• Journal of Yeungnam Medical Science
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• v.4 no.1
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• pp.151-156
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• 1987

A 25 year and 7 month old man patient who had Angle's classII division 2 malocclusion combined with anterior crowding of upper & lower part was treated by bioprogressive mechanism. After setting our objectives through the use of V.T.O., we programmed a sequence of mechanics. The possible objectives of treatment in the classII division 2 malocclusion can be listed as follows. 1) Relief of crowding & irregularities. 2) Relief of anterior gingival trauma & correction of interincisal inclination. 3) Correction of buccal segment relationship. We'd applied the classII intermaxillary elastics, Quad helix, utility arch wire and sectional arch wire in order to achieve anticipated objectives. As compared with pre & post treatment cephalogram, the result accomplished by this mechanics showed to us that interincisal angle was improved and favorable molar relationship was achieved.

• The korean journal of orthodontics
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• v.25 no.4
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• pp.497-509
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• 1995

With socioeconomic development and change of esthetic recognition, the demand for orthodontic treatment and number of orthodontic patients has been increasing so rapidly. And frequency of malocclusion was changed. So this study was done in an attempt to provide an epidemiologic study so that we can accomodate their orthodontic needs adequately and to obtain the reliable quantitative information regarding the characteristics of orthodontic patients who visited Department of Orthodontics, Seoul National University Hospital from 1985 to 1994. Following results were obtained. 1. The total number of orthodontic patients of SNUDH during 1990-1994 increased in comparing with that of 1985-1989. And it showed that the number of annual patients was increasing trend. 2. The total number of female patients was 1.59 times as high as that of male. It showed that the annual percentage of female patients has been increasing and that of male patients has been decreasing. So demands for orthodontic treatment of malocclusion of female patients were higher than that of male patients. 3. Each total percentage of class I, class II div.1, class II div. 2 and class III was 35.98%, 14.00%, 1.74% and 48.28%. The annual percentage of class I group had been decreasing but it has increased at 1994. However that of Class III group had been increasing until 1991 but it has been decreasing. 4. Each percentage of less than 6 year-old group, D to 8 year-old group, 8 to 12 year-old group, 12 to 18 year-old group and more than 18 year-old group was 2.65%, 8.63%, 32.50%, 27.74% and 28.48%. Annual percentage of 12 to 18 year-old group ( middle & high school students group ) had been decreasing but it has been increasing. However 18 year-old group had been increasing but it has been decreasing. So entrance examination for college and university is an important factor to distribution of age group.

• The korean journal of orthodontics
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• v.13 no.2
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• pp.193-199
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• 1983

The purpose of orthodontic treatment is to produce functional occlusion and to create or maintain facial esthetic harmony. The soft-tissue covering of the face also plays an important role in facial esthetics, speech and other physiologic functions. The study of the soft-tissue profile is important for the planning of orthodontic treatment. The author studied cephalometric X-ray films on 49 patients (23boys, 26 girls) with Angle's class II division 1 malocclusion, ranged from 9 to 13 years of age. Roentgenocephalmetric X-ray films were taken pre and post orthodontic care. Tracings were made in usual manner. The obtained results were as follow. 1. There was no significant sexual difference on mean changes. 2. In the comparison of the soft-tissue thickness changes, Ls-Ls' and Si-Si' in male subjects were remarkable. 9. There were significant correlations between osseous (Ss') change and soft-tissue (Ss) chang, of maxilla in male and female subjects subsequent to orthodontic treatment. 4. The ratios between the protraction of the Ss' and that of the Ss were 1:1.5 in all sexes, the ratios between the Si' and that of the Si were 1:1.4 in male and 1:1.2 in female. 5. There were significant correlations between maxillary central incise. angulation change $({\angle}A)$ and upper lip inclination change $({\angle}B)$ in all sexes. 6. There were little correlations between change in distance difference of Is and Ii and change in distance difference of Ls and Li in all sexes in all sexes.

• The korean journal of orthodontics
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• v.19 no.3
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• pp.67-78
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• 1989

This study was designed to investigate the difference of teeth and craniofacial complex between normal occlusion and Angle's Class II, div. 1 malocclusion in Korean children. The sample was divided into 2 groups, the 66 subjects with normal occlusion and 96 subjects with Angle's Class II, div. 1 malocclusion in both sexes. The results obtained were as follows: 1. No significant differences were observed in ant. cranial base length & cranial flexure (saddle) angle) between normal occlusion & Angle's Class II, div. 1 malocclusion group, but posterior cranial base length of Class II, div. 1 malocclusion group was larger than that of normal occlusion group. 2. No significant difference was observed in the anteroposterior position of Maxilla to cranial base between two groups, but mandibular position in Class II, Div. 1 malocclusion was posterior and interior to that of normal occlusion. 3. The length of maxilla (ANS-PSN) was larger in Class II, div. 1 malocclusion than normal occlusion. The length of mandibular body (Go-Me) was nor different between Class II, div. 1 malocclusion and normal occlusion. 4. Maxillary incisor position of Class II, div. 1 malocclusion to cranial base was more protrusive than that of normal occlusion, but there was no difference in mandibular incisor position between two groups.

• The korean journal of orthodontics
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• v.27 no.3 s.62
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• pp.431-444
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• 1997

This research was carried out to compares the treatment effects of Horizontal and Vertical type activators in Angle's Class II div. 1 maloccusion patients with mandibular retrusion dand to find out whether different treatment effects or growth pattern were observed between sexes in each study groups. The results were as follows: 1. In Horizontal activator group, forward positioning of mandible and vertical increase in anteror face as examplified by increase of LAFH and AEM were observed when pre and post-treatment datas were evaluated. 2. Males samples in Horizontal activator group showed increase in mandiular length accmpanied by posterior positioning of maxilla, wheras female samples in Horizontal activator group showed increase in mandibular body length, labial inclination of mandibular incisors and increase in lower anterior facial height .3. In vertical activator group, increase in AFH, LAFH, PFH and LPFH were observed when pre and post treatment datas were evaluated. 4. Male samples in Vertical activator group showed increase in mandibular body length and anterior and posterior facial heights, whereas females samples of Vertical activator group showed mainly increase in anterior facial height. 5. When pre and post treatment datas of Horizontal and Vertical activator groups were compared, skeletal difference were mainly observed in pretreatment datas but dental difference were observed in post treatment datas ,indicating that two actiators differ only in their effects to dental variables. 6. Difference between sexes were noted after treatment although no difference were observed between sexs in each groups before treatmentt. This indicates that inherent growth effects in each sex exerts more influence 1km appliances used for treatment.

• The korean journal of orthodontics
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• v.19 no.3
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• pp.137-145
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• 1989

The aim of this investigation was to study the effect of orthodontic force on the flow of gingival crevicular fluid and activities of arylsulfatase and brta-glucuronidase in crevicular fluid. The material consisted of 12 persons between the ages of 13 years and 22 years and all were categorized Class I, 4-4 extraction cases Crevicular fluids were sampled from distal crevis of each canine before treatment (phase 1), after bracketing (phase 2), after application of force (phase 3) and after run out of orthodontic force (phase 4). Crevicular fluid flow did not show any significant changes during the period of treatment. The activities of arylsulfatase increased significantly after setting of orthodontic appliance without application of force, but did not show any significant difference after application of force. The activities of beta-glucuronidase increased significantly after application of orthodontic force and decreased with force deminished. These indicated that beta-glucuronidase was good indicator of bone remodelling resulted from initial orthodontic force.

• 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.