The cephalometric study of korean mandibular angle

The contour of mandibular angle is important for facial esthetics in the oriental population, because the wide and square face is thought to have had an unhappy life. A prominent mandibular angle produces a characteristics quardrangle, coase, and muscular appearance. So, uni- or bi-lateral mandibular angle reduction is usually performed. However, there is little guideline for bi-lateral angle reduction. So, this study was to investigate the pattern of Korean mandibular angle for bi-lateral mandibular angle reduction as guideline. This study was included 66 adult men and women over 19 years old who are having the normal mandibular angle. We measured the posterior border, angle, and inferior border of mandible using cephalometric view. The results of study was as followed : 1. The ratio of posterior mandible was 96.6, 97.3% in male, and 103.0, 106.0% in female. 2. The ratio of mandibular angle(R1-Go/R1-R2) was 120.2% in male, and 117.3% in female. 3. The ratio of inferior mandible(D5, 6, 7, E, F, G/D4) was 97. 3, 90.9, 79.5, 65.2, 57.8, 46.9% in male, and 98.5, 91.2, 80.5, 67.6, 59.1, 50.2 % in female. The results of this study should be useful to decide accurate amount of reduction.

Compensation of female adults with openbite tendency / 대한치과교정학회지

The purposes of this study were to observe the compensation pattern of human female adults with openbite tendency and to provide the decision criteria of the diagnosis and treatment planning for those patients. Fifty patients with anterior openbite and fifty-five patients without anterior openbite patients were selected as a control and a test group. ODI of the all patients was below 66. Mean ages of the control and the test group were 23.88+/-4.53 and 24.7+/-6.20 years, respectively. Lateral cephalograms were taken and forty-one variables were measured. To identify the morphological differences between the groups, statistical analyses were performed. Statistically significant differences were found in the measured variables of lower face height, N-Me, ANS-Me, ANS-Me/N-Me ratio, Mx1-SN, Mx1-FH, Mx1-NA(mm), Mx1-APo, PP to Mx6, Mn1-NB(degree), Mn1-NB(mm). The test group showed decreased lower face height, N-Me, ANS-Me, ANS-Me/N-Me ratio, more uprighted and retruded maxillo-mandibular incisors. Overeruption of the maxillary first molar was found in the control group.

Morphological differences between functional and skeletal anterior cross-bite patients / 대한치과교정학회지

The purpose of this study was to compare the dento-skeletal characteristics between functional and skeletal anterior cross-bite patients. Twenty-eight functional anterior cross-bite patients and thirty-one skeletal anterior cross-bite patients were selected as a test and a control group. Mean ages of the test and the control group were 9.6+/-1.8 and 9.8+/-1.9, respectively. Lateral cephalograms were taken. Forty-nine cephalometric variables were measured and statistical analysis was performed to find the morphological differences between the groups. Statistically significant differences were found in the cephalometric variables of cranial deflection, maxillary depth, ANB, convexity, NPo-AB, APDI, Mx 1-SN, Mx 1-NA angle, Mx 1-NA, Md 1-NB angle and Md 1-NB. The test group showed more Class III growth potential, more protruded maxilla, lesser maxillo-mandibular difference, more uprighted and retruded maxillary central incisor, more labially tipped and protruded mandibular central incisor.