• The korean journal of orthodontics
• /
• 제29권3호
• /
• pp.339-347
• /
• 1999

The purpose of this study was to investigate the variations of the skeletal and dentoalveolar dimensions in relation to vertical facial patterns. Lateral cephalogram of 200 cases (100 cases of male and 100 cases of female, average age of which was 23.2 years) were traced and some measurements of skeletal and dentoalveolar dimensions were measured. The ratio of UAFH/LAFH was employed to classify the samples into groups of excess and short lower anterior facial height. And the comparison between two groups were taken statistacally. The following results were obtained. 1. The dentoalveolar height, lower anterior facial height, lower genial angle, and FMA in the excess-lower-anterior-facial-height group were significantly larger than those in short-lower-anterior-facial-height group. 2. The dentoalveolar height, facial height, ramus height, and Jarabak ratio in the male subjects were significantly larger than those in the female subjects. 3. The UAFH/LAFH ratio showed a significant correlation to upper, lower facial height, AUDH, PUDH, ALDH, PLDH, Lower gonial angle, FMA, and $Bj\"{o}rk's$ Sum.

• The Journal of Korean Academy of Prosthodontics
• /
• 제54권1호
• /
• pp.1-7
• /
• 2016

Purpose: The aim of this study was to evaluate the effect of increased vertical dimension of occlusion on lower facial changes by facial type. Materials and methods: Lateral cephalograms from 261 patients were obtained and classified by sagittal (Class I, II, and III) and vertical (hypodivergent, normodivergent, and hyperdivergent) facial patterns. Retrusive displacement of soft tissue Pogonion and downward displacement of soft tissue Menton were measured in each group after 2 mm of vertical dimension of occlusion was increased at the lower central incisor using a virtual simulation program. The ratio of both displacements was calculated in all groups. The statistical analysis was done by 2-way ANOVA and Post hoc was done by Tukey test (5% level of significance). Results: Retrusive displacement of soft tissue Pogonion in Class III group was statistically different compared to Class I and II, and in vertical facial groups all 3 groups were significantly different (P<.05). Downward displacement of soft tissue Menton showed statistically significant difference between all sagittal groups and vertical groups (P<.05). The ratio of both displacements showed statistically significant difference in all sagittal groups and vertical groups (P<.05), and Class II hyperdivergent group had the highest value. Conclusion: Lower facial change was statically significant according to the facial type when vertical dimension of occlusion increased. Class II hyperdivergent facial type showed the highest ratio after increase in vertical dimension of occlusion.

• Journal of the Korean Academy of Esthetic Dentistry
• /
• 제31권1호
• /
• pp.26-35
• /
• 2022

Patients who miss teeth partially or fully show many changes which make them lose function and esthetics.From the esthetic point of view, loosing teeth makes lower face unharmonized. There are various changes of lower and whole face according as how much change oral cavity is. Restoring the multiple teeth missing properly can make patient's face harmonized. Especially full mouth implant restorations can cause drastic occlusal change affecting masticatory muscles. Because all the muscles are connected closely, the masticatory muscles which is part of lower facial muscles can cause whole muscle change. In full mouth implant restoration case, I will show the whole face muscle change harmonized by meticulous occlusal treatment process. Full mouth restorations installed in right way show whole face muscle changes extending to head and neck muscles.

• The korean journal of orthodontics
• /
• 제33권5호
• /
• pp.323-337
• /
• 2003

This study was performed to establish Korean soft tissue cephalometric norms, to compare the norms between sexes and between races, and then to suggest a guideline to execute orthodontic diagnosis and treatment planning for dentofacial deformities in Korean. Young Korean adults were selected. They were 27 males $(23.8{\pm}2.6-year-old)$ and 20 females $(22.5{\pm}1.7-year-old)$ who had harmonious facial balance. After taking lateral cephalograms under the natural head position which is widely known as a highly reliable and reproducible reference position, films were traced and analysing factors were measured as introduced by Arnett et at. Comparisons were done between male and female groups and between Korean and Caucasian groups using unpaired t-test. From the results it was concluded that Korean male had generally thicker lower facial soft tissue and smaller nasolabial angle, longer facial height, deeper facial depth, and more protrusive lower face than Korean female. From the comparison with Caucasian norms adopted from the research of Arnett et al., both Korean male and female showed longer facial lengths generally except less exposed maxillary incisor, and shorter facial depth than Caucasian counterparts. Also, both races showed similar horizontal position of maxillary structures from TVL (true vertical line), but there were more significant anteroposterior differences of marilla-mandible in Korean groups. These results mean Korean had relatively more retruded mandibular structures from the reference line, TVL. Individuals who had harmonious facial balance showed similar facial angle, more or less 170 degree, regardless of sexes or races.

• The korean journal of orthodontics
• /
• 제26권3호
• /
• pp.247-254
• /
• 1996

This study was performed to evaluate the hyoid bone position and airway in skeletal class III malocclusion and to prove the correlation between airway, hyoid bone position and mandibular position. The sample, considered of 47 class III malocclusion patients for experimmtal group and 52 class I malocclusion students for control group. Twenty three linear and angular measurements about hyoid bone position, airway size, mandibular position were taken from the lateral cephalograms. The differences between skeletal class III malocclusion group and normal occlusion group were compared and the correlation were evaluated statistically. The results obtained were as follows, 1. There were significant difference in S-APH, A-APH, N-APH, LAH-PBR, AA-PNS, PNS-ad between class I and class III malocclusion groups. 2. The hyoid bone was more anteriorly positioned in class III malocclusion group than class I malocclusion group and skeletal airway size in class III malocclusion group was smaller than class I malocclusion group. 3. There were significant difference in several measurements especially vertical and angular measurements of hyoid bone position and airway size between male and female. Usually the measurements in male were larger than female. 4. There were no significant correlation between hyoid bone position and airway size also airway size, and didn't showe significant correlation with mandibular position, 5. S-APH showed negative correlation with Wits appraisal and A-APH, N-APH showed positive correlation with Wits appraisal. On the contrary vertical measurements of hyoid bone position showed positive correlation with lower facial height.

• The korean journal of orthodontics
• /
• 제25권5호
• /
• pp.613-625
• /
• 1995

The purpose of this study was to investigate the degree of relapse following orthognathic surgery and the relationship between preoperative state and the methods of orthognathic surgery in skeletal Class III patients. Thirty-one patients were selected(17 men, and 14 women) for this study, who had received orthognathic surgery(20 one jaw surgery, and 11 two jaw surgery). The mean age was 22.5 years. Their lateral cephalograms, that were taken preoperatively, immediate postoperatively and follow-up over one year, were traced and analysed. The results were as follows : 1. In two jaw surgery, mandibular length, lower facial height and lower lip length were 4.24mm, 4.64mm and 4.13mm longer than in one jaw surgery, respectively But in two jaw surgery, overjet was 3.13mm shorter than in one jaw surgery. 2. In one jaw surgery, mandible was moved back $8.95\pm4.45mm$ at B point. In two jaw surgery, maxilla was moved forward $5.15\pm3.46mm$ and mandible was moved back $7.24\pm9.11mm$ at B point. 3. Between postoperation and follow-up over one year, A point, A' point, Pn and Sn were moved backward 1.02 $\pm$ 2.14mm, $1.73\pm1.63mm,\;1.05\pm1.48mm\;and\;1.55\pm1.37mm$ in two jaw surgery, respectively. 4. Between postoperation and follow-up over one year, in one jaw surgery, B point was moved forward $2.58\pm4.22mm$ and B' point was moved forward $1.95\pm4.39mm$. In two jaw surgery, B point was moved forward $0.65\pm2.88mm$ and B' point was moved forward $0.19\pm3.32mm$. In one jaw surgery, relapse rate was $28\%$ at B point and $24\%$ at B' point, whereas in two jaw surgery, relapse rate was $8\%$ at B point and $3\%$ at B' point.