• 치과방사선
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• 제7권1호
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• pp.27-30
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• 1977

To insure accuracy in dental roentgenographs, it is important that the patient's head position and angulation of the x-ray tube. In 1907 Cieszynski applied the rule of isometry to dental radiography and established that in the production of an accurate image of a tooth, the central ray must be porjected perpendicularly to a plane bisecting angle formed by the longitudinal axis of the tooth and the film plane. Proper exposure of the film is a part of the production of a good dental radiograph, and correct processing also makes an essential contribution to the quality of the radiograph. The author analysed the failure of exposure and processing results, and recommended followings. 1. The patient head must be positioned that occlusal plane are parallel with the horizontal floor. 2. Central ray must be projected to the objective tooth and supporting structure and projected as perpendicularly to tooth axis and film surface as possible. 3. In processing, the temperature of the solution and the processing time must be correct.

• 치과방사선
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• 제12권1호
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• pp.115-121
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• 1982

In the study of the focal trough of panoramic radiograph, using the Moritta compony Panex-EC a series of 48 exposures were: taken with the 6-18 brass pins placed in the holes of the plastic model plate, then eveluated by 4 observers. The author analyzed the focal trough defined by the sharpness criteria and calcuated the vertical and horizontal magnification range in the corrected focal trough. The results were as follows; 1. Continuous focal trough was not defined in the anterior region using a very high degree of sharpness. 2. As degree of sharpness used in the analysis became less, focal trough was continuous in the anterior and posterior regions, symmetrized bilaterally, and the widths of the focal trough increased more in the posterior region. e. As sharpness criteria were reduced, the percentage range of image magnification increased on both vertical and horizontal magnification, and especially the percentage range of horizontal magnification was greater than that of vertical magnification.

• 대한치과의사협회지
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• 제27권8호통권243호
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• pp.691-695
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• 1989

Raper가 1925년 소개한 교익방사선사진 촬영법은 나름대로의 독특한 특성을 갖고 있으므로 적절히 이용한다면 환자진료에 많은 도움을 받을 수 있을 것으로 생각되어 재조명해 보고자 한다.

• 대한치과의사협회지
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• 제43권12호통권439호
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• pp.822-837
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• 2005

• Journal of Periodontal and Implant Science
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• 제25권1호
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• pp.67-75
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• 1995

The progress of periodontal disease and the wound healing process after treatment result in alveolar bone bone change. So, detection of it is very important in the diagnosis and the radiograph of periodontal disease. Various effects have been made to assess the subtle alveolar bone change and digital subtraction radiography (DSR) has been reported to be the best method in evaluating it qualitatively and quantitatively. The present study was performed to estimate the detectable alveolar bone change qualitatively with digital subtraction radiography. For the in vitro study, 10 intraoral standard radiographs were taken from porcine dry mandible which a rectangular cortical bone chip of 0.1mm to 1.0mm thickness with 0.1mm increment was attached on the buccal surface. The radiographs without and with bone plates were reviewed at the same time by 10 observers and requested to detect the presence of cortical bone plates. Digital Subtraction radiograph was reviewed subsequently by using the DSR system(digital converter-256 grey-levels,DT 2851,Data Translation Co., U.S.A;IBM 386 ; CCD camera, FOTOVIX, Tamrom Co., Japan). The detectable thickness of cortical bone plate was O.4mm on the intraoral radiograph and 0.2mm on the subtaction images. For the human study, radiographs were taken from patients by using intraoral film holding device and aluminum reference wedge before and 3 month after bone graft and 1 week after osteoplasty. The grey level change was estimated in the subtraction images and calculated to aluminum equivalent thickness. The grey level of the grafted site was higher that that of healthy controls. Average grey levels of change on healthy controls were O.48mm aluminum equivalent. However, the amount of changes in grafted sites were 1.87mm aluminum thickness equivalent and in the site of osteoplasty were -1.49mm aluminum thickness equivalent. In conclusion, digital subtraction radiography was more effective in detecting as subtle change of alveolar bone than intraoral standard radiography. With the aid of quantitative analysis of digital subtraction radiography, alveolar bone resorption of apposition can be estimated during diagnosis and treatment of periodontally diseased patients.

• Tuberculosis and Respiratory Diseases
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• 제42권3호
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• pp.394-399
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• 1995

저자들은 고열 몇 호흡곤란을 호소하는 AIDS환자에서 흉부 X-선 사진상 정상소견을 정하였으나 기관지 내시경을 통한 기관지 폐포세척술과 폐조직 생검에서 pneumocystis carinii 포낭을 증명하고 조기 치료를 통하때 호전된 Pneumocystis carinii 폐렴 2예를 경험하여 이에 보고한다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제39권4호
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• pp.168-174
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• 2013

Objectives: The aim of this study is to investigate the correlation between 2-dimensional (2D) cephalometric measurement and 3-dimensional (3D) cone beam computed tomography (CBCT) measurement, and to evaluate the availability of 3D analysis for asymmetry patients. Materials and Methods: A total of Twenty-seven patients were evaluated for facial asymmetry by photograph and cephalometric radiograph, and CBCT. The 14 measurements values were evaluated and those for 2D and 3D were compared. The patients were classified into two groups. Patients in group 1 were evaluated for symmetry in the middle 1/3 of the face and asymmetry in the lower 1/3 of the face, and those in group 2 for asymmetry of both the middle and lower 1/3 of the face. Results: In group 1, significant differences were observed in nine values out of 14 values. Values included three from anteroposterior cephalometric radiograph measurement values (cant and both body height) and six from lateral cephalometric radiographs (both ramus length, both lateral ramal inclination, and both gonial angles). In group 2, comparison between 2D and 3D showed significant difference in 10 factors. Values included four from anteroposterior cephalometric radiograph measurement values (both maxillary height, both body height) and six from lateral cephalometric radiographs (both ramus length, both lateral ramal inclination, and both gonial angles). Conclusion: Information from 2D analysis was inaccurate in several measurements. Therefore, in asymmetry patients, 3D analysis is useful in diagnosis of asymmetry.

• 비파괴검사학회지
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• 제22권5호
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• pp.483-489
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• 2002

내부가 비어 있거나 유체로 절반 채워진 보온 및 비보온 배관에 대해 방사선 조사 방향에 따른 투과두께와 농도 변화를 전산 시뮬레이션 하였다. 결과적으로 내부가 비어있는 배관의 경우 투과필름에서 농도 변화가 연속적이며 대칭적인 반면, 유체가 절반 채워진 배관의 경우는 방사선 조사 방향에 따라 농도 변화가 비대칭적이며 크게 달라질 수 있음을 알았다. 인공 결함을 가공한 탄소강 배관 시편을 방사선원 Ir-192로 방사선투과시험 한 뒤 농도 변화를 측정하고 이론적으로 계산한 농도 변화와 비교한 결과 산란 방사선에 의한 영향이 큰 가장자리를 제외한 부분에서는 농도 변화를 이용한 두께 평가가 가능함을 확인하였다.

• 대한족부족관절학회지
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• 제17권1호
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• pp.34-39
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• 2013

Purpose: To evaluate the effectiveness of intraoperative stress test for diagnosis of occult Lisfranc injury. Materials and Methods: Between April 2009 and October 2012, 21 patients with occult Lisfranc injuries underwent intraoperative stress test and internal fixation. There were 11 males and 10 females with an average age of 45.3 years (range, 23~79 years). Injuries were caused by traffic accident in 10 cases, indirect force (twisting injury) in 8 cases, and crush in 2 cases, falling from a height in 1 case. Unstable injuries on stress radiograph in occult injury of Lisfranc joint were treated by open reduction or closed reduction and fixation with cannulated screw or K-wire. Radiological evaluation was assessed according to preoperative and postoperative diastasis between $1^{st}$ and $2^{nd}$ metatarsal base. Results: Assoicated injuries were 9 cases of metatarsal fractures, 6 cases of cuneiform fractures and 6 cases of both metatarsal and cuneiform fractures. Medial and middle column fixation was in 13 cases, and three columns fixation was in 8 cases. Initial diastasis between $1^{st}$ and $2^{nd}$ metatarsal base was 2.8 mm (1.3~4.7 mm) on AP radiograph and postoperative diastasis between $1^{st}$ and $2^{nd}$ metatarsal base was 1.2 mm (0.5~2.4 mm) on AP radiograph. Conclusion: Even there is no sign of clear Lisfranc injury, it is necessary to pay attention and give evaluation on circumstances of occult Lisfranc injuries with metatarsal or cuneiform fractures. Intraoperative stress test is helpful to diagnose an occult Lisfranc injury. For unstable injuries on stress radiographs of occult Lisfranc joint injury, operative treatment with open or closed reduction and internal fixation is useful method.

• 박물관보존과학
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• 제7권
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• pp.11-24
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• 2006

판갑은 고대의 무기와 철제품 제작기술을 그대로 반영하는 중요한 문화재이다. 철제갑옷 중 횡장판갑의 출토사례는 매우 드물며 망이산성 출토 판갑처럼 그 형태가 완형인 유물은 그리 많지 않다. 이번 보고서에서는 응용 가능한 비파괴 방사선 조사에 의한 횡장판갑의 방사선사진 및 과학적 보존처리를 통하여 나타나는 고대 판갑제작기술을 검토해 보았다. 7단 구성의 망이산성 출토 판갑은 고리경첩으로 우전동이 개폐되는 형식이다. X-선 사진의 판독결과 판겹침과 천공간격으로 고대판의 철포복륜 및 우측협부의 혁포복륜이 확인되었으며, 착장시 어깨걸이를 연결한 것으로 보이는 투공도 관찰되었다. 특히 천공과 병뉴기법에 있어, 하나의 병이 세판 이상을 연접하는 것을 피하고 있음을 확인하였다. 이는 기술적인 한계를 극복하고 판갑의 기능을 살렸음을 보여주는 중요한 자료이다.