• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2016년도 춘계 종합학술대회 논문집
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• pp.367-368
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• 2016

본 연구는 임상에서 사용되어지는 두 가지의 불소 바니쉬를 비교연구 하였다. 또한 각각 치아표면에 10mg의 불소 바니쉬를 도포하였다. 각 대상자들의 타액의 불소이온유리농도는 1,3,12,24시간으로 채취하여 분석하였다. 각각의 불소 바니쉬를 도포한 타액 내 불소이온의 유리 누적량은 차이를 보였다. 본 연구는 현재 사용되어지는 불소 바니쉬를 선택함에 있어 기초자료로 사용될 수 있을 것이라 사료되어진다.

• Bulletin of the Korean Chemical Society
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• 제27권12호
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• pp.1967-1968
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• 2006

• 한국표면공학회지
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• 제28권5호
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• pp.289-299
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• 1995

The effects of phosphate coating have been studied on physical properties and corrosion resistance of painted aluminum alloy sheet for automobile body. The physical properties (surface roughness, paint adhesion, impact resistance and pencil hardness) and corrosion resistance(cyclic corrosion and filiform corrosion) were investigated. Phosphate coatings enhanced the physical properties of painted Al alloy sheet, especially paint adhesion after the 240hours water immersion test. Phosphate coating also markedly improved the resistance for cyclic corrosion and filiform corrosion of painted cold rolled steel and Zn-Ni plated steel sheet as well as painted Al alloy sheet. The corrosion resistance of painted Al sheets was varied with the concentration of free fluoride ion and metal additives like Ni and Mn in the phosphating bath. A maximum corrosion resistance was obtained at about 300ppm of fluoride ion and additives of Ni and Mn obviously increased the corrosion resistance of painted specimens.

• Restorative Dentistry and Endodontics
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• 제15권1호
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• pp.88-96
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• 1990

The purpose of this study was to investigate the fluoride release and solubility of glass ionomer cement associated with three pH media. For this study, GC Fuji II discs (20.0mm in diameter ${\times}$ 1.5mm thick) were immersed in pH 4.0 lactic acid, pH 7.0 distilled water and pH 10.0 KOH solutions for 1, 7, 14 and 28 days. The amount of fluoride release from the cement into three pH media were measured by fluoride specific ion electrode and the solubility was measured by weight loss of discs. The results were as follows: 1. The lower was the pH of media, the more was the amount of release of fluoride. 2. The amount of fluoride release was increased with time lapse. 3. After I day, the solubility was the highest, and after 7 days that was the least. 4. The lower was the pH of media, the more was the solubility, but there was no statistical difference in solubility according to the pH change.

• Restorative Dentistry and Endodontics
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• 제43권4호
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• pp.45.1-45.11
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• 2018

Objectives: This study was conducted to evaluate fluoride release and the micro-shear bond strength of resin-modified glass ionomer cement (RMGIC) in casein phosphopeptide-amorphous calcium phosphate (CPP-ACP)-remineralized caries-affected dentin (CAD). Materials and Methods: Exposed dentin surfaces of 30 human third molar teeth were divided into 2 equal groups for evaluating fluoride release and the micro-shear bond strength of RMGIC to CAD. Each group was subdivided into 3 equal subgroups: 1) control (sound dentin); 2) artificially demineralized dentin (CAD); 3) CPP-ACP remineralized dentin (remineralized CAD). To measure fluoride release, 15 disc-shaped specimens of RMGIC (4 mm in diameter and 2 mm in thickness) were bonded on one flat surface of the dentin discs of each group. Fluoride release was tested using ion chromatography at different intervals; 24 hours, 3, 5, 7 days. RMGIC micro-cylinders were built on the flat dentin surface of the 15 discs, which were prepared according to the assigned group. Micro-shear bond strength was measured after 24 hours water storage. Data were analyzed using 1- and 2-way analysis of variance and the post hoc least significant difference test (${\alpha}=0.05$). Results: Fluoride detected in solutions (at all intervals) and the micro-shear bond strength of RMGIC bonded to CPP-ACP-remineralized dentin were significantly higher than those bonded to artificial CAD (p < 0.05). Conclusions: Demineralized CAD consumes more fluoride released from RMGIC into the solution for remineralization than CPP-ACP mineralized dentin does. CPP-ACP increases the micro-shear bond strength of RMGIC to CAD.

• 대한소아치과학회지
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• 제24권1호
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• pp.204-219
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• 1997

The use of fluoride is one of the most effective methods for caries prevention. Fluoridation of public water supply has been recognized, for many years, as an effective way to reduce dental caries. The fluoride supplement has been recommended when the natural fluoride was unavailable or below the optimal range. However the mechanism of caries prevention by fluoride has not yet been clarified and it is well known that an overdose of fluoride results inacute and chronic toxicity, especially dental fluorosis. Fluoride mouthrinsing solution is widely used in dentistry due to its effectiveness in carrying anticariogenic action. Understanding the effects of fluoride mouthrinsing solution on human gingival fibroblasts will provide the safety rationale for its use during the caries preventive therapy. The purpose of this study was to evaluate the cytotoxic effect of fluoride mouthrinsing solution on the human gingival fibroblast in vitro. The human gingival fibroblasts were cultured from healthy gingiva on the extracted deciduous teeth of children. Cells were inoculated into a 24-well plate with $1{\times}10^4cells/well$ of medium at $37^{\circ}C$, 100% humidity, 5% $CO_2$ incubator for 24 hours. And the cells were counted by using the hemocytometer at each designed study. Human gingival fibroblasts were cultured in growth medium after one minute application range of 0.02%-0.2% NaF solution and 0.1% $SnF_2$ solution. The cells used in this study were between fifth to eighth passage number. The cell morphology was examined by inverted microscope and cell proliferation was measured by incorporating $[^3H]$-thymidine into DNA. DNA synthesis by human gingival fibroblasts was assessed by $[^3H]$-thymidine uptake assays while the cell activity was measured by MTT assay. Each concentrated fluoride mouthrinsing solution was estimated for its biocompatability with fibroblasts by the tissue culture technique. The results of this study were as follows : 1. It was observed that at 0.05%, 0.2% NaF mouthrinsing solution the cytoplasmic processes became globular. When 0.1% $SnF_2$ mouthrinsing solution was applied, the cytoplasmic process and cell morphology were disappeared. 2. DNA synthetic activity was reduced regardless of the concentration of the fluoride mouthrinsing solution. However, the result is statistically insignificant except 0.1% $SnF_2$ mouthrinsing solution(p<0.05). 3. Our results indicate that 0.02%, 0.05% concentrations of NaF mouthrinsing solution caused minimal cytotoxicity. But 0.2% NaF and 0.1% $SnF_2$ concentration were a significant difference between the cell activity in the experimental group and control group (p<0.05). 4. After appling 0.05% & 0.02% NaF fluoride mouthrinsing solution, cell activity was restored to the control groups level according to incubating time. The results suggest that direct exposure to fluoride solution inhibits gingival fibroblast activity. Therefore, for the most effective use of fluoride use, lowering the concentration of fluoride mouthrinsing is advisable because it maintains biocompatability and free ion in the oral fluid.

• 대한소아치과학회지
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• 제38권4호
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• pp.327-336
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• 2011

이 연구의 목적은 인체 안정성이 입증된 고분자제제인 폴리비닐알코올(PVA, Poly vinyl alcohol)로 얇은 박막을 제조하고 NaF을 첨가하여 불소를 함유한 고분자 접착 테잎(NaF-PVA)을 개발하여 피실험자의 구강 내에 도포 후 잔류하는 불소의 농도를 측정하고자 하는 것이다. 불소바니쉬(Cavityshiled$^{TM}$, 0.25 ml, Group 1)와 불소를 함유한 고분자 접착 테잎(NaF-PVA, Trial product, $1\;cm^2{\times}$ 12개, Group 2)을 각각 10명씩 치과대학 남학생의 치아(상악 12개, 순면)에 도포 후, 30분, 1시간, 2시간, 3시간, 4시간, 24시간, 48시간, 72시간 후 비자극성 전타액내 불소농도를 불소이온전극을 이용하여 측정하였으며 다음과 같은 결과를 얻었다. 1. 도포 후 30분과 1시간에서는 1군이 2군보다 높은 타액 내 불소농도를 보였으나 유의한 차이는 없었다(p>0.05). 2. 도포 후 2시간, 3시간, 4시간에서 2군이 1군보다 유의하게 큰 값을 보였다(p<0.05). 3. 도포 후 24시간 이후부터는 군간 통계적으로 유의한 차이를 보이지 않았다(p>0.05).

• Restorative Dentistry and Endodontics
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• 제22권1호
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• pp.193-208
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• 1997

Much evidence now exists from both in vivo and in vitro studies to support the claim that small caries lesions can 'heal'. But, there are still different views on the mechanism of remineralization. So in order to find the best condition for the remineralization of incipient dental caries in maximum efficient way, the author conducted the experiment which reveals the effect of pH on remineralization. 40 specimens of sound permanent teeth without demineralization or crack, $100{\mu}m$ in thickness, were immersed in lactic acid buffered demineralization solution for 4 days. Dental caries with surface zone and subsurface lesion were artificially produced. All specimens were immersed in lactic acid buffered remineralization solution of pH 4.0, 4.5, 5.0, 5.5 containg fluoride ion for 10 days. The results were obtaind by observing the specimens for every 10 days under polarized microscopy at x25. 1. Remineralization did not occur in entire depth of body of lesion at given degree of saturation and concentration of fluoride ion. 2. The pattern of remineralization has increased according to increase of pH. So it can be concluded that supersaturated solution with fluoride ion can be affected by pH in remineralization of enamel, and pH 5.5 seems to be very effective in remineralization of deep and surface zone of dental caries. However, more complex factors exist in achieving complete remineralization and further continuous researches are needed to clarify the factors.

• 한국결정성장학회지
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• 제30권6호
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• pp.232-236
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• 2020

본 연구에서는 광 발광특성이 우수하여 각종 광장치에 사용되고 있는 CaF2-Al2O3-B2O3-TiO2(CABT) 계 유리의 열처리 조건 및 결정상 생성에 따른 광학적 특성을 연구하였다. CAB 유리의 핵형성 및 결정성장을 제어하기 위해 핵형성제 TiO2를 첨가하고, 발광 특성을 향상시키기 위해 희토류 이온 Eu2O3를 첨가하였다. 열처리 조건에 따른 결정 성장 특성을 확인하기 위해 DTA 분석을 수행하였으며, 이에 따른 나노 크기 결정상 변화에 대한 XRD 및 SEM 분석을 수행하였다. 분석 결과 100 nm 크기의 결정생성은 발광강도를 향상시키지만 그 이상의 큰 결정 입자생성은 오히려 발광 특성을 저하시켰다.

• 대한환경공학회지
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• 제27권3호
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• pp.247-252
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• 2005

불소는 화학활성이 높아 반도체, 유리, 금속가공 등의 표면처리 및 세정제로 넓게 사용되고 있으며, 배출에 관해서는 수질환경보전법에 기준이 정해져 있다. 따라서 불소폐수는 일정한 수준 이하까지 불소를 제거하여 방출하여야 하며 일반적으로 고농도의 불소를 함유한 폐수처리에는 응집 침전법이 사용되어왔다. 그러나 이 방법은 10 ppm 이하의 저농도 불소 제거에는 효과가 없었다. 본 연구에서는 수용성 산을 함침시켜 소성한 변형 알루미나를 이용하여 저농도 제거가 어려운 불소 이온을 흡착에 의해 제거하는 기술을 개발하고자 하였다. 저농도 불소 이온을 제거하기 위해서 변형 알루미나를 이용하여 회분식 실험을 실행하였고, 흡착제 조성, 소성 온도, 흡착제의 투입량과 교반시간에 따른 제거효율을 조사하였다. 불소 이온의 가장 좋은 제거율은 황산으로 처리된 변형 알루미나에서 얻을 수 있었으며, 변형 알루미나 제조시의 적정한 소성온도는 $500^{\circ}C$였다. 또한 본 연구에서는 흡착등온식으로 널리 알려진 Freundlich식을 이용하여 흡착등온식을 구하였다. 회분식 실험을 통해 얻은 결과를 Freundlich 흡착 등온식에 적용한 결과 Freundlich 흡착 등온식의 상수 K값은 6.63이였고, 1/n은 0.29을 얻을 수 있었다.