• 대한치과의사협회지
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• 제10권9호
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• pp.585-586
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• 1972

The demonstration of glycoprotein in developing mandibular bone was observed histochemically, using Clara method and Von Kossa method. The glycoprotein reaction showed slight activity in New bilding bone matrix.

• 치과방사선
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• 제22권2호
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• pp.241-252
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• 1992

The purpose of this study was to investigate the changes of morphology and structure of bone tissue in the irradiated mandibular bone in rats which were fed a low calcium diet. In order to carry out this experimant, 64 seven-week old Sprague-Dawley strain rats weighing about 150gms were selected and equally divided into one experimental group of 32 rats and one control group with the remainder. The experimental group and the control group were then subdivided into two groups when the rats reached ten-week old, 16 were assigned rats for each subdivided group, exposed to irradiation. The two irradiation groups received a single dose of 20 Gy in the jaws area only and irradiated with a cobalt-60 teletherapy unit. The rats in the control and experimental groups were serially terminated by fours on the 3rd, the 7th, the 14th, and the 21st day after irradiation. Following termination, both sides of the dead rats mandibular bodies were removed and fixed with 10% neutral formalin. One side of the mandibular body was radiographed with a soft X-ray apparatus. Thereafter, the obtained microradiographs were observed by a light microscope. The remaining side of the mandibular bone was further decalcified and embedded in paraffin as using the general method. The specimen sectioned and stained with hematoxylin and eosin, and Rabit Anti-Human Tumor Necrosis Factor-a, observed by a light microscope. The obtained results were as follows: 1. Microradiogram revealed that thinning of the cortex and a decrease in the trabecula of the interradicular bone and mandibular body were observed and noted from the start to finish throughout the experiment in the non-irradiated rats on the low calcium diet rather than in the non-irradiated rats on the normal diet. In microscopic observations, there were marked osteolytic changes in the center of the bone marrow. 2. Microradiogram revealed that thinning of the cortex and a decrease in the trabecula of interradicular bone and mandibular body were more marked after 7 days in the irradiated rats on the low calcium diet rather than in the non-irradiated rats on the low clacium diet. In microscopic observations, osteoblasts were decreased markedly after 7 days, and a few osteoclasts were observed. 3. Microradiogram revealed that thinning of the cortex and a decrease in trabecula of interradicular bone and the mandibular body were more marked from the strart to finish troughout the experiment in the irradiated rats on the low calcium diet rather than in the irradiated rats on the normal diet. In microscopic observations, there were no osteolytic changes noted in the irradiated rats on the normal diet. 4. In immunocytochemical findings, a few bone marrow cells including Tumor Necrosis Factor were observed in the irradiated rats on the normal diet, but was not observed in the rats on the low calcium diet.

• 한국임상수의학회지
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• 제36권2호
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• pp.106-108
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• 2019

This clinical report describes hemisection and endodontic treatment of first molar tooth and mandible fracture repair in a dog. A 10 years old spayed female shih-tzu was diagnosed as left mandibular fracture by oral examination and dental radiography. First, partial odontectomy of mesial root of mandibular first molar placed in fracture line was performed, and then endodontic treatment of distal root and bone graft in extraction site was performed. Thereafter the fracture region was fixed with interdental wiring and acryl resin splint. Mandibular fracture site was healed without any complications, observed for 19 weeks follow-up period. Upon this result, this case is proving that fractured mandible can be treated successfully with hemisection followed by bone graft, interdental wiring and acryl resin splint to preserve the remaining tooth for mastication rather than tooth extraction.

• Imaging Science in Dentistry
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• 제44권1호
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• pp.43-52
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• 2014

Purpose: This study was designed to evaluate whether magnetic resonance imaging (MRI) is appropriate for detecting early changes in the mandibular bone marrow and pulp tissue of rats after high-dose irradiation. Materials and Methods: The right mandibles of Sprague-Dawley rats were irradiated with 10 Gy (Group 1, n=5) and 20 Gy (Group 2, n=5). Five non-irradiated animals were used as controls. The MR images of rat mandibles were obtained before irradiation and once a week until week 4 after irradiation. From the MR images, the signal intensity (SI) of the mandibular bone marrow and pulp tissue of the incisor was interpreted. The MR images were compared with the histopathologic findings. Results: The SI of the mandibular bone marrow had decreased on T2-weighted MR images. There was little difference between Groups 1 and 2. The SI of the irradiated groups appeared to be lower than that of the control group. The histopathologic findings showed that the trabecular bone in the irradiated group had increased. The SI of the irradiated pulp tissue had decreased on T2-weighted MR images. However, the SI of the MR images in Group 2 was high in the atrophic pulp of the incisor apex at week 2 after irradiation. Conclusion: These patterns seen on MRI in rat bone marrow and pulp tissue were consistent with histopathologic findings. They may be useful to assess radiogenic sclerotic changes in rat mandibular bone marrow.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제42권4호
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• pp.209-214
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• 2016

Traumatic bone cyst (TBC) occurs preferentially on the mandibular symphysis and body, but rarely on the mandibular condyle. When TBC occurs in the condylar area, it can usually be related with or misdiagnosed as a temporomandibular joint disorder. A 15-year-old female patient visited the Temporomandibular Joint Clinic with a 5-year history of pain and noise localized in the left temporomandibular joint. On imaging, a well demarked oval-shaped radiolucent lesion was observed on the left condyle head. The patient underwent cyst enucleation and repositioning of the bony window on the lateral cortex of the affected condyle head under the impression of subchondral cyst or TBC; however, no cystic membrane was found. The bone defect resolved and showed no recurrence on the serial radiographic postoperative follow-up for 43 months after surgery.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제41권
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• pp.51.1-51.8
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• 2019

Purpose: It has been reported before that the amount of pharyngeal airway space (PAS) significantly decreases following mandibular setback (MS) surgery in patients with mandibular prognathism (MP). Further, MP patients with an anterior open-bite (AOB) presentation may show a larger decrease in PAS compared with those without AOB. However, studies on postoperative PAS changes in MP patients with AOB remain rare. This study sought to evaluate changes in PAS and hyoid bone positioning following MS surgery in MP patients with and without AOB. Patients and methods: Twenty patients who underwent two jaw surgery involving MS movement were included. Patients were divided into a non-AOB group (n = 10; overbite > 2 mm) and an AOB group (n = 10; overbite < - 4 mm). Three-dimensional changes in PAS and hyoid bone positioning were compared and statistically evaluated pre- and postoperatively using computed tomography (CT). Results: The mean magnitude of MS was 6.0 ± 2.8 mm and 5.6 ± 3.2 mm in the non-AOB group and AOB group, respectively. The oropharyngeal volume and upper hypopharyngeal volume were significantly reduced after surgery in both the groups (p = 0.006 and p = 0.003), while the retroglossal cross-sectional area was significantly reduced only in the AOB group (p = 0.028). Although the AOB group showed a larger decrease in PAS, the difference was not statistically significant between the groups. The position of the hyoid bone showed significant posterior and inferior displacement only in the AOB group, while the vertical displacement of the hyoid bone showed a statistically significant difference between the two groups. Conclusion: PAS was significantly decreased after MS in both the groups, while only the AOB group presented a statistically significant reduction in the retroglossal cross-sectional area. Vertical displacement of the hyoid bone showed a statistically significant difference between the groups, while the PAS change was not. Surgeons should be aware of potential postoperative airway problems that may arise when performing MS surgeries.

• Imaging Science in Dentistry
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• 제37권3호
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• pp.139-147
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• 2007

Purpose: To assess bone changes of mandibular condyle using cone beam computed tomography (CBCT) in temporomandibular disorder (TMD) patients. Materials and Methods: 314 temporomandibular joints (TMJs) images of 163 TMD patients were examined at the Department of Oral and Maxillofacial Radiology, Chonbuk National University. The images were obtained by PSR9000N (Asahi Roentgen Co., Japan) and reconstructed by using Asahivision software (Asahi Roentgen Co., Japan). The CBCT images were examined three times with four weeks interval by three radiologists. Bone changes of mandibular condyle such as flattening, sclerosis, erosion and osteophyte formation were observed in sagittal, axial, coronal and 3 dimensional images of the mandibular condyle. The statistical analysis was performed using SPSS 12.0. Intra- and interobserver agreement were performed by 3 radiologists without the knowledge of clinical information. Results: Osteophyte (2.9%) was found more frequently on anterior surface of the mandibular condyle. Erosion (31.8%) was found more frequently on anterior and medial surfaces of the mandibular condyle. The intraobserver agreement was good to excellent (k=0.78-0.84), but interobserver agreement was fair (k=0.45). Conclusion: CBCT can provide high qualified images of bone changes of the TMJ with axial, coronal and 3 dimensional images.

• 대한치과교정학회지
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• 제20권2호
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• pp.363-379
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• 1990

The purpose of this study was to evaluate the effects of the mandibular retractive force on the mandibular condyle of growing dog. The experimental animals were six mongrel dogs of two-month old. Their deciduous dentition were completed. Two of them was used as control group, and experimental group was composed of remaining four. Head band and chin cup were made of cotton tape, and hooks are fabricated on the chin cup and had band for closed coil. Mandibular retractive force was 100g/side and chin cap appliance was used for 14 hours/day during night. Experimental group were sacrificed at 2, 4, 6, 8 weeks from beginning of the experiment. Right TMJ was prepared for histologic study and left TMJ was examined grossly for disc, fossa, and condyle. The conclusions are: 1. Two-month old control animal showed active cartilaginous growth on the mandibular condyle, therefore showed thick proliferative and hypertrophic zones. Remodeling process in the condyle head was observed in which there were bone resorption on the anterior surface and bone apposition on the posterior surface. 2. Four-month old control animal showed marked reduction of hypertrophic zone but the condylar bone remodeling was more pronounced. 3. In experimental group, there are marked reduction of hypertrophic zone at 4 weeks from beginning of experiment, and hypertrophic zone disappeared at posterior-superior portion of condyle in 6-week experimental animal. 8 week experimental animal showed slight recovery of hypertrophic zone. 4. In experimental group, bone deposition was increased at anterior surface of condyle, and bone resorption was increased at posterior surface of condyle. 5. In control group, the glenoid fossa and surrounding bone showed mainly bone apposition. But experimental group showed bone resorption at anterior surface of articular eminence and increased bone apposition at posterior surface of postglenoid spine. 6. No marked traumatic change was seen but 4 weeks and 8 weeks experimental animal showed flattening of posterior surperior condylar surface. Bone marrow of condyle showed minute focal bleeding in 2 weeks and 4 weeks experimental animal, and congestion and depression of hematopoietic bone marrow during all experimental period.

• 구강회복응용과학지
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• 제32권3호
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• pp.209-213
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• 2016

Stafne 골낭종은 악하선의 발생 시 생긴 하악골의 결손부로 주로 하악골의 후방부나 하악 우각부에 발생한다. 대부분 하치조 신경관 하방에 발생하며 하악골 전방부에 발생하거나 하악 치아와 연관된 경우는 드물다. 또한 하악골의 천공을 일으키는 경우는 더욱 드물다. 본 증례는 하악골 전방부에 발생하여 하악골 천공을 일으킨 치근단낭과 유사한 병소가 stafne 골낭종으로 진단된 희귀한 증례로, 이와 유사하게 하악골에 발생 가능한 병소의 감별 진단과 함께 보고하고자 한다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제18권4호
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• pp.712-717
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• 1996

The term osteomyelitis literally means inflammation of bone marrow. It is described as an inflammatory condition of bone primarily engaging the medullary cavity extending to the periosteum. Following circulatory collapse and ischemia, the involved portions of the bone become necrotic. Cellulitis and osteomyelitis are the most frequent complications of fractures of the mandible and maxilla, because there is an abscessed tooth in the line of fracture. Since most fractures are compound fractures, infection may develop because of contact with oral secretions or outside air. The treatment of chronic osteomyelitis is still under debate. Some authors rely on antibiotics alone, while others advocate combination with surgery. But when infection occurs, establish proper drainage and administer antibiotics. Author treated a case of infected mandibular fracture with mandibular osteotomy, sequestrectomy, iliac bone graft and hyperbaric oxygen therapy, who had suffered suppurative osteomyelitis and mandibular nonunion following the open reduction of the mandibular fracture.