• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.6
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• pp.421-425
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• 2012

Purpose: The aim of this study is to compare the soft tissue changes of the midfacial area at the repose position and the natural smiling position for the improvement of evaluation and planning in the orthognathic surgery. Methods: The total of 30 subjects, 15 male and 15 female, were included in this study. The metal point landmarks were placed at the cheek, orbital rim, subpupil, and nasal base. The movements of the landmarks were evaluated at the repose position and smiling position in the lateral and posteroanterior cephalograms. Paired t test and correlation analysis were used for the evaluation of the soft tissue changes statistically. Results: In the lateral cephalograms, the cheek point (4.49 mm in female, 4.87 mm in male) showed the most distant movement. All points presented significant movements, except the orbital rim and nasal base point in male. Cheek point presented significant positive correlation between the horizontal and vertical change in male. Subpupil point presented significant positive correlation between horizontal and vertical change in both male and female. In the posteroanterior cephalograms, the nasal base point (5.41 mm in female, 6.30 mm in male) showed the most distant movement. Subpupil point and nasal base point presented significant movements in both female and male. Nasal base point presented significant negative correlation between the horizontal and vertical change in both male and female. In the lateral and posteroanterior cephalograms, the positional changes of all points presented significant positive correlation with each other in both female and male. Conclusion: The cheek point in the sagittal view and the nasal base point in the frontal view showed the most distant movement on smile. In the sagittal view, the subpupil point and cheek point moved anteriorsuperiorly on smile. In the frontal view, the nasal base points moved laterosuperiorly on smile. In both the sagittal and frontal view, the positional changes of all point were highly correlated to each other. These results may be used in the soft tissue references for the treatment planning of the dentofacial deformity patients.

• The korean journal of orthodontics
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• v.27 no.4 s.63
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• pp.569-584
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• 1997

The present study assessed the effects of Rapid Maxillary Expansion on head posture and hyoid bone position. For this study, 32 Angle's class III patients - hellman 3c $\~$ adult stage, mean age 12y9m - were selected and divided into two groups, A,B according to craniocervical angulation. Craniocervical angulation Increased in Group A and decreased in Group B after the therapy. And 23 Angle's class I persons $\~$ same hellman stage, mean age 12y7m $\~$ were selected (or the control group. Cephalometric analysis of skeletal pattern, pharyngeal space, head posture, hyoid bone position was performed. The results were as follows, 1. Comparison of skeletal pattern and pharyngeal space 1) All two groups(A,B) had Mandibular plane inclined inferiorly and no pharyngeal space change was obseved after RME therapy 2) Skeletal pattern and pharyngeal space of Group A, B were normal before and after treatment. 2. Comparison of head posture 1) Craniocervical angulation of Group A was increased after treatment. That of Group B was decreased and mandibular plane was inclined inferiorly after treatment. 2) Before treatment, craniocervical inclination was normal in Group A but larger than normal in Group B. After treatment, all two groups(A, B) had normal craniocervical angulation. 3. Comparison of hyoid bone position 1) After treatment, long axis of hyoid in Group A, B was not changed. Antero- posteriorly, hyoid position was changed posteriorly in Group A but no change was founded in Group B after treatment. Vertically, hyoid bone position were not changed in two groups except increase in APHFH in Group A after treatment 2) Long axis of hyoid bone was normal in Group A, B before and after treatment. Anteroposteriorly, hyoid bone position was more anterior than Group B, C before treatment but all the position of two groups had normal position after treatment. Vertical position of hyoid bone was normal in all two groups before and after treatment.

• Journal of Oral Medicine and Pain
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• v.32 no.3
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• pp.293-303
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• 2007

The purpose of this paper is to evaluate if there is a relationship between anterior disc displacement without reduction and development of anterior open bite, and a relation between occurrence of open bite and occlusal appliance therapy. In general, the statistically significant differences were found between the Group 1 and 2 and normal mean group. The variables that represent mandibular size and form, showed a statistical significance in all 3 groups. Also 3 groups patients had a smaller ANB, a larger FMA than normal mean group. When we compared the 3 groups with respect to all cephalometric measurements by One-way analysis of variance (ANOVA), group 1 and 2 patients had a larger FMA, a larger SN to mandibular plane angle, a larger maxillomandibular plane angle, a larger occlusal plane to mandibular plane angle, a smaller total posterior facial height/total anterior facial height(%), and a larger gonial angle than group 3. The statistically significant differences were not found between the Group 1 and 2, and skeletal patterns were similar. Thus, morphologic features of patients with vertical discrepancies may represent a risk factor for the development of anterior open bite with or without occlusal appliance treatment. In case of patients with vertical discrepancy, we may have to be more careful when inducing a change of the vertical dimension.

• The korean journal of orthodontics
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• v.27 no.1
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• pp.65-78
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• 1997

This study was carried out in order to determine soft tissue response to incisor movement and mandibular repositioning and to determine feasibility of predicting vertical and horizontal changes in soft tissue with hard tissue movement. For this study, cephalometric records of 41 orthodontically treated adult females who had Angle's Class II division 1 malocclusion were selected and stepwise multiple regression analysis was employed. Following conclusions were obtained by analysing the changes of soft tissue and hard tissue before and after treatment. 1. Hard tissue measurements that showed significant changes before and after treatment were horizontal and angular changes of maxillary incisor, horizontal,vertical and angular changes of mandibular incisor, overjet, overbite, interincisal angle, mandibular repositioning, A,B, skeletal convexity and soft tissue measurements that showed significant changes were horizontal, thickness and angular changes of upper lip, horizontal and angular changes of lower lip, interlabial angle, nasolabial angle labiomental angle, Sri, Ss, Si and soft tissue convexity(P<0.05). 2. All Soft tissue measurements changed significantly before and after treatment had between one and four hard tissue independent variables at statistically significant level, indicating that all soft tissue changes were direct relationship with hard tissue changes 3. Ova jet, horizontal change of maxillary incisor, horizontal change of maxillary root apex and horizontal change of pogonion entered into prediction equations most frequentely indicating that they were more significant variables in prediction of vertical and horizontal changes in the soft tissue with treatment, but vertical changes of mandibular incisor not entered any prediction equations, indicating that it was not considered a good predictor for soft tissue changes with maxillary incisor retraction. 4. Horizontal and vertical changes in subnasale were found to have most independent variables, significant at the 0.05 level in prediction-equations(${\Delta}$Sn(H):Ur, Is(H), Pg(H), UIA,${\Delta}$Sn(V): Is(H), Pg(H), overjet, A), indicating that subnasale changes are influenced by complex hard tissue interaction. 5. Multiple correlation coefficient($R^2$) of the soft tissue prediction equations ranges from 0.2-0.6.