| Objective:The purpose of this study was to evaluate the change of soft-tissue profile esthetics in adult patients with high-angle class II division 1 malocclusion and with tooth extraction (four the first premolar) by orthodontists and adult patients, and to find out the differences between the different people. Selected the thirty high-score patients in evaluation outcome, measured their pre-and post-treatment cephalometric X-rays, and found out the cephalometric indexes related the profile esthetics. It will provide reference and base for clinical planning and effect predicting.Methods:1.The first part was the evaluation of the change of soft-tissue profile esthetics in adult patients with high-angle classⅡdivision 1 malocclusion by orthodontists and adult patients. Eighty-four patients (41 males and 43 females) were selected according to some standards. Traced the soft-tissue silhouettes of pre-and post-treatment cephalometric X-rays, and evaluated that using a visual analogue recording scale (VAS) by 30 orthodontists and 50 adult patients. Compared the scores between orthodontists and adult patients.2. The second part was the analysis of the soft and skeletal tissue in high-score patients and to find out the sensitive indexes related the change of the profile esthetics. Measured the lateral cephalometric radiographs of the high-score patients. SPSS 16.0 software was used to compare the differences of the measurements, and analyzed the scores and the change of soft-tissue indexes by Regression, in order to find out the sensitive indexes related the change of the profile esthetics.Results:1.The results of the first part:the score of the orthodontists was 63.34±24.405, higher than the score of the adult patients 53.51±28.769. Their frequencies were separately 75 and 65. Twenty-eight samples of orthodontists and 25 samples of adult patients was the same to the 30 high-score samples. The distribution trends of scores for high-score samples evaluated by orthodontists and adult patients were basically consistent.2.The results of the second part:(1) There were many measurements of the soft-tissue which changed statisticly in high-score samples:The distance of upper lip and lower lip to E-line,the inclination and the protrusion of upper lip and lower lip significantly diminished (P<0.001). Nasolabial angle increased (P<0.001); the inclination of the mentolabial sulcus increased (P<0.01); the protrusion between lip and chin decreased (P<0.05); the decrease of angle of convexity was significant (P<0.05);the opening degree decreased to the nomal range (P<0.001)(2) There were many measurements of the hard-tissue which changed statisticly in high-score samples, mainly in the sagittal direction:SNA and ANB decreased (P<0.05); chin development degree increased 0.933mm (P<0.05);but the position of mandible (Pog-S) and the length of mandible (Pog-Go) had no significant change after treatment (P>0.05).(3) In high-score samples, the distance between lower incisor and mandibular plane diminished (P<0.05);the vertical changes of upper incisor,maxillary molar and mandibular molar were not statistic (P>0.05); U1/SN,U1/NA and OJ all significantly decreased (P<0.001). U1-NA,L1/NB,L1-NB and IMPA also decreased (P<0.01).(4) In high-score samples, the linear regression equation was Y=54.735-2.656X1-2.310X12+2.268X13+0.650X4+0.274X7. The sensitive indexes were X1—Ls-E; X12-Li-NS-Pos; X13-Gs-Prn-Pos; X4—A'-Ls-FH; X7—Z angle.Conclusions:1. The esthetic requirement between orthodontists and adult patients was different. Adult patients required higher degree of esthetic improvement. The distribution trends of VAS scores evaluated by the two teams for high-score samples were basically consistent, and the improvement after treatment was well evaluated. 2. The soft-tissue profile of adult patients with high-angle classⅡdivision 1 malocclusion was well improved after upper and lower first premolar extraction treatment. Upper and lower lips were markedly adducted, their inclination and protrusion decreased. The angle between lips and chin diminished. The relationship between lips and chin was more coordinated. The Z angle and inclination of the mentolabial sulcus increased, So that curly lower lip extended, mentolabial sulcus stretched and looked more beautiful. Nasolabial angle increased and convexity angle decreased, making the face upright.3. In clinical, we should pay attention to the control of vertical anchorage for adult patients with high-angle classⅡdivision 1 malocclusion. Prevent the vertical elongation of the mandibular molars. Control the inclination of occlusal plane and mandibular plane. Prevent the mandible following the rotation. Ensure the surface height to be stable.4. Adult patients have no growth potential basically. In treatment, the length and position of mandible,the height of mandibular ramus had no statisticly change. The Orthodontic treatment effects were essentially dental compensation. Maxillary molar anchorage must be strictly strong, mandibular molar anchorage can be mild. Prevent the mandibular incisors to be over-adducted.5. The sensitive indicators which affect soft tissue profile improvement in adult patients with high-angle classⅡdivision 1 malocclusion mainly were the protrusion of upper lip (Ls-E); the protrusion of lower lip and chin; angle of convexity; the inclination angle of upper lip and Z angle. The protrusion of upper lip (Ls-E); the protrusion of lower lip and chin and angle of convexity were more sensitive.
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