• The korean journal of orthodontics
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• v.30 no.5 s.82
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• pp.521-533
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• 2000

This study was investigated to evaluate the morphologic characteristics of openbite and deep bite in Class I malocclusion patients and to find skeletodental factors which contributed to vertical discrepancy in Class I malocclusion. The subjects were consisted of 40 control subjects (male 20, female 20) and 40 Class I openbite patients and 40 Class I deep bite patients. Lateral cephalograms in centric occlusion were taken, traced and digitized lot each subjects. The computerized statistical analysis were carried out with SPSS program. The results were as follows. 1. The pattern of vortical discrepancy in Class I malocclusion is mainly influenced by the skeletodental factors under palatal plane. 2. In openbite group, vortical discrepancy is prominent on anterior lower face and is closely related with skeletal factors such as mandibular form and inclination. 3. In deep bite group, dental factors such as ewe of Spee, vertical height of maxillary molar and skeletal factor such as articular angle were contributed to the vertical discrepancy. 4. The multiple regression analysis showed that overbite in Class I molar relationship was determined mainly by dental factors such as lower incisor to occlusal plane angle, curve of Spee, interincisal angle, and ODI.

• The korean journal of orthodontics
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• v.37 no.3 s.122
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• pp.212-219
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• 2007

Objective: The purpose of this study was to provide an anatomical reference for cortical bone and soft tissue thickness, and the attached gingiva width in the mandible. Methods: Fifteen males and fifteen females participated in this study. An acrylic template was fabricated and the radiopaque markers were bonded on the estimated alveolar crest to take measurements of the hard and soft tissue thickness at the same locations. CT images were taken in samples wearing an acrylic template. Cortical bone and soft tissue thickness were measured at 2, 4, 6 and 8 mm from the alveolar crest in interradicular spaces from central incisor to first permanent molar. The attached gingival width was calibrated. Results: Cortical bone thickness was $1.33{\pm}0.38mm$ and soft tissue thickness was $1.49{\pm}0.54mm$. Cortical bone thickness was increased in the posterior area, while it was not the case for the soft tissue thickness. In addition, the total thickness was $2.82{\pm}0.70$. The attached gingival width was wider in the anterior area compared to that in posterior area. Conclusion: These results suggest that the attached gingiva width should be considered upon placement of mini-implants in the mandibular posterior area for orthodontic anchorage.

• The korean journal of orthodontics
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• v.33 no.5 s.100
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• pp.323-337
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• 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
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• v.25 no.1 s.48
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• pp.13-18
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• 1995

Craniofacial asymmetry was analyzed in 39 patients with complete unilateral cleft lip and palate(UCLP). The samples are devided into three groups nine below 9 years, twenty three from 9 years 1 month to 14 years and seven over 14 years group. Seventeen measurements were obtained from the tracing of PA X-ray cephalometric headfilms to evaluate the asymmetric characteristics and changes accdording to aging in UCLP. The obtained results were as follows. 1. Facial asymmetry in UCLP is variable(1.22-3.47 $mm/^{\circ}$) and the length from midsagitta1 reference line to maxillary 1st molar, to upper central incisor and the length of mandibular ramus showed significant asymmetry 2. Nasal septum and anterior nasal spine were deviated In the cleft side and the lower border of nasal cavity was 1ower in cleft side. 3. The deviation of nasal septum was continued significantly till after 14 years old.

• The korean journal of orthodontics
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• v.25 no.1 s.48
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• pp.19-29
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• 1995

This study was performed to compare the size of soft palate, tongue and airway according to the types of the malocclusion and evaluate the correlation between the size of soft palate, tongue, airway and dentofacial skeleton respectively. The sample of this study was 98 malocclusion female patients between the ages 12 and 17 years. The lateral cephalometric radiographs were taken and the distance, angle, ratio and area of the dentofacial skeleton, soft palate, tongue and airway were measured and evaluated statistically. The results obtained were as follows: 1. There was significant difference in SNB, ANB, facial angle, facial convexity, A-B plane angel, Y axis to FH, SN-MP, Wits appraisal, ODI and APDI according to the types of malocclusion. 2. The hyoid bone was more posteriorly positioned in Class II malocclusion group than other two groups and superio-inferior position of the hyoid bone was not different according to the malocclusion types. 3. The nasopharyngeal area of Class II and Class III malocclusion group was smaller than that of Class I malocclusion group, and the pharyngeal area of Class II malocclusion group was smaller than that of Class I and Class III maocclusion group. There was no difference of the area of the soft palate, tongue, oropharynx and hypopharynx according to malocclusion types. 4. The ramal height and mandibular body length(Go-Me) showed positive correlation with the area of tongue, nasopharynx, oropharynx, and pharynx. SNA did not correlated with the area of tongue and airway but SNB showed positive correlation with the area of hypopharynx and pharynx. The anterior, posterior facial height, upper and lower central incisor position to facial plane showed positive correlation with tongue area.

• The Journal of Korean Academy of Prosthodontics
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• v.32 no.2
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• pp.327-353
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• 1994

This study was performed to evaluate the effects of number and alignment of implant fixture and various bar designs on the retention of denture and the stress distribution. Six kinds of photoelastic mandibular models and nine kinds of overdenture specimens were designed. A unilateral vertical load was gradually applied on the right first molar to calculate the maximal dislodgement load of each specimen. A unilateral vertical load of 17 Kgf was applied on the right first molar and a vertical load of 10 Kgf was applied on the interincisal edge region. The stress pattern which developed in each photoelastic model was analyzed by the reflection polariscope. The results obtained were as follows: 1. The maximal dislodgement load reversely increased with the distance from the loading point to the implant fixture, while it linearly increased with that from the most posterior implant fixture to the mesial clip. The maximal dislodgement load also increased with the use of a cantilever bar. 2. Under the posterior vertical load, the stress to the supporting tissue of the denture base increased with the distance from the loading point to the implant future. The stress concentration on the apical area of the implant future reversely increased with the distance from the loading point to the implant future. 3. In the overdentures supported by two implant fixtures under the posterior vertical load. the specimen implanted on lateral incisor areas with a cantilever bar exhibited more favorable stress distribution than that without a cantilever bar. The specimen implanted on the canine areas without a cantilever bar, however, exhibited more favorable stress distribution. 4. In the overdentures supported by three implant fixtures. the specimen implanted ell the midline and canine areas exhibited more favorable stress distribution than that implanted oil the midline and the first premolar areas. 5. In the overdentures supported by four implant fixtures. the specimen implanted with two adjacent implant fixtures exhibited more favorable stress distribution than that implanted at equal distance under the posterior vertical load. 6. Under the anterior vertical load, the overdentures supported by three implant fixtures exhibited stress concentration on the supporting structure of the middle implant future. In overdentures supported by two or four implant futures, no significant difference was noted in stress distribution between the types of bars. These results indicate that the greater the number of implant fixtures, the better the stress distribution is. A favorable stress distribution may be obtained in the overdentures supported by two or three implant fixtures, if the location and the design of the bar are appropriate.

• Journal of the korean academy of Pediatric Dentistry
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• v.43 no.3
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• pp.227-236
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• 2016

Periodontal disease, one of the most common oral diseases, has been widely researched. However, in the face of increasing incidence of adolescent periodontitis, there has been only little concern about the periodontal conditions in adolescents. The purpose of this study was to evaluate the periodontal health and assess the prevalence of the periodontal disease and its causing factors among adolescents. The data was collected from subjects ranging from age 10, 13 and 16 years old in Jeonju by clinical examination and survey. The prevalence of periodontal disease and plaque index value were higher in male than female (p < 0.05). The group of 13 years old subjects had the highest prevalence of periodontal disease (73.3%) and plaque index value (p < 0.05). Among the plaque index of each individual tooth, mandibular central incisor showed the highest value. The survey relating anticipated risk factors demonstrated that the group of 13 years old subjects had the least care for oral hygiene. Also, patients who received the treatment of scaling exhibited high plaque index (p < 0.05), and adolescents with great stress loads showed calculus deposition and increased plaque index (p < 0.05).

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.4
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• pp.652-661
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• 2008

The purpose of this study was to evaluate the skeletal and dental effects obtained by the Frankel functional regulator III in growing children with Class III malocclusions. Cephalometric changes in thirty children at the time of mixed dentition malocclusions (initial mean age, $7.9{\pm}1.1$ years; mean treatment duration, $1.5{\pm}0.8$ years) were analysed. The results were as follows : 1. The skeletal effects on the maxilla showed a significant downward displacement whereas forward displacement was not significant in comparison with the control group. 2. The skeletal effects on the mandible showed statistically significant backward and downward displacement. 3. The dental effects showed statistically significant backward movement in the mandibular incisor tip and increase of overjet The results suggested that forward displacement on the maxilla was insufficient and treatment effects were caused mainly by downward displacement of the maxilla, backward and downward rotation of the mandible, and the increase of overjet during short period.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.4
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• pp.658-665
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• 2007

Oligodontia is defined as the congenital absence of six or more teeth in dentition, excluding the third molars. The prevalence of congenital missing teeth is about 1.6 to 9.6% of population and the prevalence of oligidontia is about 0.08 to 1.1%. The mandibular second premolar is the most frequently absent after the third molar, followed by the maxillary lateral incisor and upper second premolar. Females seem to be affected slightly more than males. Oligodontia may occur either in isolation, or as a part of a syndrome such as ectodermal dysplasia. Different causes are possible for oligodontia: physical obstruction or distruction of the dental lamina, space limitation, functional abnormalities of the dental epithelium, failure of induction of the underlying mesenchyme, chemotherapy, radiotherapy or genetic factor. Because oligodontia would result in esthetic and functional problems, such as facial asymmetry or occlusal disharmony, early diagnosis from clinical and radiographic examination was necessary. And appropriate treatment plan should be followed. This case report was about oral conditions and treatment of the oligodontia patients who have no specific systemic disease.

• The korean journal of orthodontics
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• v.28 no.2 s.67
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• pp.255-268
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• 1998

This study was investigated to assess the difference of facial height and occlusal plane inclination between normal occlusion group and class II malocclusion group. The subjects consisted of 50 normal occlusion (male 25, female 25) and 50 class II(male 25, female 25) malocclusion patients. All subjects are adult. lateral cephalogram was taken with standard method traced, and digitized for each subjects. The computerized statiscal analysis was carried out with SPSS program. The results were as follows 1. In class II malocclusion group, variables significant different from normal occlusion group were as follows ; SN-FOP, FH-BOP, MP-BOP, AB-BOP, AB-FOP, Facial plane-BOP, FP-FOP 2. In class II malocclusion group, the posterior facial height -especially posterior lower facial height-was significantly smaller than normal occlusion group.(P<0.05) 3. In class II malocclusion group, the angles between occlusal plane and upper and lower incisor, the angle between upper molar and bisected occlusal plane were significantly larger than those of normal occlusion group. (P<0.05) 4. L1 to Mandibular plane (mm) was a unique factor of occlusal plane position that showed significant difference in class II malocclusion group. 5. The correlation between overbite and occlusal plane inclination existed in class II malocclusion group, but the correlation didn't exist in normal occlusion group.