• 대한치과교정학회지
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• 제6권1호
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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.

• 대한치과의사협회지
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• 제37권2호통권357호
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• pp.126-130
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• 1999

Forty healty patients (15 males and 25 females) between 19 and 45 years of age with mandibular impacted third molar were selected for this tudy. A visual analog scale from 0 to 100 was used on the day of the procedure and on the first postoperative day for patient pain assessment. 1. In comparative study according to anesthesia, preoperative medication, depth of impacted teeth and gender, there were a variable range of pain and no significant differences statistically. 2. Intraoperative pain was the highest in the 2nd decade and first postoperative pain was the highest in the 3rd decade (P=0.0398) 3. Intraoperative and postoperative pain of operative duration below 10 minutes were the lower than that between 11 to 20 minutes (P=0.0398)

• 대한치과교정학회지
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• 제16권1호
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• pp.155-165
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• 1986

Recently, straight-wire appliance is widely used with great concern in clinical orthodontic field. The purpose of this study was to collect the information of the straight-wire appliance and to determine the crown inclination in clinical orthodontics. The author analyzed the study model of 78 individuals with normal occlusion. The obtained results were as follows. 1. Mean, maximum value, minimum value and standard deviation of crown inclination of upper and lower teeth were obtained. 2. The lingual crown inclination of upper tooth had constant value from first premolar through second molar, the lingual crown inclination of lower tooth progressively increased from canine through second molar. 3. As Howes' ratio was decreased, the crown inclination of upper incisors was increased. 4. Narrowing the upper arch, the crown inclination of upper incisors was increased.

• 대한치과의사협회지
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• 제23권7호통권194호
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• pp.625-630
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• 1985

11 years 7 months old female had a reverse object of anterior teeth and class III molar relationship. Maxillary right and left canines were erupted labially and lower left lateral incisor was congenitally missed. She was treated by rapid palatal expansion and full band technique with extraction of maxillary and mandibular second molars. The following results were obtained. 1. Maxilary arch was expanded. 2. Anterior cross-bite and crowding was corrected. 3. Molar relationship was corrected. 4. Profile was somewhat improved.

• 대한치과교정학회지
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• 제24권3호
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• pp.721-733
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• 1994

Orthodontic tooth movement is closely related to the stress on the periodontal tissue. In this research the finite element method was used to observe the stress distribution and to find the best condition for effective tooth movement in the case of unilateral molar expansion. The author constructed the model of lower dental arch of average Korean adult and used $.032'\times.032'\times60mm$ TMA wire. The wire was deflected in the horizontal and vertical direction to give the 16 conditions. The following results were obtained ; 1. When the moment and force were controlled properly the movement of anchor tooth was minimized and the movement of moving tooth was maximized. 2. As the initial horizontal deflection increased the buccal displacement of both teeth was also increased. As the initial horizontal deflection increased the lingual movement of anchor tooth and the buccal movement of moving tooth increased. 3. When the initial horizontal and vertical deflection rate was 1.5 the effective movement of moving tooth was observed with minimal displacement of anchor tooth.

• 대한치과교정학회지
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• 제19권2호
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• pp.37-55
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• 1989

The tissue reactions concerned in alveolar bone remodelling at the pressure zones of rat molar periodontium associated with the application of force (15 gm) to the maxillary first molar teeth of the albino rats were studied by the transmission electron microscopy. Osteoclasts referrable to bone resorption were observed thereafter 3 hour survival period and undermining resorption was generated thenceforth 2 day survival period. Bone resorption, reversal zone and new bone formation were simultaneously observed adjacent to the zone of undermining resorption in the 7 day survival period. Osteoclasts with well developed primary lysosome, ruffled border, clear zone, granules and Golgi apparatus were detected at the zone of the bone resorption, and dark and bright cells adjacent to the osteoclasts as well. Mononuclear cells and perpendicularly arranged collagenous fibers were observed in the reversal zone and, on the other hand, osteoblasts with well developed Golgi apparatus and rough endoplasmic reticulum were detected at the zone of bone formation.

• 치과방사선
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• 제1권1호
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• pp.5-11
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• 1971

The author has observed the orthopantomograms of the maxillary sinus which were taken by special exposure method to study mesiodistal dimension, shape, symmetrical relationship, bony septum of the maxillary sinus and relationship between upper. 1st molar and the maxillary sinus, that were selected 56 cases of 23 to 27 years old male, who have good. systemic conditions and no missing teeth on upper posterior molar in normal occlusion, and obtained following conclusions: 1. Mesiodistal dimensions of the maxillary sinus are shown as follows; The mean of left dimension is 50.94±8.34㎜ and of right dimension is 49.50±9.87㎜. 2. To the shape of the maxillary sinus, V or U shape are 33cases(29.5%) and W shape are 77 cases(70.5%). 3. In the ralationship between upper 1st molar and floor of the maxllary sinus, superimposition are 62 cases (55.36%) and aproach are 50 cases (44.64%). 4. In the right and left symmetrical relationship of the maxillary sinus, symmetry are 37cases (66.07%) and asymmetry are 19 cases (33.93%). 5. The bony septums in the maxillary sinuses revealed that presence of bony septums are 29 cases (25.8%) and absence are 83 cases (74.11%).

• 대한치과교정학회지
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• 제19권1호
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• pp.45-59
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• 1989

This study was undertaken to analyze the displacement and stress distribution in the mandible according to the pulling directions during mandibular first molar cervical traction after mandibular second molar extraction. The 3-dimensional finite element method(FEM) was used for a mathematical model composed of 594 elements and 1019 nodes. An orthodontic force, 450 gm, was applied to the each mandibular first molar in parallel, and below the occlusal plane by $7^{\circ}\;and\;25^{\circ}$ and meet the midsagittal plane by $40^{\circ}$ toward posterior direction. The results were as follows: 1. Mandibular teeth were displaced in more downward, posterior and lateral direction. Especially high stress was noted in case of parallel pull than in case of below the occlusal plane by $7^{\circ}\;and\;25^{\circ}$. 2. Mandibular first molar was moved bodily. 3. Generally, alveolar bone, mandibular body, ascending ramus and mandibular angle portion were displaced in downward, posterior and lateral direction. But coronoid process was displaced in downward, forward and lateral direction, and anterior and inner middle portion of condyle head and neck were displaced in downward, forward and medial direction, and posterior and outer middle portion of condyle head and neck were displaced in upward, forward and medial direction. 4. Maximum stress was observed at the condyle head and neck portion. With steeper direction of force, condyle head and neck showed more stress than parallel relation to the occlusal plane.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제43권1호
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• pp.37-41
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• 2017

Objectives: The aim of this study was to evaluate the implication of third molars in postoperative complications of mandibular angle fracture with open reduction and internal fixation (ORIF). Materials and Methods: Data were collected on patients who presented with mandibular angle fracture at our Department of Oral and Maxillofacial Surgery between January 2011 and December 2015. Of the 63 total patients who underwent ORIF and perioperative intermaxillary fixation (IMF) with an arch bar, 49 patients were identified as having third molars in the fracture line and were followed up with until plate removal. The complications of postoperative infection, postoperative nerve injury, bone healing, and changes in occlusion and temporomandibular joint were evaluated and analyzed using statistical methods. Results: In total, 49 patients had third molars in the fracture line and underwent ORIF surgery and perioperative IMF with an arch bar. The third molar in the fracture line was retained during ORIF in 39 patients. Several patients complained of nerve injury, temporomandibular disorder (TMD), change of occlusion, and postoperative infection around the retained third molar. The third molars were removed during ORIF surgery in 10 patients. Some of these patients complained of nerve injury, but no other complications, such as TMD, change in occlusion, or postoperative infection, were observed. There was no delayed union or nonunion in either of the groups. No statistically significant difference was found between the non-extraction group and the retained teeth group regarding complications after ORIF. Conclusion: If the third molar is partially impacted or completely nonfunctional, likely to be involved in pathologic conditions later in life, or possible to remove with the plate simultaneously, extraction of the third molar in the fracture line should be considered during ORIF surgery of the mandible angle fracture.

• 대한치과교정학회지
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• 제28권4호
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• pp.601-609
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• 1998

한국인에 적합한 preadjusted bracket을 개발하기 위하여 한국인 성인 정상 교합자 14명을 대상으로 crown angulation, inclination, in and out, molar offset angle을 구했다. 정상 교합자 14명의 cast를 3차원 스케닝한 후 스케닝한 모델을 대상으로 컴퓨터 프로그램을 이용하여 측정하였다. 이는 기존의 모델을 직접 수작업으로 측정할 때보다 정확하고 빨리 측정할 수 있었다. 다음과 같은 결론을 얻었다. 1. 한국인 정상교합자의 각 치아의 치축 경사(angulation), 치관 경사도(inclination), in and out, molar offset angle을 구하였다. 2. 3차원 스케너와 컴퓨터를 이용하여 측정하였기 때문에 보다 정확하고, 빠르게 측정할 수 있었다.