• The korean journal of orthodontics
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• v.18 no.1 s.25
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• pp.55-63
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• 1988

It has been suggested that the frictional force between bracket and arch wire may impede the tooth movement. The present study was aimed to compare and analyze the effect of wire size, type of ligation, and duration of ligation on the magnitude of frictional force between cobalt chromium wire and stainless steel bracket under the artificial saliva. The results were as follows: 1. Type of ligation and size of wire were the main influencing factor on the level of friction. 2. Stainless steel ligature generated higher frictional forces than elastomeric module. 3. The rectangular wire consistently exhibited more frictional force values than round wires, while there was no significant difference between frictional forces of round wires. 4. In elastic ligature, frictional force decreased with time. 5. Artificial saliva had no significant influence on the frictional force between cobalt chromium wire and bracket.

• The korean journal of orthodontics
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• v.19 no.3
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• pp.147-160
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• 1989

Long face patients are characterized by excessive anterior facial height, lip incompetence at rest, anterior open bite, and gummy smile. A major problem is an inferior rotation of the posterior maxilla and upper molars. Long face patients have been the most difficult for orthodontist to treat successfully. In growing patients, the methods for impeding excessive vertical growth have been used high pull head gear, functional appliance, and combined type of two. One significant improvement comes from using a full arch splint to deliver force to the maxilla more vertically. In adult patients, orthodontic camouflage treatment is biomechanically difficult and doesn't work when the problem is primarilly vertical. Surgical maxillary impaction provides a means for successfully treating most of problems. Also, superior reposition of the chin via a mandibular inferior border osteotomy is effective in decrease of lower anterior facial height and correction of the poor chin-lip balance. Post-surgical stability and the physiologic response are good. The coordinated orthodontic and surgical treatment is necessary for solution the difficult skeletal deformity.

• The korean journal of orthodontics
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• v.41 no.5
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• pp.371-378
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• 2011

Transposition is defined as a dental anomaly manifested by a positional interchange of 2 adjacent teeth within the same quadrant of the dental arch. Maxillary canine-first premolar [Mx4-3] transposition is the most frequent tooth transposition reported in the literature. In this case report, an orthodontic correction of a transposition of the maxillary left canine and first premolar with the help of palatally located mini-implant anchorage is described. Esthetic and occlusal evaluations suggested alignment of the transposed teeth to their correct anatomic positions in the dental arch. The clinical result at the end of the treatment was satisfactory. Alignment was obtained, and intercuspation was adequate. Nevertheless, the maxillary canine showed facial recession, probably because it was initially positioned buccally. Supporting tissue was examined after treatment and no alveolar bone damage was observed.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.2
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• pp.202-206
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• 2010

There are various local and systemic factors which alter the rate of tooth eruption movement. Thyroid hormone has been reported to have proportional relationship with the rate of tooth eruption. The main function of thyroid hormone is the regulation of basal metabolism, but it also affects the rate of tooth eruption. In this report, we will present a case of an 11-year-old girl, who showed sudden increase in orthodontic tooth movement of the impacted canine at certain points, which coincided with the hyperthyroid period. It shows possible relationship between the serum level of thyroid hormone and the rate of orthodontic tooth movement.

• The korean journal of orthodontics
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• v.39 no.5
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• pp.320-329
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• 2009

Objective: The aim of this study was to evaluate the effect of metal primers and thermocycling on shear bond strength between the orthodontic bracket and gold alloy. Methods: For this study, 80 specimens made of dental gold alloy were divided into 8 groups based on the combination of metal primers (none, Alloy primer, Metaltite, V-primer) and thermocycling (with and without thermocycling). Shear bond strength testing was performed with a universal testing machine. Bond failure sites were classified by a modified ARI (Adhesive Remnant Index) score. Results: All metal primer treated groups showed a significantly higher shear bond strength than the only sandblasting treated group without thermocycling (p < 0.05). There were no significant differences on shear bond strength in the groups with thermocycling (p > 0.05). Bond failure sites of the metal primer treated group without thermocycling occurred at gold alloy/adhesive interface, whereas there were no differences on bonding failure sites in the groups with thermocycling. Conclusions: These findings suggest that using metal primer on gold alloy enhances the initial bracket bond strength. But, this effect was not shown with thermocycling.

• The Journal of Korean Academy of Prosthodontics
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• v.57 no.4
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• pp.439-447
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• 2019

The distance between the natural teeth and the implants is an important factor in preserving the periodontal tissues and esthetics. And abnormal positional displacement and tilting of the teeth during restorative procedure may require intentional root canal treatment and may affect masticatory function. This report is to present a successful full mouth rehabilitation of a patient with uneven dentition and collapsed occlusion using orthodontic and implant treatment. The patient had no symptoms or discomfort of temporomandibular joint disorder such as pain or sound. The orthodontic treatment was continued until implant provisional prosthesis delivery. And the vertical height of occlusion was elevated 2mm on anterior basis for anterior teeth protection and esthetics. After the orthodontic treatment, the implant abutments and natural teeth were finally restored with porcelain-fused-to-metal crowns and bridges. Satisfactory function and esthetic outcomes are observed after 6months of follow up.

• The korean journal of orthodontics
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• v.27 no.5 s.64
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• pp.761-770
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• 1997

71 Class I malocclusion samples were selected and they were divided into premolar-extraction and non-extraction groups. Vertical and horizontal cephalometric evaluations on dental and soft tissue measurements were done before and after treatment. Also, treatment results in adolescent patients and adult patients were compared. The following conclusions were obtained: 1. In comparison of extraction and non-extraction groups, all the dental and soft tissue measurements, with exception of SN-MP angle, upper lip to E-line, vertical movement of upper first molar, md horizontal movement of lower first molar, showed statistically significant differences. 2. In comparison of extraction and non-extraction groups of adolescent samples, there were statistically significant differences in upper and lower incisor inclinations, horizontal dental movements from vertical reference line, positional changes in upper and lower lips, and mesial movements of upper first molar. 3. In comparison of extraction and non-extraction groups of adult samples, there were statistically significant differences in upper and lower incisor inclinations, horizontal dental movements from vertical reference line, positional changes in upper and lower lips from I-line and vertical reference line, vertical height of upper first molar, and mesial movement of lower first molar. 4. There was no statistically significant difference in SN-MP angle between extraction and non-extraction groups of both adolescent and adult samples.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.4
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• pp.2150-2159
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• 2014

This study was designed to investigate the status of orthodontic treatment and facial plastic surgery among 389 patients who visited dental clinics located in Seoul and Gyeonggi Province. After the collection of data, an analysis was carried out using a spss statistical program. The analysis results are as follows. the level of satisfaction with orthodontic treatment from patients with experience of the orthodontic treatment turned out to be high(p<0.01). Women considered 3.01 to 4 million won to be reasonable cost for orthodontic treatment (p<0.05), which is higher cost recognized by men, and patients with experience of orthodontic treatment recognized 19 to 24 months as the proper orthodontic treatment period(p<0.01). In addition, women showed higher figures than men in their awareness on the need for orthodontic treatment checkups(p<0.001), and facial plastic surgery experience (p<0.01). With respect to the part of the face on which they hoped to have plastic surgery, eye plastic surgery was higher in women (p<0.01), and nose surgery turned out to be higher in patients with experience of orthodontic treatment(p<0.05). Meanwhile, women considered the eye as the most important part among other facial areas (p<0.001), and they recognized that dentist should perform plastic surgery on both jaws among facial areas(p<0.01). In conclusion, the dental medical staff should provide consultations and operate treatment systems in consideration of gender differences and needs of dental patients. In the case of orthodontic treatment for the improvement of facial appearance, especially double jaw surgery which is closely related to the oral function, professional dental medical staff needs to perform the operation, considering the special oral environment. In addition, it is determined that provision of relevant medical information and promotion of dental service is required to provide patients with correct knowledge about orthodontic treatment and facial plastic surgery.

• The korean journal of orthodontics
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• v.31 no.5 s.88
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• pp.479-487
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• 2001

The perception of facial esthetics is critically important to orthodontists. A viewpoint to facial esthetics is influenced by various factors and dependent on the perception of observer. The purpose of this study was to examine the differences regarding esthetic viewpoints among orthodontists, to identify attractive profiles preferred to orthodontists and to present the characteristic aspects of attractive profiles upon the degree of facial convexity. 35 persons whose faces were judged as attractive one by S orthodontists were selected out of 133 young Korean women. Soft tissue profiles Identified as a good-profile group were measured and analyzed. And then according to the facial convexity, good-profile group was subdivided to convex (G-Sn-Pg$9^{\circ}$) and straight (G-Sn-Pg<$9^{\circ}$) groups for the purpose of this study. There were statistically no significant differences regarding esthetic viewpoints among S orthodontists(p<0.05), even if there exists prevailing concept that the standard for facial esthetics is substantially subjective. N-Pg-Sn and N-Pg-Pn, measured for determining anteroposterior relationship of midfacial convexity, showed significant differences statistically between 2 subgroups (P

• The korean journal of orthodontics
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• v.24 no.1 s.44
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• pp.221-231
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• 1994

The short-term effects of plaque control instruction were studied in 42 adolescent orthodontic patients under active fixed treatment. At first visit, all the patients were received plaque control instruction using materials such as oral hygiene education slides, dentiform, disclosing agents, tooth brush and interdental brush. After that, Pateints were asked to perform the tooth brushing according to instructions. Such a procedure was repeated every week lot 3 weeks. Plaque index and bleeding index were scored once a week for 4 weeks and were compared according to ages, sex and duration with fixed appliance. The results were as follows: 1. Plaque control instruction was effective in reducing plaque accumulation and gingival inflammation of the orthodontic patients. 2. The effect of plaque control instruction was continued during 3 weeks among all groups of subjects, and it was prominent at the first week. 3. There was no statistically significant difference in the effects of the plaque control of instruction according to sex, ages, or duration with fixed appliances.