A Study On The Morphological Changes Of The Chin In Angle ? Type 1 Cases With Different Thickness Of The Chin

Objective:To compare the morphological differences of soft tissue chin before and after treatment with Class ? division 1 malocclusion,and to discuss the influence of thickness of soft tissue chin has an effect on the morphological changes of soft tissue chin.Materials and Methods:select 100 female?18 to 35years?,take lateral cephalograms,measure the thickness of the soft tissue chin,and establish the classification stand ard of the thickness of the soft tissue chin.Step 2 60 female patients with Class ? division 1 malocclusion were selected.The lateral cephalograms before and after treatment were collected,to measure the thickness of the soft tissue chin before treatment.Then,according to the classification standard established in step 1,they were divided into groups,and the measurement indexes related to the chin soft tissue before and after treatment were measured.Results:1 The measured values of chin soft group thickness of 100 subjects meet the normal distribution.Therefore,the obtained chin soft group thickness is arranged from small to large.The samples?P₂₅ are thin chin group,the samples((P₂₅-P₇₅)are balanced group,and the samples?P₇₅ are thick chin group.Then,60 subjects are grouped according to the results:the chin soft group thickness?8.87mm is defined as thin chin group,the chin soft tissue thickness?8.87-11.00?mm is defined as balance chin gruop,and the chin soft tissue thickness?11 mm is defined as thick chin gruop.2 According to the criteria of result 1,the group was divided and the research was carried out.The results showed that the and the angle of mentolabial groove was higher than that in the balanced and thick chin groups,the difference was statistically significant(The difference was statistically significant?P<0.05?.The comparison of three groups after treatment showed that the depth of mentolabial groove in the thin chin group was smaller than that in the thick chin group?P<0.05?.The comparison of the three groups before and after treatment showed that the depth of mentolabial groove,the inclination angle of mentolabial groove and the convex angle of the face were all decreased,and the soft tissue angle of the face and the lower angle of the force were increased.Conclusion:there are differences in Chin shape of soft tissue in women with different thickness of angle's ?¹.Compared with the other two groups,the change of Chin shape in the group with thinner chin after treatment is more obvious and objective.