervical-mandibular angle,the chin depression,the chin lip angle,the chin height,the ratio of anterior and posterior chin thickness and LL-Pos were found in Han and Uyghur(P<0.05).The mentolabial sulcus,the posterior chin thickness,the chin thickness,the ratio of the chin thickness to the chin height,the angle of chin,the minimum chin thickness and the ratio of the minimum chin thickness to the chin thickness were negatively correlated with FH/MP in Han and Uyghur(P<0.05).Conclusion:(1)Han and Uyghur adult females of classⅡ~1 have different the chin soft and hard tissue morphology in different vertical skeletal types.(2)Han and Uyghur adult females of classⅡ~1 have certain differences in the same vertical skeletal types.(3)There is a correlation between the chin soft and hard tissue morphology of different vertical skeletal types and the vertical skeletal types in Han and Uyghur adult females of classⅡ~1.