• 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.22 no.4 s.39
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• pp.815-822
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• 1992

Orthodontists want why the patients want orthodontic treatment. Demand and need for orthodontics is very important factors of cooperation and management. Chief complaint would be different according to the race and culture. Our results show that in the control group, Korean female adolescents[chief complaint is cowding$(30.6\%)$, spacing$(26.5\%)$, upper anterior protrusion$(18.4\%)$, anterior cross bite$(8.2\%)$ in order. Korean female adolescents considered anterior cross bite is more nonacceptable than spaeing and anterior protrusion. The purpose of orthodontics seemed to enhance esthetic, dental health, and to improve oral function.

• The korean journal of orthodontics
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• v.24 no.1 s.44
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• pp.193-198
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• 1994

In this study, in order to survey the effect on public recognition in malocclusion and orthodontic treatment by brochures made by Korean orthodontic association, sample were divided into control and experimental group and a questionnaire was inguired and the results were as follows: 1. In the experimental group, frequency of recognition for the need of orthodontic treatment was high, and this indicates dental health behavior and recognition can be inspired by adequate giving of information. 2. Between the control and the experimental group, patterns of the negative opinion was different, and especially the demand for specific orthodontic treatment can be influenced by the content of brochures. 3. The brochures used in this study can call attention to develope the orthodontic aspect for the malocclusion, hereafter more systemic and active measures for development of public dental behavior and recognition should be needed.

• 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.

• The korean journal of orthodontics
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• v.6 no.1
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• pp.71-77
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• 1976

19 years old female had untreated Veau classification class II cleft palate with ectopic eruption of upper right lateral incisor and congenital missing of lower lateral incisors. Upper left lateral incisor, left first molar aid lower left first molar were root restswithperiapicalpathologiclesions. So all root rests were extracted and prosthodontic rehabilitation after orthodontic treatment was planned. She was treated by means of multibanded system with face bow. After 23 months all orthodontic correction were achieved and, as soos as debanding procedure was done she was referred to oral surgeon and prosthodontist for surgical operation and bridge construction.

• The korean journal of orthodontics
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• v.14 no.2
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• pp.241-248
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• 1984

The mechanical properties of Cr-Ni alloy of austenitic stainless steel and Co-Cr alloy orthodontic wires were studied in tension. The wires (0.018 inch) were tested in the as-manufactured and heat-treated conditions. Instron type tension testing machine was used for this study. Mean values and standard deviations were computed. The results were as follows; 1. The Cr-Ni orthodontic wires of austenitic stainless steel are generally superior than the Co-Cr orthodontic wires in ultimate tensile strength, In the elongation, however, Co-Cr orthodontic wire are superior than Cr-Ni orthodontic wires. 2. Increase in the degree of strength by heat treatment are more clearly shown in Co-Cr orthodontic wires than Cr-Ni orthodontic wires. And the elongation is decreased by heat treatment in both case. 3. The changes of the degree of strength by cooling method we not clearly shown, but in Cr-Ni orthodontic wires, air cooling are more effective, in Co-Cr orthodontic wires, cooling effect are scarcely shown.

• The korean journal of orthodontics
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• v.11 no.2
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• pp.65-70
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• 1981

In the present study orthodontic force was applied to the molars of control group and experimental group treated with the lathyrogen beta-aminopropionitrile (BAPN). Observation resulted in the following conclusions : 1) New alveolar bone formation in response to orthodontic force in BAPN-treated rats exceeded corresponding bone formation in control of cup when measured at two tension sites in the periodontal ligament. 2) BAPN administration produced disorganization of the collagenous fibers of the periodontium of experimental group. Multiple eosinophilic cell-free areas were found distributed throughout the radicular portions of affected periodontal ligaments. 3) The areas of periodontium surrounding orthodontically treated teeth exhibited relatively normal organization under these conditions, while the periodontium of adjacent nonorthodontically treated teeth was disorganized. 4) The present results suggest that the typical histologic response to orthodontic force application can occur in the presence of a chemically and physically altered periodontium.

• The korean journal of orthodontics
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• v.19 no.2
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• pp.109-120
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• 1989

We tend to consider only static occlusion such as molar relationship, canine key, and interdigitation at finishing stage. Of course, this static occlusion is important for post-orthodontic stability. But we should remember that mandible is always on the move during its various functions. If no pressure or too much pressure is put on during its functions, untoward tooth movement could occur. And tooth mobility, periodontitis, wear facet, bruxism, and far worse temporomandibular disorder could occur. After many studies have been done on what is a desirable occlusal scheme to strengthen post-orthodontic stability, today, "mutually protective occlusion" is recommended. If an orthodontist does not have understanding about this occlusal scheme during orthodontic treatment, the following conditions will be resulted after orthodontic treatment. I. Centric discrepancy 1. centric prematurity 2. sunday bite 3. molar fulcrum II. Eccentric discrepancy 1. posterior interference 2. anterior interference If we have deep understanding about these discrepancies that can happen after orthodontic treatment and their causes, corrections, and especially preventions against them, post-orthodontic stability could be strengthened and further temporomandibular disorder could be prevented.

• The korean journal of orthodontics
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• v.19 no.2
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• pp.121-129
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• 1989

Pain and pain management have long been items of central concern in dentistry. Although they are given little attention in orthodontics, virtually every patient wearing orthodontic appliances experiences and complains of some extent of pain, and someones have suffered from severe throbbing pain. A form of stimulation-produced analgesia, Transcutaneous Electrical Nerve Stimulation (TENS) is a non-invasive, non-pharmacologic pain control techniques. The clinical application of TENS to orthodontic patients may lead to better patient compliance. And I want to discuss some basic knowledge of this TENS.

• The korean journal of orthodontics
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• v.16 no.1
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• pp.35-49
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• 1986

Etiologies and traditional treatment modalities regarding anterior open-bite were discussed to elucidate the advantages and disadvantages. And an emphasis was placed on the understanding of the true nature of anterior open-bite. Most anterior open-bite malocclusions can be treated with a high degree of sucess and stability without surgical intervention with the congnizance of the anatomy, the physiology and the dynamics of orthodontic mechanotherapy. In this regard, a Multiloop Edgewise Arch Wire (MEAW) Technic, which has been developed during the past twenty years by Dr. Kim, was introduced. Three cases with anterior open-bite malocclusion were presented to demonstrate the mechanotherapy.