• Journal of dental hygiene science
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• v.15 no.5
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• pp.536-541
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• 2015

The purpose of this study was to evaluate the marginal and internal gap of Cobalt (Co)-Chromium (Cr) sintering metal coping fabricated by dental computer-aided design/computer-aided manufacturing systems. Abutment tooth 46 of universal numbering system was selected for the study. Twenty Co-Cr metal copings of two groups were manufactured and scanned. Co-Cr cast metal copings (CCM) group of ten were fabricated using investment, burnout and casing after subtractive manufacturing of wax block. Also, Co-Cr sintering metal copings (CSM) group of ten were fabricated using sintering processing after subtractive manufacturing of Co-Cr soft metal bock. Marginal and internal gap of Co-Cr metal copings of twenty were measured by digital microscope (${\times}160$) with silicone replica technique. The data was analyzed from IBM SPSS Statistics ver. 22.0 Statistical software for Mann-Whitney U test (${\alpha}=0.05$). $Mean{\pm}standard$ deviation of marginal gap of CCM group was $90.12{\pm}61.73{\mu}m$ of CSM group was $60.17{\pm}24.83{\mu}m$. However, two groups was statistically not different (p>0.05). This study showed that CSM group was clinically acceptable adaptation.

• International Journal of Clinical Preventive Dentistry
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• v.14 no.4
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• pp.247-255
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• 2018

Objective: Osseointegration is essential process for successful implants and effects to implant in long term, therefore, passive fitness of good prosthesis is necessary. To make a good prosthesis, at first it should be done a sectioned casting and then joined method of sectioned casting body is recommended. Methods: In this study, to provide the fundamental data on stable connection method for successful implants, the author tested fitness of casting body, and compared difference between gas soldering technique and laser welding technique. Results: In fitness test of 2 abutment (test A, C), gas soldering group's fitness in the opposite part of connection was worse than laser welding group. In fitness test of 3 abutment (test B, D), gap distance was increased both in gas soldering technique and laser welding technique. Gap distance at the connecting part and the opposite part of the abutment in gas soldering technique was worse than laser welding technique and the more additional abutment, the worse gap distance in gas soldering technique. In fitness test of 3 abutment (test B, D), there's little variation in No. 2 abutment when connecting soldering process was done and there's little influence on already soldered connection part when the additional soldering connection was done. Conclusion: On weak loading condition and the part which is needed an accuracy, laser welding technique is more effective and on long-span prosthesis and frequent chewing loading part, laser welding technique is recommended first and applying additional gas soldering technique would be better for making much more successful prosthesis.

• Journal of Environmental Impact Assessment
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• v.21 no.5
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• pp.631-648
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• 2012

The integrative ecological approaches of chemical assessments, physical habitat modelling, and multi-metric biological health modelling were applied to Gwanpyeong Stream within Gap-Stream watersheds to evaluate environmental impacts on the constructions of residential and commercial complex. For the analysis, the surveys conducted from 45 sites of reference streams within the Gap-Stream watershed and 3 regular sites during 2009 - 2010. Physical habitat health, based on the habitat model of Qualitative Habitat Evaluation Index(QHEI) declined from the headwaters(good - fair condition) to the downstream(poor condition). Chemical water quality, based turbidity and electric conductivity(EC), was degraded toward to the downstream, and especially showed abrupt increases, compared to the values of control streams(CS). Also, concentrations of chlorophyll-a in the downstreams were greater compared to the control stream(CS), indicating an eutrophication. Biological health conditions, based on the Index of Biological Integrity(IBI) using fish assemblages, averaged 19.3 which is judged as a fair condition by the biological criteria of the Ministry of Environment, Korea. The comparisons of model metric values in sensitive species and riffle-benthic species on the Maximum Species Richness Line(MSRL) of 45 reference streams indicated a massive disturbances in all sampling locations. Also, tolerance guild and trophic guild analyses suggest that dominances of tolerant species and omnivores were evident, indicating a biological degradation by habitat disturbances and organic matter pollutions. There was no distinct longitudinal variations of IBI model values from the headwater to the downstream in spite of slight chemical and habitat health gradients among the sampling sites. Overall, integrative ecological health(IEH) scores, based on the chemical, physical, and biological parameters, were low compared to the 45 reference streams due to physical and chemical disturbances of massive constructions of the residential and commercial complex. This stream, thus showed a tendency of typical urban streams which are disturbed in the chemical water quality, habitat structures, and biological integrity. Effective stream management plans and restoration strategies are required in this urban stream for improving integrative stream health.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 2004.05a
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• pp.259-259
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• 2004

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2004.05a
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• pp.118-118
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• 2004

• Journal of Korean society of Dental Hygiene
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• v.8 no.4
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• pp.141-151
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• 2008

The purpose of this study was to examine the oral health awareness and oral health care of health-related and health-unrelated majors in an attempt to stress the importance of oral health education and boost the efficiency of oral health care. The subjects in this study were 363 college students. Out of the selected students, 174 were health-related majors, and 189 weren't. After a survey was conducted, the collected data were analyzed for the purpose of comparison, and the following findings were given: 1. Concerning daily mean toothbrushing frequency, the largest number of the male students who accounted for 55.2 percent brushed their teeth once a day on average, and the greatest number of the female students who represented 52.9 percent did that twice a day. As for the influence of their major, the largest group of the health-related majors who numbered 89(51.1%) brushed their teeth twice a day, and the greatest group of the health-unrelated majors who numbered 93(49.2%) did that once a day. The gaps between them were statistically significant(p<0.05). 2. As to the length of toothbrushing time by gender, it took more than two or three minutes for the largest groups of the male and female students that respectively numbered 96(76.8%) and 184(77.3%) to do toothbrushing(p<0.01). The greatest groups of the male and female students that respectively numbered 72(57.6%) and 183(76.9%) brushed their teeth after meals. 3. In regard to oral hygiene supplies, the largest groups of the health-related and health-unrelated majors that respectively numbered 78(44.8%) and 115(60.8%) had chewing gum and candy with them. As to the use of oral hygiene supplies, 99 health-related majors(56.9%) and 133 health-unrelated majors(70.4%) didn't put oral hygiene supplies to use. Thus, the use of oral hygiene supplies was statistically less common among the health-unrelated majors, and the gap between the two was significant(p<0.01). 4. As for health-related concern by gender, the largest group of the male students that numbered 56(44.8%) showed the most interest in preventing dental caries, and the greatest group of the female students that numbered 103(43.3%) were most concerned about tooth whitening. The gap between the male and female students was statistically significant(p<0.05), but the track of their major made no statistically significant difference to that. 5. Regarding the experience and awareness of scaling, the largest number of the students never got their teeth scaled regardless of gender and major, and the greatest group didn't care about scaling irrespective of gender and major, either, though they considered it advisable to do.

• Journal of dental hygiene science
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• v.14 no.2
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• pp.207-213
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• 2014

How to eliminate health disparity to ensure health equity is one of major issues that are handled across the world. The purpose of this study was to examine any possible differences in self-rated oral health state according to socioeconomic status and the relationship between the two based on the data of the 5th National Health & Nutrition Examination Survey of 2010~2012. As for differences in self-rated oral health state according to sociodemographic characteristics, the women considered themselves to be in poorer oral health than the men. The older respondents found themselves to be in poorer oral health, and there was a tendency that the respondents who were less educated and whose household income was smaller rated their own health as worse. When a logistic regression analysis was made to determine influential factors for self-rated oral health status, the women perceived they were in better oral health than the men did, and the better-educated respondents were more likely to consider themselves healthier. Concerning disparities in self-rated health state according to income level, there were broader differences in that regard according to an increase of income. The findings of the study illustrated that there was oral health inequity according to social stratum. It's required to make a nationwide effort to promote national oral health, and appropriate support should especially be provided for disadvantaged people at the same time in order to get rid of the gap in oral health among different social classes, as there is a yawning gap between them and the other classes.

• Journal of Digital Convergence
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• v.14 no.1
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• pp.321-326
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• 2016

The aim of this study was to evaluate the association between TNF polymorphism and generalized aggressive periodontitis (GAP) in Korean subjects. The study population consisted of 60 subjects with GAP and 81 reference group. Genomic DNA was extracted from the buccal swabs and the polymorphisms of $TNF-{\alpha}-308$, -238 promoter genes, $TNF-{\beta}+252$ and TNFR 2+587 were determined by PCR-RFLP using restriction enzymes. The genotype distribution in the GAP were 3.2%, 38.7%, and 82.35% for A/A, A/G and G/G genotypes of $TNF-{\alpha}-308$. At the position of $TNF-{\alpha}-238$, the genotype distribution in the GAP were 25.5% and 74.5% for A/G and G/G genotypes. Allele A frequency of $TNF-{\alpha}-238$ were 67.6% in GAP and 72.2% in reference group. According to these findings, the polymorphism at $TNF-{\alpha}-308$ and -238 may be associated with GAP in Korean.

• Health Policy and Management
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• v.9 no.4
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• pp.140-156
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• 1999

The purpose of this article was to review the basic concept of the SERVQUAL scale and to evaluate its usefulness in health care settings. The SERVQUAL scale was developed by Parasuraman et al. in 1988. Its purpose was to provide an instrument for measuring the quality of service that would apply across a broad range of services with minor modifications in the scale. The SERVQUAL scale is based on gap theory, which indicates the difference between consumers' expectations and their assessment of the actual performance of a specific firm. It has five dimensions to define service quality. These dimensions include: (1) tangibles' (2) reliability' (3) responsiveness' (4) assurance' (5) empathy. While the SERVQUAL scale has been tested in a number of health care settings. the findings have been mixed. So. health care marketers should be cautious in their use of the SERVQUAL scale. However, it is rare to find instruments that are as well validated as SERVQUAL appears to be. As well the SERVQUAL scale provides valuable information about the quality of health care service.

• Journal of Mushroom
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• v.15 no.4
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• pp.178-182
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• 2017

Good Agricultural Practices (GAP) is the world's leading quality certification for food safety. Since its introduction in Korea in 2006, its importance has been increasing every year. In particular, food safety issues are becoming increasingly important in society, and food safety is directly linked to health. The core of GAP certification is the traceability of the production, distribution, and consumption of hazardous materials, including pesticide residues, heavy metals, and microbes. In the present study, pesticides and heavy metals in button mushroom (Agaricus bisporus) and associated cultivation materials were analyzed. Tricyclozole (0.0144 ppm), flubendiamide (0.147 ppm), and trifloxystrobin (0.0340 ppm) were detected in rice straw and wheat straw, and carbendazim (0.0142 ppm) was detected in mixed wheat straw and rice straw medium. Lead and cadmium were detected at levels higher than the standard level in rice straw and mixed medium. However, lead and cadmium were not detected in mushrooms, and levels of arsenic and mercury were below the safety limit. Therefore, it was confirmed that the residual pesticides and heavy metals are safely managed in the investigated mushroom species. The results of the present study suggest that if these materials are adequately managed in the surroundings during cultivation, all hazardous materials can be managed during mushroom production.