• 대한치과교정학회지
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• 제10권1호
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• pp.29-36
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• 1980

Inclined plane, one of frequently used orthodontic appliances, may cause posterior displacement of mandible and injure the normal growth of temporomandibular joint. So author carried out the mandibular posterior displacement experimentally induced by inserting inclined plane in the rat incisors in order to investigate the histological reactions occuring in the temporomandibular joint of experimental animals. Following results were obtained. 1. The posterior displacement of condyle resulted in the widening of anterior synovial space with anterior condylar hyperplasia and posterior condylar atrophy. In addition, tissue changes were more severe in young rats than in adult rats. 2. The tissue reactions were localized only to condylar head ana there were no evidence of traumatic features in young rats. In adult rats, hemorrhage was an additional finding 1 week after experiment. 3. The remodelling processes were accompanied by the increasing or reduction of fibrous layer and subsequent replacement by cartilage layer occured massively and abruptly in young rats, it occured slightly and slowly in adult rats. 4. The remodelling process of injured condyle occured from 1 week to 4 weeks after experiment and completed between 8 weeks after experiment.

• 대한구순구개열학회지
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• 제6권2호
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• pp.131-135
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• 2003

Severe maxilla1y deficiency can be caused by cleft lip and palate(CLP), other craniofacial deformities, atrophy in the edentulous maxilla, and trauma. Patients with maxillary deficiency present a difficult treatment challenge. Traditionally, this skeletal deformity has been treated by Le Fort osteotomy, skeletal repositioning, and fixation with mini-plates and screws. The drawbacks of this method include a limited amount of anterior maxillary advancement often requiring simultaneous mandibular setback, the inability to create new bone, and minimal soft tissue adaptation to the new position, all of which increase the potential of relapse in case of large advancement. The alternative method of maxillary distraction osteogenesis offers promising results for successfully treatment of these patients while potentially minimizing the risk of relapse.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제23권3호
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• pp.226-231
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• 2001

Modified surgical technique for transposition of the inferior alveolar nerve followed by immediate placement of endosseous implants in mandibles with moderate to severe atrophy are presented. Five transpositions of the inferior alveolar nerve together with the installation of 10 implants were performed in four patients. The mean postoperative follow-up time was 17 months, with a range of 8 to 20 months. All implants with functioning pontics remained stable, with no mobility or symptoms of pain and infection during the follow-up period. Neurosensory evaluation was performed using the two-point discrimination test. Two patients had objective neurosensory dysfunction at postoperative, but all the nerve function were reported as normal by the patients 4 months postoperatively.

• Archives of Reconstructive Microsurgery
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• 제9권1호
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• pp.44-48
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• 2000

The advent of free bone flaps has made successful replacement of extensive areas of bone loss in the upper and lower extremities. The microvascular free bone flaps have faster healing without bony absorption or atrophy and can heal in the hostile environment of scarred bed or infection. Since the fibula free flap introduced by Taylor and colleague in 1975, it has been used extensively for skeletal reconstruction of extremities. In 1988, the folded vascularized fibula free flap was first described as a technique to reconstruct significant long bone defect of upper and lower extremities. During the same time, the fibular free flap has evolved to become most preferred choice of mandibular reconstruction. Up to present day, few reports have been made on the fibular free flap used for reconstruction of injured hand containing metacarpal bone and soft tissue defect. We present here our new and unique experiences with vascularized fibular osteocutaneous free flap as useful and satisfactory one for reconstruction of hand with composite defects.

• 한국수의병리학회지
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• 제1권2호
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• pp.125-134
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• 1997

Porcine Reproductive and Respiratory Syndrome Virus infection (PRRSV) was confirmed by serology histopathology immunohistochemistry and bacteriologic examination in young pigs. Four suckling and six weaned piglets submitted from three different farms showed coughing sneezing labored rapid abdominal respiration lethargy and anorexia. Grossly apical and cardiac lung lobes appeared mottled with pale to dark tan discoloration. Submandibular and bronchial lymph nodes were tan and enlarged. All piglets were seropositive for PRRSV antibodies by the indirect immunofluorescent antibody(IFA) test. Microscopically lung lesions were characterized by hyperplasia and hypertrophy of type 2 pneumocytes infiltration of mononuclear cells in alveolar intersitium accumulation of necrotic debris in alveolar spaces accompanied by proliferation of alveolar multinucleated syncytial cells. Using immunohistochemical technique PRRSV antigens were demonstrated in alveolar macrophages and type 2 pneumocytes in histologic lung tissue sections. Also PRRSV antigens were detected in brain lymph nodes spleen and heart. Additionally piglets showed nonsuppurative meningoencephalitis mandibular necrotic lymphadenopathy splenic atrophy and myocardial necrosis.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제29권2호
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• pp.123-131
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• 2007

Introduction: Distraction osteogenesis is widely used as for bone lengthening in patients with maxillofacial deformity and alveolar bone atrophy. One of the major problems in distraction osteogenesis is long consolidation period for 2-3 months, in which the devices have to be fixed on the bone to prevent relapse. It results in scar formation on the face, disturbance of mastication and speech. This study was performed to evaluate the stimulating effect of pulsed electromagnetic field on the early bone consolidation in distraction osteogenesis. Materials and methods: Total 10 rabbit were used (5 for control group, 5 for experimental group). A vertical osteotomy in the mandibular body was performed and the distraction device was fixed. After 5 days distraction was done 1mm per a day for 7 days. A pulsed electromagnetic field (38 Gauss, 60 Hz) was applied for 8 hours per day and it continued for 5 days immediately after distraction in the experimental group. Both groups were sacrificed after 2 weeks. Histological specimens with H&E and Masson Trichrome staining were made and histomorphometrically analysed with image analyser. Results: The device for distraction osteogenesis was displaced in one animal for each group, therefore, only four animals in both groups were evaluated. In both groups, a new bone formation was observed in the distracted area after 2 weeks. The bone formation was enhanced in the experimental groups ($31.76{\pm}8.68%$) compared with control group ($9.94{\pm}3.23%$), its difference was statistically significant (p<0.001). Conclusion: This study suggests that electrical stimulation with electromagnectic field may be effective in the early bone formation after distraction osteogenesis. Further studies with large number of animals are needed before clinical application.

• 구강회복응용과학지
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• 제36권4호
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• pp.272-281
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• 2020

영구치가 선천 결손된 아동에서 유치가 발거되면, 교정적으로 공간을 폐쇄하거나, 성장이 끝나고 임플란트 수복을 시행할 때까지 공간을 유지하게 된다. 그러나 점차 치조골은 위축되고, 향후 보철 수복을 어렵게 하거나 비심미적인 결과를 야기할 수 있으므로, 임상의는 결손 공간과 치조골의 유지 모두 고려해야 한다. 본 증례에는 2개의 하악 전치가 결손된 환아에서 교정용 골성 고정원을 이용한 임시 보철 수복을 시행한 증례이다. 2개의 골성 고정원을 치조정 2 - 3 mm 하방에 수평으로 식립하였으며, 강선이 삽입된 인공치로 고정하였다. 2년의 경과 관찰동안 치은 염증이나 골성 고정원의 탈락은 발생하지 않았다. 또한 방사선 평가에서 인접 치조골의 성장이 저해되지 않았으며, 치조골 폭경 역시 양호하게 유지되었다.