• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.4
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• pp.600-606
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• 2002

The purpose of this study was to evaluate the diagnostic validity of an incipient occlusal caries using argon laser fluorescence. Extracted human premolars and molars with enamel carious lesion of occlusal surface were assessed using visual examination, visual examination with probing, argon laser fluorescence and histologic depth of carious lesion. The results in each of all the three detection methods were compared to the assessment of histologic depth of carious lesion using polarized microscope. The results from the present study can be summarized as follows; 1. There was highly correlation between the histologic depth of occlusal caries and all three detection methods(P<0.01). 2. The reproducibility(kappa value) of the visual examination, visual examination with probing and argon laser fluorescence between the histologic depth of occlusal caries was 0.189, 0.128, 0.472. The highest correlation was seen between detection of occlusal caries by argon laser fluorescence and histologic scores by polarized microscope. The results from this study indicated that argon laser fluorescence considered to be accurate and reliable method in detecting occlusal caries.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.2
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• pp.323-330
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• 2004

The purpose of this study was to evaluate the diagnostic validity of early proximal caries lesions using laser fluorescence and whether the detection could be enhanced using a fluorescent dye. Direct visual examination and bitewing radiograph were used for comparison. The subjects of this study were 30 children of $3{\sim}9$ years old. Laser fluorescence and dye-enhanced laser fluorescence(mixed wavelength of 488 and 514 nm) were used and viewed through glasses(excluding wavelength<520 nm). For dye-enhanced laser fluorescence a 0.075% sodium fluorescein dye was applied before examination. Proximal caries lesion of each subject was assessed using visual examination, bitewing radiograph, laser fluorescence, and dye-enhanced laser fluorescence. The results in the three detection methods were compared to the assessment of bitewing radiograph. The results from the present study can be summarized as follows: 1. There was highly correlation(r=0.725-0.911) between the bitewing radiograph and all three detection methods(p<0.05) 2. The reproducibility(kappa value) of the visual examination, laser fluorescence and dye-enhanced laser fluorescence comparing with bitewing radiograph of proximal caries was 0.451, 0.683, 0.772, respectively. There was highest correlation between dye-enhanced laser fluorescence and bitewing radiograph for detection of proximal caries. The results from this study indicated that the dye-enhanced laser fluorescence considered to be accurate and reliable method in detecting proximal caries.

• Journal of Chest Surgery
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• v.32 no.8
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• pp.726-731
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• 1999

Background: The distinction between non-invasive and invasive or thymic carcinoma has been severely compromised by lack of objective morphological criteria. A reliable biological marker of tumor aggressiveness is, therefore, mandatory for predicting tumor behavior. Material and Method: Thirty thymic epithelial tumors, including 7 non-invasive thymoma, 10 invasive thymoma, and 13 thymic carcinoma of the Rosai's classification; and 5 stage I, 7 stage II, 2 stage III, and 3 stage IVa of the Masaoka stage of thymoma were investigated for expression of bcl-2 and p53 proteins by immunohistochemistry. Result: The thymic epithelial cells showed positive immunostain for bcl-2 in 0 (0%), 3 (30%), 8 (61.5%) of categories in the Rosai's classification respectively and in 0 (0%), 1 (14.3%), 2 (100%), 0 (0%) of stage I, II, III, IVa of the Masaoka stage respectively. Thymic carcinoma, and high stage thymoma had significantly higher proportion of bcl-2 expression than thymoma (p=0.021) and low stage thymoma (p=0.011). However, p53 showed no correlation with the histological subtypes nor with clinical aggressiveness. Bcl-2 expression appeared to be positively correlated with p53 immunoactivity (p=0.007, kappa=0.525). Conclusion: These date indicate that bcl-2 expression correlates with aggressiveness in thymic epithelial tumors, but further studies on mutation of p53 protein is necessary because bcl-2 expression appeared to be positively correlated with p53 immunoactivity.