• The Journal of Advanced Prosthodontics
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• 제7권6호
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• pp.484-495
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• 2015

PURPOSE. This study was to evaluate the effects of bacterial cellulose (BC) membranes as a barrier membrane on guided bone regeneration (GBR) in comparison with those of the resorbable collagen membranes. MATERIALS AND METHODS. BC membranes were fabricated using biomimetic technology. Surface properties were analyzed, Mechanical properties were measured, in vitro cell proliferation test were performed with NIH3T3 cells and in vivo study were performed with rat calvarial defect and histomorphometric analysis was done. The Mann-Whitney U test and the Wilcoxon signed rank test was used (${\alpha}<.05$). RESULTS. BC membrane showed significantly higher mechanical properties such as wet tensile strength than collagen membrane and represented a three-dimensional multilayered structure cross-linked by nano-fibers with 60 % porosity. In vitro study, cell adhesion and proliferation were observed on BC membrane. However, morphology of the cells was found to be less differentiated, and the cell proliferation rate was lower than those of the cells on collagen membrane. In vivo study, the grafted BC membrane did not induce inflammatory response, and maintained adequate space for bone regeneration. An amount of new bone formation in defect region loaded with BC membrane was significantly similar to that of collagen membrane application. CONCLUSION. BC membrane has potential to be used as a barrier membrane, and efficacy of the membrane on GBR is comparable to that of collagen membrane.

• 대한소아치과학회지
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• 제36권4호
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• pp.607-612
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• 2009

소아기의 악성 종양은 질병으로 인한 소아 사망의 가장 흔한 원인이다. 이에 대한 대표적인 치료 방법으로 항암 화학 요법과 방사선 요법의 단독 사용 혹은 이들의 병용을 들 수 있다. 그러나 이러한 치료 방법은 다양한 구강 내 합병증을 동반한다. 성인과 달리 소아 환자는 항암치료 시기에 일부 영구치가 활발한 발육단계에 있으므로 발육중인 치아에 치과적 합병증이 예상된다. 치과적 합병증의 정도는 화학약물의 종류, 용량 및 방사선 조사 빈도와 치료 당시 환자의 나이에 따라 달라진다. 본 증례들에서는 특정 영구치의 발육단계에 있는 만 1-4세경에 종양의 치료를 위해 항암 화학 요법과 방사선 치료를 받은 어린이 3명을 대상으로 치료 내용과 치아 발육 상황을 검토해 보았다. 이환된 치아의 수나 그 정도에 차이는 있으나, 각각의 환자에서 영구치 치배의 선천 결손, 왜소치, 치근 저형성 등 발육장애 관련 소견이 관찰되었다. 항암치료를 받은 병력이 있는 소아에 있어서 항암치료 이후에 나타날 수 있는 일반적인 구강 합병증 이외에 발육시기 동안 치아에 미치는 영향을 고려하여, 공간 문제를 포함하여 향후 발생 할 수 있는 다앙한 문제점 예방을 위한 장기적인 관찰과 관리가 필요할 것으로 생각된다.

• Imaging Science in Dentistry
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• 제35권4호
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• pp.203-205
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• 2005

Purpose: This study was aimed to compare skin entrance dose of digital radiography with that of film radiography and to show the dose reduction achievement with digital systems at 11 dental schools in Korea. Materials and Methods: Forty six intraoral radiographic systems in 11 dental schools were included in this study. Digital sensors were used in 33 systems and film was used in 13 systems. Researchers and the volunteer visited 11 dental schools in Korea. Researchers asked the radiologic technician (s) at each school to set the exposure parameters and aiming the x-ray tube for the periapical view of the mandibular molar of the volunteer. The skin entrance doses were measured at the same exposure parameters and distance by the technician for each system with a dosimeter (Multi-O-Meter : Unfors instruments, Billdal, Sweden). Results: The median dose was $491.2{\mu}Gy$ for digital radiography and $1,205.0{\mu}Gy$ for film radiography. The skin entrance dose in digital radiography was significantly lower than that of film radiography (p<0.05). Conclusion: Fifty-nine percent skin entrance dose reduction with digital periapical radiography was achieved over the film radiography in Korean dental schools.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제41권6호
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• pp.332-337
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• 2015

Dental infections and maxillary sinusitis are the main causes of osteomyelitis. Osteomyelitis can occur in all age groups, and is more frequently found in the lower jaw than in the upper jaw. Systemic conditions that can alter the patient's resistance to infection including diabetes mellitus, anemia, and autoimmune disorders are predisposing factors for osteomyelitis. We report a case of uncommon broad maxillary osteonecrosis precipitated by uncontrolled type 2 diabetes mellitus and chronic maxillary sinusitis in a female patient in her seventies with no history of bisphosphonate or radiation treatment.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제16권3호
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• pp.303-308
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• 1994

The ameloblastoma is considered to be a slowly growing locally invasive tumor with a high rate of recurrence if not removed adequately. Ameloblastoma generally dose not metastasize to distant places. In very rar case, ameloblastoma changed its histologic appearance to carcinoma or showed distant metastasie, these generally called malignant ameloblastoma. Inadequate surgical procedures, radiation therapy, and a long duration of this tumor seem to have significant relation to the development of metastasis. Therefore, adequate surgical treatment of the primary lesion plays an important role in the prevention of metastasis postoperatively. This report described an instance of malignant ameloblastoma and review of literature.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제27권6호
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• pp.543-546
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• 2001

Primary intraosseous carcinoma(PIOC) is defined as a squamous cell carcinoma arising within the jaw, having no initial connection with the oral mucosa. The squamous cell carcinoma within the bone can be presumably developed from residues of the odontogenic epithelium, therefore, it is seen in the jaw only. Metastatic carcinoma from another primary site should be excluded in the diagnosis of Primary Intraosseous Carcinoma. This is a case of 62-year-old man, who initially diagnosed as odontogenic cyst on maxilla, but its pathologic examination was diagnosed as squamous cell carcinoma with odontogenic cyst. We treated this patient with partial maxillectomy, modified radical neck dissection(mRND), and postoperative radiation therapy.

• Imaging Science in Dentistry
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• 제30권4호
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• pp.287-292
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• 2000

A case of dento-maxillofacial abnormality involving a 10-year-old male patient with a history of esthesioneuro-blastoma is presented. This patient had been treated with 54 Gy /sup 60/Co-gamma-radiation to the nasal cavity for 6 weeks and 6 cycles of combination chemotherapy of Cyclophosphamide, Cisplatin, Adriamycin, VM-26 (Tenipo-side), and DTIC (Dacarbazine) when he was 16 months of age. Five years after cessation of cancer therapy, he was disease free and transferred for extensive dental care to Kyung Hee University Dental Hospital. A clinical and radiologic follow-up over last 4 years showed root stunting, premature closure of the root apices, microdontia, developmental arrest, small crowns, and partial anodontia. Maxillofacial morphology evaluated by cephalometric analysis showed deficiency of maxillary development.

• Imaging Science in Dentistry
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• 제49권3호
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• pp.179-190
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• 2019

Panoramic radiographs and computed tomography (CT) play a paramount role in the accurate diagnosis, treatment planning, and prognostic evaluation of various complex dental pathologies. The advent of cone-beam computed tomography (CBCT) has revolutionized the practice of dentistry, and this technique is now considered the gold standard for imaging the oral and maxillofacial area due to its numerous advantages, including reductions in exposure time, radiation dose, and cost in comparison to other imaging modalities. This review highlights the broad use of CBCT in the dentomaxillofacial region, and also focuses on future software advancements that can further optimize CBCT imaging.

• Imaging Science in Dentistry
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• 제49권3호
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• pp.219-228
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• 2019

Purpose: The aim of this study was to determine the reasons and solutions for intraoral phosphor storage plate (PSP) image artifacts and errors, and to develop an appropriate classification of the artifacts. Materials and Methods: This study involved the retrospective examination of 5,000 intraoral images that had been obtained using a phosphor plate system. Image artifacts were examined on the radiographs and classified according to possible causative factors. Results: Artifacts were observed in 1,822 of the 5,000 images. After examination of the images, the errors were divided into 6 groups based on their causes, as follows: images with operator errors, superposition of undesirable structures, ambient light errors, plate artifacts (physical deformations and contamination), scanner artifacts, and software artifacts. The groups were then re-examined and divided into 45 subheadings. Conclusion: Identification of image artifacts can help to improve the quality of the radiographic image and control the radiation dose. Knowledge of the basic physics and technology of PSP systems could aid to reduce the need for repeated radiography.

• Imaging Science in Dentistry
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• 제30권3호
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• pp.183-188
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• 2000

Purpose: This study was to evaluate the beam quality of intraoral X-ray equipments used at Yonsei University Dental Hospital (YUDH) using the half value layer (HVL) and the characteristic curve of intraoral standard X-ray film. Materials and Methods : The study was done using the intraoral X -ray equipments used at each clinical department at YUDH. Aluminum filter was used to determine the HVL. Intraoral standard film was used to get the characteristic curve of each intraoral X-ray equipment. Results: Most of the HVLs of intraoral X-ray equipments were higher than the least recommended thickness, but the REX 601 model used at the operative dentistry department and the X-707 model used at the pediatric dentistry department had HVLs lower than the recommended thickness. The slopes of the characteristic curves of films taken using the PANP AS 601 model and REX 601 model at operative dentistry department, the X-70S model of prosthodontic dentistry department, and the REX 601 model at the student clinic were relatively low. Conclusion: HVL and the characteristic curve of X-ray film can be used to evaluate the beam quality of intraoral X-ray equipment. In order to get the best X-ray films with the least radiation exposure to patients and best diagnostic information in clinical dentistry, X -ray equipment should be managed in the planned and organized fashion.