Effects Of Tooth Extraction And Non-tooth Extraction Correction On The Positive Morphology Of Adult Patients With Class ? Bimaxillary Dental Protrusion

Objective: The effects of tooth extraction and non-tooth extraction treatment on the frontal morphology of patients was compared by measuring the frontal pictures before and after orthodontic treatment for the adults with Angle Class ? bimaxillary dental protrusion.The related changes and their influencing factors of frontal morphology before and after orthodontic treatment were analyzed.Method: 40 adult orthodontic patients with an orthodontic treatment of class I premaxillary dental protrusion in Yijishan Hospital of Wannan Medical College were randomly selected from January 2010 to October 2018.According to whether the first premolar was removed,40 patients were divided into the extraction group(aged 19 to 25 years,mean age 21.15±2.11 years)and the non-extraction group(age 19 to 25 years,mean age 21.75± 2.12 years old).There are 20 samples in each group,10 males and 10 females.The frontal images of 40 patients before and after operation were measured at fixed points.In order to reduce the measurement error,all fixed point measurements are completed by the author independently.The measurement was performed three times in total,measured every three days and the average of three measurements was taken as the definitive data.The correlation changes of twelve measurement indexes were compared before and after treatment in tooth extraction group and non-tooth extraction group :face width/pupil distance,nose breadth/pupil distance,mouth breadth/pupil distance,mandible width/pupil distance,face height/pupil distance,lower facial height/pupil distance,face height/face width,jaw height/jaw width,lower lip length/upper lip length,jaw width/face height,mouth width/mandible width,face width/mandible width,and statistics work was performed at the same time.Microsoft excel software was applied for statistical treatment.Statistical analysis software package(SPSS)version 21.0 was used for static analysis.Paired t test was used for the measurement items in groups before and after orthodontic treatment.Multi-factor independent sample t test was performed on the measured data which among groups before and after orthodontic treatment.When P<0.05,the difference was statistically significant.When P<0.01,the difference was statistically significant.When P> was 0.05,the difference was not statistically significant.Results: The lower facial height/pupil distance and lower facial height/mandible width were increased in non-extraction group increases after orthodontic treatment in this experiment,P < 0.05,the difference was statistically significant,the rest of the measurement(Face width/pupil distance,nose width/pupil distance,mouth width/pupil distance,face height/pupil distance,face height/pupil distance,face height/face width,lower lip length/upper lip length,lower jaw width/face height,mouth width/lower jaw width,face width/lower jaw width)were not statistically significant difference before and after treatment(P > 0.05).2.After treatment,the width of the mouth/pupil distance,the height/pupil distance and the height/mandible width of the tooth extraction group were higher than those before treatment,and the difference was statistically significant(P<0.05).The mandibular width/face height after orthodontic treatment was lower than that before treatment,and the difference was statistically significant(P<0.05).The length of lower lip/upper lip has increased compared with that pre-treatment.(P<0.01).The other variables(face width/pupil distance,nose width/pupil distance,mouth width/pupil distance,face height/pupil distance,face height/face width,mouth width/mandible width,face width/mandible width,and face width/mandible width.) were no statistically significant differences before and after treatment(P>0.05).Group 3.A comparison between extraction group and non-extraction group before orthodontic treatment: there were no distinct effect on statistical significance in face width/pupil distance;nose width/pupil distance;mouth width/pupil distance;mandible width/pupil distance;face height/pupil distance;bottom height/pupil distance;face height/face width;jaw height/jaw width;lower lip length/upper lip length;jaw width/face height;mouth width/mandible width,face width/mandible width differences(P > 0.05);Comparison between tooth extraction group and non-tooth extraction group after orthodontic treatment revealed that lower lip length/upper lip of tooth extraction group was longer than that of non-tooth extraction group,and the difference was statistically significant(P<0.01).Other statistical indexes showed no significant difference in face width/pupil distance,nose width/pupil distance,mouth width/pupil distance,mandible width/pupil distance,face height/pupil distance,bottom height/pupil distance,face height/face width,mandible height/jaw width,mandible width/face height,jaw width/face height,mouth width/jaw width,face width/jaw width,and face width/jaw width(P>0.05).Conclusions:1.There was no significant change in tooth extraction and non-tooth extraction correction of facial width,but there is some influence on the height of the face,extraction is more likely to lead to an increase in facial height than non-extraction.2.Adult orthodontic patients with teeth uncovered by lips and mouth closed difficulty can effectively improve lip shape by tooth extraction treatment.3.Adult orthodontic patients with facial emaciation,protrusion of zygomatic region should be carefully corrected by tooth extraction.The patient should be fully communicated before treatment when the tooth extraction was needed.The doctor should let the patient know the frontal soft tissue morphological changes after orthodontic treatment.