• 대한방사선기술학회지:방사선기술과학
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• 제27권4호
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• pp.37-41
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• 2004

목 적 : 측정을 통한 장치의 성능관리 평가로 임상실무에서의 능력배양과 정확한 관전압, 조사시간, 출력선량을 측정하는 기술을 익히고 병원에서 사용 중인 간접촬영용 X-선 발생장치 성능현황을 파악하기 위함이다. 재료 및 방법 : 관전압, 조사시간, 출력선량 측정기를 이용하여 10개 대학병원 간접촬영용 X-선 발생장치(원내,외 각 10대)를 이용하였다. 결 과 : 관전압 정확도 시험 PAE 판정에 의해 부적합한 간접촬영기는 3대가 나왔으며, 조사시간의 정확도 시험에서는 2대, 또한 조사선량의 재현성 시험에서도 조사선량에 대한 변동계수를 계산한 결과 3대가 나왔다. 3가지 성능검사에서 원외(이동차량)의 부적합한 간접촬영기는 5대, 원내는 3대로 원외(이동차량)의 간접촬영기가 원내보다 부적합한 것이 높게 나타났다. 결 론 : 간접촬영기의 성능을 일정하게 유지함으로서 방사선 피폭경감, 화질관리, 재촬영 감소 등에 의해 환자에게 양질의 의료서비스를 제공할 수 있는 여건을 마련할 수 있을 것이다. 따라서 정기적인 성능검사가 필요하다고 사료된다.

• The Journal of Advanced Prosthodontics
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• 제4권1호
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• pp.18-23
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• 2012

PURPOSE. The purpose of this prospective study was to evaluate the effect of early loading on survival rate or clinical parameter of anodic oxidized implants during the 12- month postloading period. MATERIALS AND METHODS. Total 69 implants were placed in 42 patients. Anodic oxidized implants (GS II, Osstem Cor., Busan, Korea) placed on the posterior mandibles were divided into two groups, according to their prosthetic loading times: test group (2 to 6 weeks), and control group (3 to 4 months). The implant survival rates were determined during oneyear postloading period and analyzed by Kaplan-Meier method. The radiographic peri-implant bone loss and periodontal parameters were also evaluated and statistically analyzed by unpaired t-test. RESULTS. Total 69 implants were placed in 42 patients. The cumulative postloading implant survival rates were 88.89% in test group, compared to 100% in control group (P<.05). Periimplant marginal bone loss (T: $0.27{\pm}0.54$ mm, C: $0.40{\pm}0.55$ mm) and periodontal parameters showed no significant difference between the groups (P>.05). CONCLUSION. Within the limitation of the present study, implant survival was affected by early loading on the anodic oxidized implants placed on posterior mandibles during one-year follow-up. Early implant loading did not influence peri-implant marginal bone loss, and periodontal parameters.

• Imaging Science in Dentistry
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• 제51권2호
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• pp.137-148
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• 2021

Purpose: This study aimed to assess the computer monitors used for analysis and interpretation of digital radiographs within the clinics of the Oral Health Centre of Western Australia. Materials and Methods: In total, 135 computer monitors(3 brands, 6 models) were assessed by analysing the same radiographic image of a combined 13-step aluminium step wedge and the Artinis CDDent 1.0^® (Artinis Medical Systems B.V.^®, Elst, the Netherlands) test object. The number of steps and cylindrical objects observed on each monitor was recorded along with the monitor's make, model, position relative to the researcher's eye level, and proximity to the nearest window. The number of window panels blocked by blinds, the outside weather conditions, and the number of ceiling lights over the surgical suite/cubicle were also recorded. MedCalc^® version 19.2.1 (MedCalc Software Ltd^®, Ostend, Belgium, https://www.medcalc.org; 2020) was used for statistical analyses(Kruskal-Wallis test and stepwise regression analysis). The level of significance was set at P<0.05. Results: Stepwise regression analysis showed that only the monitor brand and proximity of the monitor to a window had a significant impact on the monitor's performance (P<0.05). The Kruskal-Wallis test showed significant differences (P<0.05) in monitor performance for all variables investigated, except for the weather and the clinic in which the monitors were placed. Conclusion: The vast performance variation present between computer monitors implies the need for a review of monitor selection, calibration, and viewing conditions.

• 대한전자공학회논문지SP
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• 제47권3호
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• pp.70-80
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• 2010

본 논문에서는 치과용 의료시스템(Dental PACS)에서 필요한 시계열 분석(Subtraction Radiography) 방법에 기반 하여 기존의 연구에서 갖지 못했던 영상정렬의 자동화 방안과 미세변화 검출 방안을 제안한다. 제안된 방법은 기존의 단일 템플릿 방식의 문제점을 해결하기 위해 인공치아 및 자연치아의 기하학적 형태 정보를 이용하여 각 치아에 대한 관심영역을 획득하고 획득된 관심영역을 기준으로 지식 기반(knowlege-based)의 다중 템플릿(multi-template) 방식의 정합을 통해 치아 주위에서 발생되는 미세변화를 빠르고 정확하게 검출할 수 있다. 실험결과 제안된 방법은 신속하고 정확하게 치아 주위의 미세변화에 대한 검출이 가능하였고, 보다 객관적이고 정량적인 결과를 제시할 수 있음을 보여주었다.

• 한국추진공학회지
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• 제11권1호
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• pp.34-42
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• 2007

초음파를 이용한 추진기관의 비파괴검사는 X-ray 검사에 비하여 경제성이 우수하고, X-ray 검사 시 취약한 미접착, 손상 등의 결함 검출이 우수한 편이다. 그리고 전용 시설 없이 현장에서 실시간으로 검사가 가능하며 방사선 작업에 비하여 안전한 방법이다. 본 논문에서는 고체 추진제에 대한 초음파 특성을 분석하고, 추진제/라이너 미접착에 대한 내측과 외측 검사 방법 및 추진제 손상에 의한 미세 크랙 검출에 대하여 실험 및 분석하였다. 실험 결과, 추진제/라이너 미접착에 대한 내.외측 검사에 있어서 검출 가능성을 보였으며, 그리고 손상에 의한 추진제 미세 크랙도 초음파의 감쇠특성을 이용하여 검출 가능함을 보였다.

• Journal of Periodontal and Implant Science
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• 제40권1호
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• pp.33-38
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• 2010

Purpose: The purpose of this study was to observe and quantify the expression of interleukin-4 (IL-4), interferon-$\gamma$ (IFN-$\gamma$), and tissue inhibitor of matrix metalloproteinase-2 (TIMP-2) in the gingival tissue of patients with type 2 diabetes mellitus (DM) and healthy adults with chronic periodontitis. Methods: Twelve patients with type 2 DM and chronic periodontitis (Group 3), twelve patients with chronic periodontitis (Group 2), and twelve healthy individuals (Group 1) were included in the study. Clinical criteria of gingival (sulcus bleeding index value, probing depths) and radiographic evidences of bone resorption were divided into three groups. The concentrations of cytokines were determined by a western blot analysis and compared using one-way ANOVA followed by Tukey's test. Results: The expression levels of IFN-$\gamma$ and TIMP-2 showed an increasing tendency in Groups 2 and 3 when compared to Group 1. On the other hand, the expression of IL-4 was highest in Group 1. Conclusions: The findings suggest that IFN-$\gamma$ and TIMP-2 may be involved in the periodontal inflammation associated with type 2 DM. IL-4 may be involved in the retrogression of the periodontal inflammation associated with type 2 DM.

• 한국임상수의학회지
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• 제18권1호
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• pp.70-73
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• 2001

Five-month-old a female mongrel puppy weighing 3.5 kg showed no systemic disorder and particular discomfort except abdominal distension at the first visit. On physical examination an irregular abdominal mass was palpated. One month later she was clumsy and uncoordinated. In addition, lethargy and anorexia were appeared. Then she became comatose and died in spite of initial therapy. In radiographic examination enlargement of both sides of kidney was observed. The hematological examination the dog had WBC of 16,250/$\mu$l, RBC of $7.2{\times}10^6$ $\mu$l, PCV of 32%, total protein of 8.0 g/dl, and fibrinogen of 900 mg/dl. In serum chemistry BUN was 87.4 mg/dl and creatinine was 5.1 mg/dl. Urinalysis revealed pH of 5.6, SG of 1.009 and protein of 500 mg/dl. In urine sediment test many RBCs, leukocytes, inflammatory cells and a few epithelial cells were observed. On histopathologic examination the size of right and left kidney were 15 cm, 16 cm in length, 6 cm, 6 cm in widths, respectively. Both sides of kidney were filled with brown-orange fluid and had irregular capsular surface. The cysts of various sizes were located throughout the cortex and medulla. No abnormality was found in any other organs. Histologically, cyst was lined by cuboidal to slightly flattened tubular epithelium and surrounded by mature fibrous connective tissue. Glomeruli, tubule and renal pelvis remained normal between cysts and exfoliated epithelial cells.

• 대한치과교정학회지
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• 제47권5호
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• pp.334-339
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• 2017

Objective: Teeth discoloration is a rare orthodontic complication. The aim of this study was to report the clinical progression of discoloration during orthodontic treatment. Methods: Discolored teeth, detected during orthodontic treatment between January 2003 and December 2012 by a single dentist using similar techniques and appliances, were analyzed. Results: The total number of teeth that showed discoloration was 28. Progression of discoloration was evaluated in only 24 teeth that were observed without any treatment. During the observation period, the discoloration "improved" in 8 of the 24 teeth (33.3%) and was "maintained" in 16 (66.6%). The electric pulp test performed at the time of initial detection of discoloration showed 14.3% positivity, which improved to 21.4% at the final follow-up. None of the initial and final follow-up radiographic findings showed any abnormalities. Conclusions: When teeth discoloration is detected during orthodontic treatment, observation as an initial management is recommended over immediate treatments.

• Journal of Periodontal and Implant Science
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• 제26권3호
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• pp.725-734
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• 1996

The present study has been performed to revise the forms of early-onset periodontitis(EOP) into the homogeneous phenotypic subsets by cluster analysis using sets of clinical parameters. Retrospective radiographic interproximal alveolar bone levels were measured from cemento-enamel junctions on patients who have previously been diagnosed as having one of EOP during last 5 years. Mean interproximal bone levels(BL) and mesial bone level(Ratio) of 1st molars relative to mean interproximal bone levels of adjacent teeth(lst and 2nd premolars and canines)were calculated on each patient. Using parameters BL and Ratio(BR group) or BL, Ratio and age(BRA group), cluster analysis was performed to revise EOP patients into homogeneous subsets. At least three or four cluster could be homogeneously formed both in BR or BRA groups with statistically significant differences in parameters used among clusters as evidenced by MANOVA test. It was shown that the greater the BL, the smaller the Ratio was. It was also evident that mean interproximal bone levels were lowest aroud 1st molars and/or incisors regardless of cluster types. The results has provided cluster-based studies for identifying laboratory markers responsible for the development of EOP subsets.

• 박물관보존과학
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• 제5권
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• pp.17-22
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• 2004

일제시대에 발굴되어 여러 편으로 분리되어 있던 철제용기를 보존처리하였다. 보존처리를 통하여 유물을 안정화시키고, 본래의 형상을 복원하였다. 보존처리 결과 철제용기는 굽이 있으며 구연부에 턱이 있고 안으로 오므라드는 유선형이었다. X-선 투과검사 결과 주조과정에서 기공이 많이 발생한 것이 관찰되었으며, 금속조직을 통해 재질이 초정흑연을 가진 과공정 백주철임을 알 수 있었다.