A Comparative Study Of The Changes Of Thehard And Soft Tissue Before And After Orthodontic Treatment Of Skeletal Class Ⅲ Malocclusion

Objective:(1)Investigate the effect of orthodontic camouflage therapy on the soft and hard tissues of in adult skeletal class Ⅲ malocclusion(2)to understand the correlation between soft and hard tissue changes afterorthodontic camouflage treatment of adult skeletal class Ⅲ malocclusion dislocation dental deformity.(3)to further understand the differences in the treatment of adult skeletal class Ⅲ malocclusion dislocation orthodontics with micro-implant implantation and traditional Ⅲ mandibular traction;To understand the differences in indications between the two.Methods:17 adult patients with permanent dentition skeletal class Ⅲ malocclusion dislocation and independent selection of orthodontic camouflage therapy were selected in the People’s Hospital of Guangxi Zhuang Autonomous Region from 2012 to 2019,and-7°≤ANB≤-1°(-3.85±1.26),aged 18-29 years(20.8 ±3.26 years old),male 7 cases,female 10 cases.The technique of straight arch correction was used,7 cases were combined with micro-implant support,9 cases were combined with Ⅲ mandibular traction,and 1 cases were not cooperated.Using the SPSS23.0 statistical software,the T test was used to analyze and compare the measurement value of the X-Ray head shadow of the soft and hard tissue before and after the correction,and the independent sample T test compared the difference between the groups before and after the correction.The correlation between the changes of soft and hard tissue before and after correction was analyzed by Pearson correlation analysis method,and the difference was statistically significant with P <0.05.Results:(1)In 17 cases of adult bone type dislocation,The sagittal Ⅲ of the upper mandible was improved,the SNA increased,the SNB decreased,and the ANB increased,and the difference was statistically significant before and after the correction(P< 0.05).The U1-SN of anterior teeth increased,and the difference before and after L1-MP decreased statistically significant(P<0.05).(2)In 17 cases,the lateral appearance of soft tissue was improved after orthodontic camouflage treatment of skeletal classⅢ malocclusion in adults: the increase of H angle after correction,the decrease of chin lip groove,the increase of Li-E distance,the decrease of Ls-E distance,and the statistically significant difference before and after correction(P<0.05).(3)In 17 cases,there was a correlation between soft and hard tissue changes before and after the treatment of bone ⅲ in adults: nasal lip angle was negatively correlated with U1-SN,positive correlation with U1-L1(P<0.05);upper lip convex was positively correlated with SNB and lower anterior lip tilt(P<0.05);upper lip Convex and There was a positive correlation between the lip tilt of the anterior teeth(P<0.05),and the of the chin lip groove was positively correlated with the lip tilt of the lower anterior teeth,and negatively correlated with the SNA angle(P<0.05).(4)17 cases of adult bone Ⅲ type wrong dental orthodontic camouflage treatment combined with micro-implant support group and the combination of Ⅲ maxillary traction Group to correct the change of chin lip groove morphology and lower anterior teeth lip tilt difference is statistically significant(P<0.05);compared toⅢ maxillary traction,mandibular MIA can be used in ANB angle smaller,lower anterior teeth more tongue-leaning And SN-MP are the cases of high angle bone surface,and have advantages in the control of the tilt degree of the lower anterior teeth and the improvement of the chin lip groove.Conclusion :(1)adult skeletal class Ⅲ malocclusionorthodontic camouflage treatment can make the upper mandible sagittal to the non-modulation to improve,vertical and non-modulation to be controlled,the appearance of the landscape improved;(2)adult skeletal class Ⅲ malocclusion orthodontic camouflage treatment needs to reasonably choose the indications,according to its jaw sagittal,vertical non-adjustment and support needs for the correction design and support options,but also to fully consider the individual characteristics of patients and the need for correction,in order to obtain both doctors and patients are satisfied with the correction effect and positive side appearance improvement;(3)There was a correlation between the changes of soft tissue and the change of hard tissue after orthodontic camouflage correction in adult skeletal class Ⅲ malocclusion.The nasal lip angle is affected by the lip tilt of the anterior tooth,the angle of the upper and lower anterior teeth(positive correlation),the upper lip convex is affected by the lip tilt of the anterior teeth(positive correlation),the lower lip convex is affected by SNB,the lip tilt of the lower anterior teeth(positive correlation),The chin lip groove was affected by the change of lip tilt(positive correlation)and SNA angle(negative correlation)of the lower anterior teeth.(4)adult skeletal class Ⅲ malocclusion orthodontic camouflage treatment combined with the mandibular cheek shed MIA implantation in the lower anterior teeth lip tilt control,chin lip groove improvement than the traditional combination of Ⅲ mandibular traction correction has more advantages,and the mandibular cheek shed area with MIA implantation indication is more extensive.