The Related Factors Of Soft Tissue Changes In Adult Female After Orthodontic Treatment

With the social development and change,more and more orthodontic patients,especially female adult patients pay more attention to the beauty of the whole face.Nowadays,orthodontics chase not only on stable teeth,good function but also on aesthetic of facial soft tissue.The goals of the adult female patients are very clear and their psychological needs are very high(85% of adult female patients' motive are improve dating,marriage and job interview successful rate).The adult female patients also have high attention to their own facial morphology change.In clinical practice,more and more adult female orthodontic patients complain that their temple and cheek sag become more obviously and the cheekbones are more prominent during the orthodontic process.These problems have been summarized by patients as " bracket face" and widely spread on the internet.Therefore,it causes the doubt and panic of the orthodontic patients,and even become the conflict point between doctors and patients.The face is anatomically composed of soft tissues such as fat and muscle,and hard tissues such as bone and teeth.And the changes in hard tissue or soft tissue can affect facial shape.Studies have foundthat 10 years of aging changes in facial bones of adults(ages 22-33)is only 1.5 mm,so there are few skeletal changes during the adult orthodontic treatment,the main changes happened in facial soft tissue.However,the study on the changes and regularity of natural aging in the short term of adult facial soft tissue morphology has few reported in the literature.At present,most studies believed that no matter extraction or nonextraction treatment,adult facial soft tissue morphology has a certain trend to change during orthodontic treatment.However,the reasons for this change are due to orthodontic treatment or its own aging change,which is not reported in the relevant literature.In the preliminary study on the change of facial soft tissue of adult males and females,28 non-orthodontic adult males(ages 26.2±2.20)and 33 non-orthodontic adult females(ages 25.2±2.23),after factors such as age,BMI,occlusion and attitude differences were excluded,it was found that the males and females overall facial area change was 0.06 mm and 0.02 mm in 12 months,and the change in the total area of the face was 0.09 mm and 0.05 mm in 24 months.There was no significant difference in the total area of the face between 12 months and 24 months.There was no significant change in the total area of the face in the two years of the absence of orthodontic adults(ages 25.66±2.22).In three-dimensional preliminary study that the effect of orthodontic treatment on facial soft tissue in adult females,no matter extraction or nonextraction treatment,adult female facial soft tissue after orthodontic below average by about 2 mm,each area of the face was reduced by an average of 1 mm.After orthodontic treatment,the facial soft tissue of adult female has a certain negative change,and there is no significant difference between extraction or nonextraction patients.Based on the previous study,this research attempts to use 3dMD stereophotography technology and 3D digital model scanner to measure the facial features such as occlusal height and arch width of 52 adult female orthodontic patients(24 extraction,28 nonextraction)before and after orthodontic treatment.In order to find out whether the teeth factors have related to facial features? And is the change of occlusal vertical height and the arch width in the orthodontic process to be related to the change of facial softtissue in adult female? Therefore,this study tries to provide a theoretical basis for the influence of orthodontic treatment on the facial soft tissue of adult female,and a more comprehensive and accurate reference for the diagnosis and analysis of orthodontic treatment and the formulation of the treatment plan.Also,try to reduce the risk of facial aesthetics in the orthodontic treatment of adult females and to prevent the medical disputes related to facial soft tissue aesthetics.This study includes the following 3 parts:Part I.Correlation analysis of facial morphological features of adult female to the changes of facial soft tissue after orthodontic treatment.Objective: To explore whether there are some degrees of correlation between the facial morphology of adult female to the three-dimensional change of facial soft tissue after orthodontics.Methods: 52 adult female patients(24 extraction,28 nonextraction,mean ages 24.89±3.67)from the FMMU oral hospital,Department of Orthodontics on April 2014,shooting by 3d MD facial stereophotography system(3d MDface,Atlanta,USA)before the orthodontic treatment for 3D image data,import date to 3-matic STL 9.0 software(Materialise,Leuven,BEL)for calibration and measurement of facial soft tissue landmark.Compare adult female face three-dimensional morphological characteristics between the extraction group and the nonextraction group,and analyze the data of adult female facial soft tissue change after orthodontics in previous studies by using Spearman correlation analysis method.Conclusion: the upper and lower lip of extraction group were more prominent than nonextraction group,while the other facial features were not significantly different between the two groups.There is correlation between short of Sn-Me ' and N '-Me',and small of Sn'Me'/Rt Go'-Lt Go' and N'-Me'/ Rt Zy-Lt Zy and negative change of buccal area(R9).It is suggested that adult female orthodontic patients with wide and short facial features may be more prone to the negative change of buccal soft tissues during the orthodontics,and have "bracket face".Part II.Correlation analysis of the occlusal height change to the changes of facial soft tissue in adult female after orthodontic treatment.Objective: To explore whether there are some degrees of correlation between the occlusal height of adult females to the three-dimensional change of facial soft tissue after orthodontic treatment.Methods: 52 adult female patients(24 extraction,28 nonextraction,mean ages 24.89±3.67)from the FMMU oral hospital,Department of Orthodontics on April 2014,taking X-rays(Finland Orthoceph)to get lateral cephalometric radiographs before and after orthodontic treatment,import radiograph to Onyx 2.6 software(Image Instruments,Chemnitz,Germany),select part measuring project of Steiner analysis,Tweed analysis and Coben analysis.Compare differences of adult female occlusal height changes between extraction group and noextraction group before and after treatments,and analyze the data of adult female facial soft tissue change after orthodontics in previous studies by using Spearman correlation analysis method.Conclusion: ? UI-NA,UI-NA,? LI-NB and LI-NB of extraction group after orthodontics have obvious decreasing,?LI-NB and LI-NB of nonextraction group after orthodontics have obvious decreasing.There was no significant difference between the two groups before and after orthodontics.There is a weak negative correlation relationship between the height change of N-Go and the three-dimensional changes of the facial soft tissue zygomatic arch area(R3),The N-Go height increase may become the risk factor of three-dimensional negative changes of adult female zygomatic arch area(R3).In the orthodontic process of adult females,it is necessary to avoid the use of occlusal height increasing tools or techniques(such as flat bite,bite guard),so as not to aggravate the three-dimensional negative change of facial soft tissue of adult female.Prat III.Correlation analysis of the arch width change to the change of facial soft tissue in adult female after orthodontics.Objective: To explore whether there are some degrees of correlation between the arch width of adult females to the three-dimensional change of facial soft tissue after orthodontics.Methods: 52 adult female patients(24 extraction,28 nonextraction,mean ages 24.89±3.67)from the FMMU oral hospital,Department of Orthodontics on April 2014,using 3shape digital model scanner(3 shape,Copenhagen,DNK)to scan the occlusion model before and after orthodontic treatment,import the data to the 3-matic STL 9.0 software(Materialise,Leuven,BEL)for landmark and measurements.Compare differences of adult female arch width changes between extraction group and noextraction group before and after treatments,and analyze the data of adult female facial soft tissue change after orthodontics in previous studies by using Spearman correlation analysis method.Conclusion: there was no statistical difference of the width of the maxillary canine or first molar between extraction group and nonextraction group.There was no statistical difference arch width change between extraction group and nonextraction group before and after orthodontics.There was no significant correlation between the change of arch width and the three-dimensional change of facial soft tissue.