• The korean journal of orthodontics
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• v.6 no.1
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• pp.33-38
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• 1976

For the purpose of evaluating the response of the periodontal tissue in relation to the experimental tooth movement, orthodontic force was applied to 15 female rats. The animals were investigated histopathologically and histochemically by several staining methods. Findings were as follows: 1. The application of 60gm on the rat's molar caused mesial tipping movement and undermining resorption. 2. One day after the insertion of the appliance, the osteoblast was increased in activity but not in number. 3. The osteoclastic activity was decreased as soon as removing the appliance. 4. With the P.A.S. staining, osteoclasts Stained mildly in the initial stage and stained more intensely in the last stage. Osteoclasts revealed negative reaction in the initial stage and stained mildly in the last stage. 5. Slides stained with toluidine blue revealed no conclusive variations between osteoblasts and osteoclasts.

• The korean journal of orthodontics
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• v.42 no.5
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• pp.270-278
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• 2012

In the correction of dental Class III molar relationship in skeletal Class II patients, uprighting of the mandibular posterior segments without opening the mandible is an important treatment objective. In the case reported herein, a C-tube miniplate fixed to the lower labial symphysis and connected with a nickel-titanium reverse-curved archwire provided effective uprighting of the lower molars, without the need of orthodontic appliances on the mandibular anteriors. Using this approach, an appropriate magnitude of force is exerted on the molars while avoiding any negative effect on the mandibular anteriors.

• The korean journal of orthodontics
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• v.50 no.2
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• pp.145-154
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• 2020

Moving the mandibular posterior teeth into a severely atrophic edentulous space is a challenge. A carefully designed force-and-moment system that results in bodily protraction of the posterior teeth with balanced bone resorption and apposition is needed in such cases. This report describes the treatment of a 19-year-old woman with missing mandibular first molars due to juvenile periodontitis. Miniscrews were used as absolute anchorage during protraction of the mandibular second and third molars. Bodily mesial movement of the mandibular second and third molars was achieved over a distance of 11 to 17 mm after 39 months of orthodontic treatment.

• Imaging Science in Dentistry
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• v.34 no.4
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• pp.191-194
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• 2004

This report is to show healing process of two cases of buccal bifurcation cyst (BBC) developed from the mandibular deciduous second molars. Extracting the involved deciduous teeth led to marsupialization of the cysts and promoted eruption of the associated successors without orthodontic force. The cyst-associated premolars in the two cases erupted faster than the premolars on the contralateral noncyst side. The cysts were completely filled with normal bone. The monitoring radiographs showed bone healing, root formation, and path of eruption of the associated teeth after marsupialization of BBC.

• The Journal of the Korean dental association
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• v.16 no.11 s.114
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• pp.849-856
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• 1978

Relapse following rotational movement of the tooth is a common problem in orthodontic practice. To overcome such relapse, many procedures have been advocated: prolonged retention, permanent retention, over-rotation, rotation of teeth at an early age, surgical procedures such as gingivectomy, redressement force, septotomy, et cetra. A 23-year-old woman presented with Angle's Class I malocclusion and extreme rotation of maxillary central incisors. After 15 months' active therapy, septotomy was performed on maxillary central incisors and Howley retainer was applicated for the purpose of overcoming rotational relapse. During the 1 year post-operative observation, negligible, if any, rotational relapse occurred.

• Restorative Dentistry and Endodontics
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• v.42 no.1
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• pp.65-71
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• 2017

A revascularization procedure was shown to be the best alternative therapy for immature teeth with necrotic pulp and apical infection. A 12 year old female with a history of trauma to her upper central incisor and a sinus tract was referred for endodontic treatment. She was an active orthodontic patient and had undergone regenerative endodontic treatment for the past 2 years. Clinical examination revealed no response to sensibility, percussion, and palpation tests. The preoperative radiograph showed an open apex and apical rarefaction. The case was diagnosed as previously treated tooth with asymptomatic apical periodontitis. Regenerative endodontic retreatment was performed, and the case was followed for 3 years. Clinical, radiographic, and cone-beam computed tomography follow-up examination revealed an asymptomatic tooth, with evidence of periapical healing and root maturation.

• Journal of Korean Dental Science
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• v.14 no.1
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• pp.40-45
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• 2021

During orthodontic treatment of impacted teeth, use of appropriate anchorage against the traction force is important. Tooth anchorage with multi-bracket appliances is commonly used but sometimes it causes unwanted movements of adjacent teeth. Skeletal anchorage devices are therefore considered to minimize such side effects. Still their survival rate and positioning are highly limited according to the bone density and the interradicular space. This case report presents a case of two impacted teeth, one of which is dilacerated and horizontally angulated. Using the microplate with short screws and a bendable neck, negative effects on adjacent teeth were minimized and impacted teeth were repositioned with good stability.

• The korean journal of orthodontics
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• v.20 no.1
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• pp.61-86
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• 1990

To study the effect of prostglandin $E_2$ and evening primrose oil on orthodontic tooth movement in rats, one hundred and sixty rats were divided into four groups of 40 rats each. One group, injected with saline on the palate subperiosteally, served as a control group. A second and third group were injected subperiosteally on the palate with $PGE_2$ $10{\mu}g$ and evening primrose oil 10mg respectively. The fourth group was given indomethacin $20{\mu}g/m{\ell}$ orally by water bottle. The maxillary first molar was moved mesially from the incisors using a 50gm force rubber band. In each group at the 1, 2, 3, 5, and 7th day, 4 rats were examined by light microscope, and 4 by electron microscope. The obtained results were as follows: 1. Osteoclastic activity was maximum at the 3rd day in the $PGE_2$ group on the interradicular alveolar bone of the first molar, followed by the evening primrose oil group, control group, and indomethacin group. 2. Root resorption and vacuolar changes were maximum in the $PGE_2$ group. 3. At the 3rd day of the $PGE_2$ group, the osteoclasts showed well developed ruffled borders and clear zones. At the same day, the evening primrose oil group also showed well developed ruffled borders and clear zones, but less than the $PGE_2$ group. 4. At the 3rd and 5th day of the $PGE_2$ group, fibroblasts showed phagocytized fragmented collagen fibers in the cytoplasm. At the 7th day of the $PGE_2$ group, fibroblasts showed collagen fibers forming at the cell membrane surface.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.3
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• pp.465-470
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• 2003

Transverse and oblique crown-root fractures constitute a major therapeutic problem, particularly in young dentitions. Because crown-root fracture may involve enamel, dentin, pulp, and periodontal tissues, management of the injuries must be modified accordingly. When the fracture line was located under the alveolar crest. there are several methods for crown-root fractured teeth with pulp exposure, such as extruding the root fragment with orthodontic force and restoring it, or intentionally extracting the tooth and replanting it to a position which it can be restored. This case, the fractured tooth is intentionally extracted atraumatically, and replanted by rotating approximately 180 degree into the original socket and fixing with an orthodontic wire. At the 8-month recall examination, the root still showed normal mobility and there was not observed any inflammatory or replacement root resorption in the periapical radiograph.

• The korean journal of orthodontics
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• v.22 no.4 s.39
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• pp.823-836
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• 1992

Guiding a tooth along an arch wire results in a counteracting frictional force among arch wires, bracket and ligature. This frictional forces should be eliminated or minimized when orthodontic teeth movement is being planned. The purpose of this study was to evaluate the changes of width, cross-sectional forms and surface morphologies of stainless steel wire and $Elgiloy^{\circledR}$ wire after electropolising. Experimental variables included in this experiment were arch wire materials, current, electrolyte temperature and polishing time. Wire widths were measured by micrometer and cross-sectional forms and surface morphologies were examined with optical microscope and scanning electron microcope. The results were as follows: 1. The mean and standard deviation of widths of stainless steel wire and $Elgiloy^{\circledR}$ wire varying polishing time with condition of $249A/dm^2$ and $20^{\circ}C,\;249A/dm^2$ and, $332A/dm^2$ and $20^{\circ}C$ and $332A/dm^2$ and $250^{\circ}C$ were obtained. 2. With increasing polishing time, the widths of stainless steel wire and $Elgiloy^{\circledR}$ wire became decreased proportionally 3. The changes of widths of stainless steel wire and $Elgiloy^{\circledR}$ wire were statistically insignificant between $20^{\circ}C$ group and $25^{\circ}C$ group, but significant between $249A/dm^2$ group and $332A/dm^2$ group. 4 The cross-sectional forms of wire after electropolishing were not changed in stainless steel wire, and while it were changed to rounded corners in $Elgiloy^{\circledR}$ wire. 5. The surface morphologies of wire after electropolishing were scratch-absent and more smoothened both in stainless steel wire and $Elgiloy^{\circledR}$ wire.