• The korean journal of orthodontics
• /
• v.34 no.5 s.106
• /
• pp.408-416
• /
• 2004

The purpose of this study was to investigate the preference of Vertical Lip-Chin Ratio (=Sn-Stm/Stm-Me', hereafter VLCR) in Koreans. The assessors consisted of 44 dentists (male 22, female 22) and 430 lay persons (male 303, female 127). The survey was performed using a questionnaire asking the order of preference. The profiles presented in the questionnaire were based on the profiles of two males and two females, each morphed according to the VLCRs of 1/1.8, 1/1.9, 1/2.0. 1/2.1, 1/2.2. The results were as follows: The difference between males and females. and the difference betwwen dentists and lay persons in the preference of VLCR were not statistically apparent. The most Preferred VLCR was 1/1.9, and the least preferred VLCR was 1/2.2, These results Indicate that the preferred VLCR is smaller than the previously reported VLCR ratios based on the cephalometric evaluation of samples with favorable facial esthetics.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.36 no.2
• /
• pp.94-99
• /
• 2010

The purpose of this study was to examine the soft tissue changes in skeletal class II patients after mandibular advancement by bilateral sagittal split ramus osteotomy (BSSRO). In Asian population, the incidence of skeletal class II malocclusion is lower than that of skeletal class III malocclusion unlike the caucasians. This study was conducted to figure out the ratio at which hard tissue and soft tissue changes after mandibular advancement by analyzing cephalograms of 13 patients that have undergone the mandibular advancement surgery. As a result, change ratios of Li, B', Pog' according to the movement of li, B, Pog were found to be 0.59, 1.06, 0.82. Also, vertical height of vermilion zone (Si-Vb) and lower lip and chin (Si-Me') were measured to evaluate vertical changes. Vermilion zone showed tendency to decrease by 1.02 mm on the average postoperatively, whereas vertical length of lower lip and chin showed tendency to increase by 3.57 mm on the average.

• The korean journal of orthodontics
• /
• v.43 no.4
• /
• pp.168-177
• /
• 2013

Objective: In this study, we aimed to examine the relationship between chin deviation and the positional and morphological features of the mandible and to determine the factors that contributed to chin deviation in individuals with a unilateral cleft lip and palate (UCLP). Methods: Cone-beam computed tomography (CBCT) images of 28 adults with UCLP were analyzed in this study. Segmented three-dimensional temporomandibular fossa and mandible images were reconstructed, and angular, linear, and volumetric parameters were measured. Results: For all 28 individuals, the chin was found to deviate to the cleft side by 1.59 mm. Moreover, among these 28 individuals, only 7 showed distinct (more than 4 mm) chin deviation, which was toward the cleft side. Compared to the non-cleft side, the mandibular body length, frontal ramal inclination, and vertical position of the condyle were lower and inclination of the temporomandibular fossa was steeper on the cleft side. Furthermore, the differences in inclination of the temporomandibular fossa, mandibular body length, ramus length, and condylar volume ratio (non-deviated/deviated) were positively correlated with chin deviation. Conclusions: UCLP individuals show mild chin deviation to the cleft side. Statistical differences were noted in the parameters that represented positional and morphological asymmetries of the mandible and temporomandibular fossa; however, these differences were too small to indicate clinical significance.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.20 no.4
• /
• pp.284-290
• /
• 1998

The purpose of this study was to assess the soft tissue changes using twenty skeletal class III malocclusion patients who treated with bimaxillary surgery for the correction of dentofacial deformities. Patients were divided into two groups. One was impaction and advancement of maxilla with mandibular set-back (Group 1), the other was downward and advancement of maxilla with mandibular set-back (Group 2). Preoperative and postoperative one year cephalometric data were analyzed and compared. Results obtained were as follows: 1. The ratio of horizontal changes of soft tissue to hard tissue at Nt to ANS, Ls to UI, Li to LI, sPog to Pog were 1:0.60, 1:0.79, 1:0.47, 1:0.63 in group 1 respectively, and 1:0.59, 1:0.48, 1:0.83, 1:1.09 in group 2 respectively. Soft tissue changes were highly predictable at the upper lip, lower lip, and chin area. 2. The ratio of vertical changes of soft tissue to hard tissue at Nt to ANS, Li to LI were 1:0.72, 1:0.06 in group 1, and others showed no statistically significant difference. 3. The ratio of horizontal changes of Ls to hard tissue movements at LI(h) was 1:-0.82 in group 1 and at UI(h), LI(h) were 1:0.48, 1:0.01 in group 2. These ratios of group 1 were greater than those of group 2. 4. The direction of horizontal change of Li was the same as that of hard tissue change. The ratio of horizontal changes of Li to LI was 1:0.47 in group 1 and others showed no statistically significant difference. 5. The changes of upper lip thickness and length were -1.6mm, -1.4mm in group 1, and -1mm, -2.7mm in group 2. 6. The ratios of thickness of upper lip to ANS, UI, LI were 1:-0.83, 1:-0.37, 1:0.11 in group 1. There was similar trend in group 2, and there were no statistically significant difference. These results suggest that prediction of changes in soft tissue of upper lip, lower lip, and chin were 79%, 47%, and 63% in group 1, and 48%, 83%, and 109% in group 2. There was a tendency to decrease in thickness and increase in length of the upper lip.

• The korean journal of orthodontics
• /
• v.30 no.3 s.80
• /
• pp.355-365
• /
• 2000

The treatment plan for orthognathic surgery must be based on accurate predictions, and this can be produced the most esthetic results. Treatment of prognathic mandible in adult is usually orthognathic surgery using mandible set back, but mandible with retruded chin point is needed additional chin augmentation. In this case, the directions between mandible and chin point are different therefore, the prediction of soft tissue reactions must be modified. In this study, we materialize the patients who was taken orthognathic surgery due to prognathic mandible, 11each(Group A) was taken only Bilateral Sagittal Sprit Ramus Osteotomy (BSSRO), 9each(Group B) was taken additional advancement genioplasty. The lateral cephalometric radiography taken 8 months later after orthognathic surgery by this patients were used. The results of this study were as follows : 1. The profile of lips was favorable after surgery due to upper lip to I-line became prominent and lower lip tc E-line was retruded. 2. In both group, upper lip moved posteriorly and nasolabial angle was increased. 3. The ratio of the soft tissue profile change in POGs point to skeletal B point movement was $84\%$ in group A and $66\%$ in group B, and there was statistical significance between group A and group B. 4. Vertical movement of hard tissue points is decreased in group A.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.18 no.1
• /
• pp.87-108
• /
• 1996

This study was intended to perform cephalometric analysis of the facial soft tissue profile after surgical correction of skeletal Class III malocclusion after SSRO in 29 patients (Males 12, females 17). Lateral cephalograms were taken in centric occlusion before and immediate, long term after surgeries. 1. Counter-clockwise rotation of mandible was observed after the surgery, average relapses of mandibular set back were 1.23-1.28mm. The net effects of the mandibular set-back after surgeries were 81.7-82.2%. Because these relapse tendencies may reduce the effects of the surgical outcomes, surgeon must consider these net before the surgical treatment planning. 2. The ratio of horizontal changes of hard tissue to soft tissue at lower lip, mentolabial sulcus, pogonion were 72.7-93.7%, 100.3%, 99.1-102.1% respectively. There were little changes at upper lip position anteroposteriorly. 3. The relationship of upper and lower lips were improved after surgery. Lower lip was posteriorly repostioned and upper lip was flattend and elongated in conjunction with deepening of inferior lobial sulcus. But profile of chin was still prominent after surgery. 4. Hard tissue horizontal changes and tissue vertical changes were significantly correlated with each other and there were reverse correlations with hard tissue vertical changes and soft tissue horizontal changes.

• The korean journal of orthodontics
• /
• v.47 no.2
• /
• pp.87-99
• /
• 2017

Objective: The aims of this study were to measure and compare the facial dimensions of the Miss Korea pageant contestants and a selected group of women from the general population by using three-dimensional (3D) image analysis, as well as to compare various facial ratios to the golden ratio within each group. Methods: Three-dimensional images of 52 Miss Korea pageant contestants (MK group) and 41 young female adults selected from the general population (GP group) were acquired. Fifty-four variables and ratios were measured and calculated. Intergroup comparisons were performed using multivariate analysis of variance. Results: Compared to the GP group, the MK group showed greater total facial height and eye width, lesser lower-facial height, and lesser facial, lower-facial, and nasal widths. Moreover, compared to the GP group, the MK group had more protruded noses with greater nasolabial angle, greater vertical curvature of the foreheads, lesser horizontal curvature of the cheek, and lesser lower-lip-and-chin volume. Conclusions: The MK group had longer faces but smaller lower lips and chins than did the GP group. The golden ratio was not matching the current facial esthetic standards. These data might be beneficial for treatment planning of patients undergoing orthognathic and plastic surgeries.