• The korean journal of orthodontics
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• v.17 no.2
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• pp.223-248
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• 1987

The early tissue reactions in the periodontal tissues of the tension zones following the application of force (30gm) to the maxillary first molar teeth of the albino rats were studied by the light microscopy and electron microscopy The increase of periodontal fibroblasts was evident, particularly in 1 day survival period. Osteoblast differentiation and new bone formation on the alveolar bone surface were occurred from 1 day survival period. Mononuclear phagocytes occurred consistently and in relatively high number adjacent to and at some distance from blood vessel Extensive breakdown of collagen fibers was observed. The increase of the phagocytosis of collagen by the active fibroblasts was evident Also, collagen fibrils were sparse or lost near the macrophage.

• The korean journal of orthodontics
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• v.18 no.2
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• pp.475-488
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• 1988

Certain malocclusion are associated with specific "facial type," and it is important for the clinician to classify the common facial characteristic of each patient. Because the reaction to treatment mechanics and the stability of the denture is depended upon the analysis of the facial pattern. Basically, there are 3 district facial types or patterns under which almost all malocclusion can be classified. 1. mesofacial is the most average growth. 2. brachyfacial which is a horizontal growth pattern has a week muscle, with dental arch, deep bite. 3. dolichofacial which is a vertical growth pattern has a strong muscle, narrow dental arch, open bite. Brachyfacial pattern show a resistant to mandibular rotation during treatment can accept a more protrusive denture and are prominantly nonextraction, whereas dolichofacial patterns tend to open during treatment require a more retracted denture in order to assure post-treatment stability. Brachyfacial pattern would better treat to use extrusive force system, whereas dolichofacial pattern treat to use intrusive force system with head gear and intermaxillary elastics.

• The korean journal of orthodontics
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• v.24 no.3 s.46
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• pp.587-620
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• 1994

This study was aimed to evaluate the changes in condylar position when severe anterior open bite patients were treated with MEAW. The subjects consisted of 11 patients(21 TMJs) who visited the departement of orthodontics in SNUH, having severe anterior open bite as a chief complain. They were supposed to wear the up and down elastics and MEAW after finishing the leveling. The condylar position was evaluated with individualized corrected tomography in centric occlusion taken before and after treatment. The results were as follows; 1. In the change of condylar position after treatment, there were no statistically significant differences in right and left TMJs. 2. In the change of condylar position after treatment, there were no statistically significant differences in each malocclusion groups. 3. There were no statistically significant differences in percent dispacement of condyle between before and after treatment 4. There were no statistically significant differences in the amount of change in condylar change.

• The korean journal of orthodontics
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• v.24 no.3 s.46
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• pp.621-630
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• 1994

The purpose of this study was to evaluate root resorption and alveolar bone resorption pattern by jiggling movement. 16 adult cats were divided into 4 groups(6, 12, 18, 24 days). In test side, mesio-distal jiggling force was applied in right maxillary 1st premolar in 3 days cycle In control side, mesial force was applied in left maxillary 1st premolar. Radiographic and histologic observation were performed in 6, 12, 18, 24 days after force application. The results were as follow: 1. Alveolar bone resorption was more severe by jiggling force than by unidirectional force. 2. Root resorption pattern was not different between jiggling force and unidirectional force. 3. Combined pattern of bone resorption and new bone formation appeared in jiggling group. 4. New bone formation began to appear at periapical area of jiggling group after 24 days, because alveolar bone resorption was severe and extrusion resulted.

• The korean journal of orthodontics
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• v.29 no.2 s.73
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• pp.137-146
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• 1999

In this article, we introduce a new method of tooth positioner fabrication using modified T.A.R.G. to measure the inclination and angulation of individual teeth. In finishing stage of orthodontic treatment with a fixed appliance, we anticipate that tooth positioner fabricated using the described construction method provides the movement of individual tooth into a desired position; corrected inclination and angulation of teeth, extrusion, intrusion, rotation and so on.

• The korean journal of orthodontics
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• v.7 no.1
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• pp.31-39
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• 1977

The patient, 18-year-old girl, had a class III malocclusion with the lateral compression of the maxilla due to the premature loss of the canines, mild mandibular prognathism, and mouth breathing habit. The treatment plan consisted of 1) rapid maxillary expansion 2) a period of retention 3) extraction of the first mandibular premolars instead of surgical correction 4) completion of orthodontic treatment with multibanded system. The maxilla was separated in the midline by the application of orthopedic forces via a cemented rapid maxillary expansion device. After 18 months, She gained functional overbite-overjet relationship, good interdigitation of buccal segments, and facial harmony due to the retraction of lower anterior teeth.

• The korean journal of orthodontics
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• v.7 no.1
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• pp.23-29
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• 1977

A 23 year-old female with skeleto-dentoalveolar protrusion of maxilla, minor broken contact points between anterior teeth, and missing of lower 1st molars, has been treated with multibanded edgewise technique. After treatment of 14 months, she has gained functional overbite-overjet relationship and facial harmony due to the retraction of upper anterior teeth. Root resorption was slight. Especially, us ing the space of missed lower 1st molars instead of extracting lower premolars, expected and favorable results were obtained.

• The korean journal of orthodontics
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• v.13 no.2
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• pp.209-222
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• 1983

Three patients who had Angle's Class II Division 1 malocclusion were treated by Bioprogressive therapy. In spite of their occlusions, the 3 patients did not have any skeletal problems. Their skeletal patterns were within normal range. So headgear or functional appliance therapy were not considered. During the treatment procedure, the most noteworthy results of Bioprogressive therapy were the effect of the Utility arch to intrude 4 mandibular anterior teeth, the effect of the Cuspid retractor in cuspid retraction and the effect of the Double delta retraction arch in the retraction of 4 anterior teeth. The whole treatment results in these cases which were achieved by Bioprogressive therapy were very favorable and the efficiency of this therapy was very excellent.

• The korean journal of orthodontics
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• v.24 no.1 s.44
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• pp.87-94
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• 1994

The purpose of this study was to evaluate the torque effect of othodontic wires. Ten types of orthodontic wires (five types of materials, two types of cross-sectional dimensions) were selected. Each group of ire type was constituted with five specimens. These specimens were tested on the universal testing machine(Instron) with specially-designed jig. The torque-twist curve of each wire was obtained and the results were analyzed statistically. The results were as follows. 1. 0.017'$\times$ 0.025' wire showed more torque effect than 0.016'$\times$ 0.022' wire at the same twist. 2.Torque effect was the greatest in stainless steel and the least in Nitinol. 3.The maximum amount of torque was the greatest in heat-treated Blue Elgiloy and the least in Nitinol.

• The korean journal of orthodontics
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• v.6 no.1
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• pp.47-54
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• 1976

This study was conducted to investigate the effects of multibanded orthodontic appliances on dental caries activity. The subjects consisted of 50 males and females with multibanded orthodontic appliance and the same number of caries free group. The following conclusions were obtained, 1. There was significant difference between the experimental group and control group in the tests of Snyder colorimetric test, acid :buffering capacity and oral glucose clearance test (at $5\%$ level of significance). 2. There was no significant difference between the experimental group and control group in the tests of unstimulated salivary flow fate, stimulated salivary flow rate and salivary viscosity test (at $5\%$ level of significance). 3. Dental caries activity was higher in experimental group than in control group.