• 대한치과의사협회지
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• 제39권5호통권384호
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• pp.419-422
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• 2001

• 대한방사선기술학회지:방사선기술과학
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• 제46권3호
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• pp.197-205
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• 2023

When taking X-rays, various auxiliary tools were used to fix a patient's exact shooting position and posture. In this study, we evaluated the usefulness of carbon fiber reinforced plastics(CFRP) 3K as a material of auxiliary tools by comparing poly methyl metha acrylate(PMMA), polycarbonate(PC), and CFRP 3K each of which has high radiolucency. X-ray radiolucencies were measured by stacking 1 mm panels of each material, and contrast to noise ratio(CNR) and signal to noise ratio(SNR) of images of each material were measured by comparing with None, which stands for images that are taken without any material. All three materials showed over 90% X-ray radiolucencies within 2 ㎜ thickness, and there was no significant difference. PC, PMMA and CFRP 3K had high CNR and SNR in order, and CFRP 3K showed the closest CNR and SNR to those of None. While taking X-rays, by using CFRP 3K material within 2 ㎜ thickness as a material of auxiliary tools, which are used to reduce re-shooting and X-ray exposure by fixing a patient's exact shooting position and posture and improve the quality of medical images, a high X-ray radiolucency of over 90% would be obtained, and the influence on the image could be minimized.

• 치과방사선
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• 제21권1호
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• pp.7-13
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• 1991

하악절흔 내측 함요는 하악골의 하악절흔 전, 내, 하방에 함몰된 양상으로 나타나는 정상 해부학적 구조물이다. 이 구조물에 대한 해부학적 중요성이나, 발생이 선천적인가 아니면 출생 후 발생되는 것인가에 대하여는 알려져 있지 않다. Langlais는 하악절흔내측함요는 파노라마 방사선사진상에서 절흔, 또는 소공 모양의 방사선투과상으로 나타난다고 하였지만 이는 하악사측방향 촬영상 등에서도 나타날 수 있는 해부학적 구조물이다. 파노라마 방사선사진에서는 익상판, 연구개, 기도, 그외 다른 조직 등의 중첩으로 인하여, 이 구조물의 발견 빈도가 낮아진다. 저자는 78개의 하악골에서의 발생빈도, 위치, 크기 등을 조사하고, 이를 파노라마 방사선사진촬영하여 그 발생 빈도를 조사하였으며, 치과환자 500명의 파노라마 방사선사진에서의 발생 빈도도 알아보았다. 1. 하악골에서의 발생빈도는 62%였다(편측성 28%, 양측성 33%). 2. 하악골의 파노라마 방사선사진상의 발생빈도는 33%였다(편측성 14%, 양측성 19%). 3. 하악절흔내측함요의 중심 위치는 하악절흔 하방 6.0㎜, 전방 3.8㎜였다. 4. 크기는 수직 7.8㎜, 수평 8.3㎜이였다. 5 치과환자들의 파노라마 방사선사진상에서의 발생 빈도는 24%였다(편측성 18%, 양측성 7%).

• 대한소아치과학회지
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• 제45권1호
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• pp.57-64
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• 2018

Pre-eruptive intracoronal resorption (PEIR)은 맹출 전 치아의 치관 내에서 나타나는 발달 상의 결함을 의미한다. 본 연구의 목적은 파노라마 방사선 사진의 미맹출 하악 제1대구치 협측 소와에서 PEIR로 의심되는 방사선 투과상과 맹출 중인 하악 제1대구치에서 협측소와의 수복 필요성과의 관계를 조사하는 것이다. 실험군은 맹출 중일 때 협측 소와에 한정된 수복이 필요한 병소가 관찰되었던 35개의 하악 제1대구치를 대상으로 하였고, 대조군은 맹출 후 건전했던 하악 제1대구치 64개를 포함하였다. 실험군은 대조군에 비하여 맹출 전 파노라마 방사선 사진에서 측정된 협측 소와의 크기가 통계적으로 유의하게 컸다. 실험군 내에서 성별, 나이, 치아형성단계, 수복 방법에 따른 협측 소와 크기의 유의한 차이는 없었다. Receiver operating characteristic 커브를 그렸을 때, 커브 아래 면적이 $0.813{\pm}0.047$으로 방사선 사진 상의 협측 소와 크기를 근거로 수복 필요성을 예측했을 때 중등도의 정확성을 보였다. 파노라마 방사선 사진에서 맹출 전 하악 제1대구치의 협측 소와 부위에서 방사선 투과상이 관찰되는 경우 임상적으로 PEIR을 의심하고 주기적인 관찰과 맹출 후 검사가 필요할 수 있다.

• 치과방사선
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• 제23권2호
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• pp.389-397
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• 1993

This is a report of multiple myeloma occurred in the left mandibular body and skull. 66-year-old patient was referred to our hospital with a complaint of painful swelling on the left mandibular body area. The author diagnosed it as a multiple myeloma by the clinical examination, radiographic findings, laboratory findings and the histopathological findings. The purpose of this report is to aid in the diagnosis of multiple myeloma and to aid to differentiate it from malignant tumours. The characteristic features are as follows: 1. In clinical examination, painful swelling was observed in left mandibular body area. 2. In radiographic findings, radiograms showed relatively ill-defined radiolucency without sclerotic border in left mandibular body area. And also represented multiple punched-out radiolucency in the skull and pathologic fracture of vertebral body on lumbar 3 level. 3. In histopathologic findings, infiltration of abnormal plasma cells was observed. 4. In laboratory findings, decreasing of albumin/globulin ratio, hypercalcemia, renal impairment was observed, but we could not find the Bence-Jones protein in urin.

• Imaging Science in Dentistry
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• 제39권3호
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• pp.169-173
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• 2009

The calcifying odontogenic cyst (COC) is a rare disorder of the jaws and shows various radiographic features. The purpose of this study is to describe the different radiographic appearances of 2 cases of COC. Case 1 was located in the posterior maxilla extending into maxillary sinus, showing unilocular radiolucency with a well-defined margin. Cortical bone expansion and thinning were prominent. Root resorption of adjacent teeth was apparent. Case 2 showed unilocular radiolucency with a calcified material. Calcification was supposed to be dystrophic dental hard structures, detected at the periphery of the lesion. Ghost cell and proliferation of ameloblastoma-like tissues were common features for these two lesions on histopathological findings. This reports presented common and atypical radiographic features of the COC.

• 치과방사선
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• 제26권2호
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• pp.181-189
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• 1996

Ameloblastic odontoma is a mixed odontogenic tumor, which is characterized as being extremely rare, displaying aggressive clinical behavior, resembling a mixed radiopaque and radiolucent radiographic appearance and containing both ameloblastoma and a composite odontoma. Seven-year-old boy complaining of delayed eruption of the left lower permanent 1st molar came to the department of Oral & Maxillofacial Radiology at Chonbuk National University Hospital. The list of our radiographic differential diagnosis included the dental follicle, compound odontoma, complex odontoma and cystic odontoma. The microscopic analysis showed the lesion with the characteristics of an ameloblastic odontoma. The obtained results were as follows; 1. The area was asymptomatic, but the delayed eruption of the left lower permanent 1st molar was observed. Radiographically, well-defined widened pericoronal radiolucency containing several tooth-like radiopacities involving the impacted left lower permanent 1st molar and well-defined round radiolucency containing irregular radiopaque mass were observed. 3. Histopathologically, several tooth-like structures, odontoma components with the area of typical enamel, dentin and pulp, and ameloblastic components with typical follicular ameloblastoma were observed.

• 치과방사선
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• 제27권1호
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• pp.123-140
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• 1997

The purpose of this study was to investigate effects of osteoporosis on fracture wound healing in the calcium deficient rat. To research the experiment some ten-week old Wistar strain rats with approximately 300 gms weight were selected. Then, the rats were divided into two groups: Normal diet group(rats given a normal diet before and after bone fracture) and Low calcium diet group(rats given a low calcium diet before and after bone fracture). Both groups had been provided with each diet for three weeks. When the rats became thirteen weeks old, the mandibular angle of rats in both groups was artificially fractured for test. The healing of fracture wounds was reviewed by using soft x-ray radiography and /sup 99m/Tc-MDP bone scan and also histopathologic examination. The obtained results were as follows : 1. The radiolucency of the fracture site for the Normal diet group started to decrease from the 14th day since the experiment was made, while the Low calcium diet group began decrease in the radiolucency from the 21st day of the experiment. The radiolucency for the Normal diet group disappeared at the 42nd day, but one for the Low calcium diet group disappeared at the 56th day of the experiment. 2. The highest uptake rate of /sup 99m/Tc-MDP stood at the 14th day of the experiment in the Normal diet group and the Low calcium diet group's maximum rate was recorded at the 21st day of the experiment. These both groups were gradually experiencing decrease in the uptake rate as the experiment time was going on. However, the uptake rate in the Low calcium diet group was lower than one in the Normal diet group. 3. For the Normal diet group, the newly formed trabeculae, which were similar to one of the surroundung bone, were seen at the 42nd day of the experiment. On the other hand, the Low calcium diet group showed at the 56th day of the experiment that the osteoporotic findings looked weak, irregular trabeculae, and also large bone marrow space were observed clearly. As a result of the above experiment, it is said that the healing of the fracture can be completed for both groups, the Normal diet group and the Low calcium diet group. However, the amount of the newly formed bone wound in the Low calcium diet group is rather decreased compared to one in the Normal diet group and at the same time the healing of the fracture is delayed in the Low calcium diet group. Consequently, for the successful healing of fracture in osteoporosis, it is considered that the management of the etiologic factors of osteoporosis must be preceded. The more study of calcium metabolism and functions of osteoblast and osteoclast needs to proceed on.

• 치과방사선
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• 제12권1호
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• pp.69-80
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• 1982

The author analyzed the morphologic changes of bone structures from 1256 radiographs of 314 patients with temporomandi.bular joint arthrosis, which were obtained by the oblique-lateral projection and orthopantomography. The interrelations of the bone changes and clinical symptoms were examined. Also, the positional relationships of condylar head, articular fossa and articular eminence in the mouth open and closed state were observed in the patients with bone changes. The results were as follows; 1. The most frequent bone change in the TMJ arthorsis was eburnation of cortical bone (35. 64%) of total cases). Then came bone surface erosion and localized radiolucency (26.18%), marginal proliferation (9.7%) and flattening of articular surface (9.58%) in that order. 2. The most frequent site of bone change was articular eminence (41.70%). The came condylar head (21.09%) and articular fossa (20.73%) in that order. 3. In the patients with bone changes, their clinical symptoms were pain (51.55%), clicking sound during mandibular movement (37.71%) and limited mandibular movement (10.73%). In the patients complaining pain, their radiographs showed eburnation of cortical bone (30.68%), bone surface erosion and localized radiolucency (27.45%) and flattening in the (30.68%), bone surface erosion and localized radiolucency (27.45%) and flattening of articular surface (10.68%). 4. The condylar positional changes in the TMJ arthrosis patients with bone changes were as follows: in the mouth closed !tate, there were the widening of joint space in 624 cases (50.00%), the narrowing of joint space in 543 cases (43.47%) and bone on bone relatioships in 82 cases (6.57%). In the mouth open state, there were forward positioning of the condyle in 332 cases (28.55%), limitation of movenent in 332 cases (28.55%), bone on bone relation- ships in 248 cases (21.31%) and downward positioning of condyle in 217 cases (18.66%). bone on bone relationships in 243 cases (21.32%) and downward positioning of condyle in 217 cases (18.66%). 5. In the TMJ arthrosis patients with bone changes, 1249 cases of abnormal condylar position in the mouth closed state and 1163 cases of abnormal condylar position in the mouth open state could be interpreted. so, for the radiographic interpretation of TMJ arthrosis, the reading of condylar positional changes as well as that of bond changes should be performed and their interrelations should be profoundly considered.

• Imaging Science in Dentistry
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• 제41권2호
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• pp.85-88
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• 2011

Central odontogenic fibroma is a rare odontogenic neoplasm that originates from odontogenic ectomesenchyme. Here, a case of central odontogenic fibroma in a 17-year-old male is reported. Since the present case showed a multilocular radiolucency with partially ill-defined border between the right mandibular condyle and the distal root of the right mandibular third molar, differential diagnosis involved a wide range of pathosis from benign lesions like ameoloblastic fibroma and odontogenic myxoma to more aggressive lesions such as desmoplastic fibroma, juvenile aggressive fibromatosis, or fibrosarcoma.