• 대한치과교정학회지
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• 제23권4호
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• pp.607-618
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• 1993

If the centric prematurity occurs after orthodontic treatment, it creates centric slide regarded as a possible factor in the cause of temporomandibular disorder and/or postorthodontic relapse. The purpose of this study was to investigate the manner of centric prematurity and centric slide in postorthodantic patients. The 36 orthodontic patients who had been treated with edgewise appliance at least 3 mouths previously were used in this study. After recording centric relation by the leaf gauge technique, the centric prematurity and centric slide were studied using SAM2 articulator and mandibular position indicator. The results were as follows : 1. The highest percentage of centric prematurities were found on the second molars. 2. The buccal incline of the palatal cusp was the most frequent area of centric prematurities in the maxilla, while the lingual incline of the buccal cusp was the most frequent area in the mandible. 3. There were no trends in the direction of centric slide on the mandibular position indicator. 4. There were no significant differences in centric discrepancies between the premolar extraction and nonextraction group.

• 대한치과교정학회지
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• 제23권4호
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• pp.661-669
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• 1993

The purpose of this study was to investigate a possibility of chronic or intermittent bacteremia in patients undergoing orthodontic treatment with fixed orthodontic appliance. Orthodontic patients who had been injured by orthodontic appliances and/or suffered from gingivitis were selected. They had not taken any antibiotics for 1 month. The number of subjects were 21 including 7 males and 14 females. Blood samples of the subjects were cultured and, IgG, IgA and IgM levels in the serum were quantified. The author found following results. 1. No bacterial growth was found in 7-day culture of all the samples. 2. The immunoglobulin levels in serum were confined in normal range. 3. This study could not deny the possibility of transient bacteremia episode undergoing orthodontic treatment.

• 대한치과교정학회지
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• 제1권1호
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• pp.15-20
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• 1970

저자는 흰쥐 27수의 하악제일대구치를 교정용 고무선으로 이동시킨후, 이동의 초기에 나타나는 치수의 반응을 조직학적 방법으로 관찰하는 것을 연구목적으로 하였다. 30 Gm부터 120 Gm까지의 힘을, 12수는 3일간, 15수는 7일간, 각 실험치아에 부여하였다. 관찰결과는 다음과 같았다. 1. 치수조직의 주변화는 치수혈관의 순환장애와 조상아세포의 공포형상으로 나타났다. 2. 적용시킨 힘의 증가에 따라서 상기 조직변화의 범위가 확대되었다. 3. 기외에 치근의 상아질과 백악질의 부분적 흡수도 볼 수 있었다.

• 대한치과교정학회지
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• 제20권2호
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• pp.409-417
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• 1990

Tooth movement would be impeded by frictional force arised between archwire and tube, bracket or elastics in the fixed orthodontic appliances, which could be changed variably by such several factors as the contact area, normal (perpendicular) force and the condition of contact surface. There were many literatures about frictional force in the orthodontic region, but different results were obtained from little controlled research so that was very difficult in clinical application. Therefore we have reviewed comprehensively previous literatures about frictional force and thus several results were obtained as follows: 1. For use species of the orthodontic wire, frictional force was influenced mainly by surface roughness of wire in the absence of binding, while that was influenced mainly by normal force in high binding angulation. 2. For the cross-section and diameter of the wire, the contact area influenced mainly on frictional force in the absence of binding, while wire stiffness influenced mainly on frictional force in high binding angulation. 3. The greater the bracket width, the greater frictional force, and frictional force of the plastic bracket was larger than that of the metal bracket. 4. For ligation type, frictional force of the stainless steel ligation was larger than that of the elastic ligation, and frictional force was directly proportional to ligation force. 5. Variable frictional force were occured from the saliva combined with such another factors as normal force and mode of surface oxide et al.

• 대한치과교정학회지
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• 제20권2호
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• pp.319-331
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• 1990

The purpose of this study was to help examining force system, optimal treatment, and prevention of relapse. Orthodontic force was generated by electromagnets, therefore duration could be freely controlled, and applied for 4 days in dogs. Force magnitude was 200gm and 50gm. duration was contious and intermittent. Intermittent duration was divided into 2 kinds of types in on/off, 1 mininute/1 minute, 10 seconds/1 minute. The results were as follows: 1. In the intermittent group to which force was applied for 10 seconds and ceased for 1 minute, osteoclast was not observed. 2. In the intermittent group to which 200gm of force was applied for 1 minute and ceased for 1 minute, there was blood circulation in periodontal space on pressure side, but mild hyalinized zone was observed. 3. More number of total osteoclast was counted in the pressure side of continous group to which 200gm of force was applied than in any other groups. 4. More number of frontal osteoclast was counted in the pressure side of intermittent group to which 200gm was applied for 1 minute and ceased for 1 minute than in any other groups. 5. On tension side, less periodontal space widening, more new bone and secondary cementum formation were observed in the intermittent group to which force was applied for 1 minute and ceased for 1 minute than in the continous group.

• 대한치과교정학회지
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• 제22권1호
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• pp.135-146
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• 1992

It was the purpose of this study to analyze and compare the mechanical properties of ortho dontic open coil springs. Four variable factors were presented - wire diameter (.008", .009", .010"), lumen size (.030", .032", .036"), arch wire size and shape (.016" round, $ .016^{{\prime}{\prime}}{\times}.022^{{\prime}{\prime}}$ rect.) and alloy type (HiT II, Elgiloy, Sentalloy). The total 104 specimens were divided into 13 groups, and compression test was performed on an Instron test machine. The load deflection curve of each open coil spring was obtained, from which, the load-deflection relations, stiffnesses, percent recoveries were computed statistically. The results were obtained as follows: 1. When the lumen size of the coil spring remained constant, stiffness and percent recovery increased as the wire diameter increased. 2. When the wire diameter of the coil spring remained constant, stiffness and percent recovery decreased as the lumen size increased. 3. The effect of size and shape of arch wire on the coil spring was not statistically significant. 4. In alloy types, stiffness was the greatest in HiT II (55.21), Elgiloy (42.61) and Sentalloy (7.74) in that order. Sentalloy exhibited superior percent recovery and long range of action.

• 대한치과교정학회지
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• 제22권1호
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• pp.17-30
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• 1992

Since 1984, many patients have been treated with Multiloop Edgewise Archwire (MEAW) Technique and diagnosed with ODI (Overbite Depth Indicator) and APDI (Anteroposterior Dysplasia Indicator) by the authors. 234 samples of them were selected randomly for the statistical analysis (age, sex, Angle's classification, treatment period, extraction, ODI etc.). Especially, ODI was analysed statistically and its application methods were reviewed. The results and conclusions were as follows: 1. On the 150 patients with normal overbite, the mean values of Class I, II, III malocclusion were $67.5^{\circ}$, $72.2^{\circ}$ and $59.0^{\circ}$. They were significantly different on the level of p < 0.01. 2. In normal overbite samples, ODI decreased with the increase of APDI and the correlation coefficient was -0.54. It seems that this result reflects the characteristics of AB to mandibular plane angle. 3. The regression equation was Y = - 0.57X + 114.64, where X is APDI and Y is ODI. In cases of small or large APDI, it seems to be absurd that the patient's ODI is compared with the mean ODI to differentiate diagnostically the open bite or deep bite tendency from the normal.

• 대한치과교정학회지
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• 제26권3호
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• pp.241-246
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• 1996

턱은 인간의 성격을 나타내는 요소의 하나로 적절하게 돌출된 턱은 심미적인 안모를 위해 대단히 중요하다. 이부골성형술은 턱의 형태재형성을 목적으로 하며 이를 통해 교정치료 목적의 하나인 안모의 심미성 향상에 기여할 수 있다. 이부골성형술은 수직, 수평적으로 턱의 크기를 확대시키는 축조이부골성형술과 축소시키는 축소이부골성형술로 나눌수 있으며 그활용하는 예는 다음과 같다. 1. 후퇴된 턱의 전진 2. 전방 돌출된 턱의 후퇴 3. 수직고경의 조절 4. 비대칭의 개선

• 한국치위생학회지
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• 제18권5호
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• pp.751-761
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• 2018

Objectives: The purpose of this study was to identify factors affecting choice of treatment hospital (i.e., determinants) and satisfaction with the treatment hospital, and to provide a more satisfactory and high-quality medical service for orthodontic patients. Methods: A questionnaire survey was conducted for approximately 1 month beginning in August 2017, involving patients who visited orthodontic dentistry clinics in Seoul and Gyeonggi-do. Multiple regression analysis was performed on the results to examine factors that affected satisfaction with orthodontic treatment. Results: The determinant of dental clinics was 3.90 points overall; hospital environment and facilities were highest at 4.05, followed by dental hygienist at 3.99, and dentist at 3.97. Factors influencing satisfaction with orthodontic treatment were positively influenced by dentists (p<0.01), medical procedures (p<0.01) and medical expenses (p<0.01). Conclusions: It is important to provide comfort and convenience to patients by simplifying hospital facility management, reception, and reservation procedures.

• 대한치과교정학회지
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• 제12권1호
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• pp.61-68
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• 1982

Tooth Positioner는 band를 제거한 후 가능한 빨리 장착시켜야 susceptible하며 무엇보다도 환자의 생리학적 jaw movement를 설정해서 제작해야 하고 적어도 hingeaxis relation은 찾아서 제작해야한다. Positioner의 장착시간은 하루에 $3\~4$시간의 active biting exercise와 수안시간동안 사용하게 한다. 처음 장착시에 가장 tight하고 이 tightness 는 치아가 요망되는 위치로 근접함에 따라서 점차 감소되고 이 tightness의 감소가 작용효과의 가장 좋은 지침이 되며 자는 하루 하루 그 변화를 느껴야 한다. Positioner가 느슨하게 적합되고 좋은 교합관계를 보이면 장착을 수안시간동안으로 제한시키거나 혹은 깨어 있을 동안 한 두시간 장착하게 한아. 대개 $3\~4$주 후에 predetermined pattern과 유사하게 되며, 일반적으로 장착 후 $8\~10$주 후에 더 장착할 것인가를 결정하고 필요성이 없다면 conventional retainer로 바꾸어 준다. Tooth Positioner는 기능적인 구호흡, thumb sucking, snoring을 해소시켜 줄 수 있으며 jaw relationship이나 overbite문제를 해결할 수 있다. 그리고 chair time을 감소시켜 줄 수 있으며 tissue tone을 자극해서 치아위치를 증진시키는데 끊임없이 작용한다. 그러나 제작에 많은 시간이 걸리고 치아를 배열하는 술자의 능력에 따라 치료효과가 많이 좌우되며 너무 bulky하므로 이물감이 커서 유용하게 장착할 수 있는 시간이 제한적이고 natural muscle balance에 대해 간헐적인 교정력을 가함으로써 치아를 loosening 시킬 수 있다. 이 장치물은 다른 removable appliance와 같이 환자의 협조가 무엇보다 중요하므로 환자에게 장착동기를 유발시켜 주는 것이 좋으며 True Blocked Nasal Airway가 있는 환자에게는 금기증이 된다.