• The Journal of the Korean dental association
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• v.39 no.11 s.390
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• pp.915-925
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• 2001

불소의 적절한 활용을 통하여 미국인들의 구강건강이 확실하게 증진되었으며 수돗물의 인공적인 불소참가 사업은 지난 2000년 동안에 건강과학이 이룩한 가장 획기적인 건강관리 예방사업으로 인정되었다. 음료수에 불소를 적정량 첨가하여 치아우식증을 퇴치하기 위하여 적극적 예방책을 마련함으로써 치과의학의 과학적인 연구의 기틀을 확고히 하여 치과의학이 현대 건강과학의 지도적 위치를 확보하는 과정에 중요한 임무를 담당했다. 그러므로 미국의 중앙건강관리 및 예방 연구소는 정기적으로 불소사용과 관련된 연구 업적들에 대하여 관련 분야의 세계적인 학자들로 하여금 조리 정연하게 주기적으로 분석 검토하여 구강건강을 향상시킬수 있는 방안을 제시하기 위하여 불소사용법에 대한 안내서를 마련하고 있다. 미국 중앙 질병 관리 및 예방연구소는 평생을 불소에 관한 연구를 하고 있는 11명의 전문가들과 긴밀한 연락을 취하면서 22명의 과학자들과 함께 그 동안에 발표된 관계문헌 270개를 분석 검토하여 2년동안에 걸쳐 작성한 최근의 불소 사용 안내서를 지난 2001년 8월 17일 발표했다. 그 내용이 중요하고 한국의 치과의사들에게 큰 도움이 되리라고 확신하기 때문이다. CDC의 허락을 받고 한글판을 작성하게 되었다. 한국의 관심 있는 독자들의 이해를 돕기 위하여 더욱 자세한 내용을 알고자 하는 분들이 실무진에 참여한 연구자들 및 과학자들과 직접 접촉할 수 있도록 그들의 직책과 현재의 소속을 밝혔으며 이 안내서에 사용된 문헌 270개 참고문헌 전체를 소개한다

• The Journal of the Korean dental association
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• v.40 no.1 s.392
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• pp.42-53
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• 2002

불소의 적절한 활용을 통하여 미국인들의 구강건강이 확실하게 증진되었으며 수돗물의 인공적인 불소첨가 사업은 지난 2000년 동안에 건강과학이 이룩한 가장 획기적인 건강관리 예방사업으로 인정되었다. 음료수에 불소를 적정량 첨가하여 치아우식증을 퇴치하기 위하여 적극적 예방책을 마련함으로써 치과의학의 과학적인 연구의 기틀을 확고히 하여 치과의학이 현대건강과학의 지도적 위치를 확보하는 과정에 중요한 임무를 담당했다. 그러므로 미국의 중앙건강관리 및 예방 연구소는 정기적으로 불소사용과 관련된 연구 업적들에 대하여 관련 분야의 세계적인 학자들로 하여금 조리 정연하게 주기적으로 분석 검토하여 구강건강을 향상시킬 수 있는 방안을 제시하기 위하여 불소사용법에 대한 안내서를 마련하고 이다. 미국 중앙 질병 관리 및 예방연구소는 평생을 불소에 관한 연구를 하고 있는 11명의 전문가들과 긴밀한 연락을 취하면서 22명의 과학자들과 함께 그 동안에 발표된 관계문헌 270개를 분석 검토하여 2년 동안에 걸쳐 작성한 최근의 불소 사용 안내서를 지난 2001년 8월 17일 발표했다. 그 내용이 중요하고 한국의 치과의사들에게 큰 도움이 되리라고 확신하기 때문에 CDC의 허락을 받고 한글판을 작성하게 되었다. 한국의 관심 있는 독자들의 이해를 돕기 위하여 더욱 자세한 내용을 알고자 하는 분들이 실무진에 참여한 연구자들 및 과학자들과 직접 접촉할 수 있도록 그들의 직책과 현재의 소속을 밝혔으며 이 안내서에 사용된 문허 270개 참고문헌 전체를 소개한다.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.2
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• pp.377-398
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• 1999

Calcium fluoride, created by topical fluoride application, is the reservoir for fluoride ion regulated by pH in the oral environment. Therefore, the amount and the maintenance of calcium fluoride have an important role in preventing dental caries. The aim of this study is to evaluate the effect of Nd:YAG laser irradiation on the generation of calcium fluoride and the acid resistance of tooth enamel. The bovine anterior permanent teeth were prepared (n=276), and divided into following groups : no treatment (control) fluoride application alone, laser irradiation alone, laser irradiation after fluoride application, and fluoride application after laser irradiation. And each group was subdivided based on the application time of 1.23% acidulated phosphate fluoride (APF) (5 min and 30 min) and the irradiation energy of Nd:YAG laser ($20J/cm^2\;and\;40J/cm^2$). In case of fluoride application, each group was divided according to KOH treatment. Twenty three treatment conditions were made for this experiment and twelve specimens were assigned to each treatment condition. In each treatment condition, ten specimens were used for chemical analysis and two specimens were observed under SEM. In groups without treating KOH, fluoride content and the depth of enamel dissolved were measured using enamel biopsy technique. In groups with treating KOH, the amount of calcium fluoride was measured by the treatment with 1 M KOH for 24 hours and enamel biopsy was performed after KOH treatment. The results were analyzed by the fluoride content and the depth of enamel dissolved by enamel biopsy, amount and thickness of calcium fluoride, and the surface structures of enamel. The results are as follows: 1. In groups without treating KOH, the fluoride content of removed enamel showed a positive relationship with the energy density of laser when the laser irradiated before fluoride application 2. In groups without treating KOH, the depth of enamel dissolved decreased more with the combined laser and fluoride treatment than with laser or fluoride treatment, except for the case of $20J/cm^2$ laser irradiation after 5 minute fluoride application (p<0.05). 3. The amount of calcium fluoride did not increased by laser treatment with no statistical significance(p>0.05). 4. The particle size of calcium fluoride increased in case of fluoride treatment after laser irradiation, compared with fluoride application alone. In case of laser treatment after fluoride application, the particle size of calcium fluoride increased and some of the particles fused as well. 5. There were no significant differences in the fluoride content of dissolved enamel between groups without treating KOH and control group, except for the case of laser irradiation after treatment of APF for 30 minutes (p>0.05). 6. In groups with treating KOH, depth of removed enamel in the groups of combined treatment with laser and fluoride was shallower than that in fluoride application groups (p<0.05). 7. In groups without treating KOH, the relationship between fluoride content and the depth of enamel dissolved showed more negative (Spearman correlation coefficient: -0.6281) than in groups with treating KOH (Spearman correlation coefficient: -0.3792). The greater amount of calcium fluoride could be found in case where there was a significant differences of the depth of enamel dissolved between groups with and without treating KOH. From these results, it can be concluded that laser seems to be a little effects on the amount of calcium fluoride formation, but has some effect on the lowering the solubility of calcium fluoride. As the combined treatment of laser and fluoride application showed more effective acid-resistant property, more extended recall period for fluoride application can be achieved with this combined treatment in the clinic.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.4
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• pp.662-670
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• 2008

The purpose of this in vitro study was to evaluate the effect of fluoride containing adhesive film on prevention of enamel demineralization. Eighty bovine enamel blocks were divided randomly into 4 groups of 25: (1) APF gel applied ; (2) CavityShield$^{TM}$ applied; (3) 3% fluoride film applied; (4) 5% fluoride film applied; Early caries lesions were produced by placing each specimen into demineralization solution at pH 4.0 for 72 hours. Then lesion of the surface microhardness were measured by the Vicke's hardness test and the lesions depth were measured by polarizing light microscope. The results of the present study are as follows: 1. Difference of microhardness value ($M{\pm}SD$) between control and experimental side was the highest in group II, followed by group IV, III, I but, no significant difference was between group II, III and IV. 2. Difference of mean lesion depth ($M{\pm}SD$) between control and experimental side was the highest in group II, followed by group III, IV and I but no significant difference was between group III and IV. The results of the present study indicate that the fluoride film application is more effective than APF gel and is similar to fluoride varnish application for prevention of dental caries.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.4
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• pp.624-629
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• 2004

The purpose of study was to observe the effect of fluoride and calcium on enamel remineralizaton in vitro. Human premolar enamel specimens were prepared by demineralization in $0.1{\sim}l.0%$ citric acid for 60 minutes. They were remineralized for 6 hours in one of the 1311owing solutions : (1) artificial saliva, (2) artificial saliva with 100ppmF, (3) artificial saliva with 1000ppmF, (4) artificial saliva with 1000ppmCa, and (5) artificial saliva with 100ppmF and 1000ppmCa. No significant remineralization was occurred in artificial saliva and artificial saliva with 100ppmF. Significant remineralization was observed in artificial saliva with 1000ppmF at 3 hours, and in artificial saliva with 1000ppmCa and artificial saliva with 100ppmF and 1000ppmCa at 3 and 6 hours(P<0.05). The remineralization effect of artificial saliva with 100ppmF and 1000ppmCa was greater than that of artificial saliva or artificial saliva with 100ppmF. Addition of F to 100ppm or 1000ppm, addition of Ca to 1000ppm, and increasing the concentration of F from 100ppm to 1000ppm did not significantly increase the remineralization.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.4
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• pp.705-713
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• 2004

The objectives of this study were to evaluate the fluoride release and the change of surface roughness of fluoride releasing restorative materials after toothbrush-dentifrice abrasion. Seven commercially available fluoride releasing restorative materials (Fuji II LC Improved: FL, Compoglass F: CG, Dyract AP: DR, F2000: FT, Ariston: AT, Tetric: TR, and Gradia: GD) were selected as experimental materials. The results obtained were summarized as follows: 1. The AT, FL, and CF groups produce an initially large burst of fluoride release and comparatively low but continuous release of fluoride. But other groups produce no initial burst of fluoride and levels of release remain relatively constant. 2. The rate of fluoride release remains steady state after 40 days. The results of Tukey's test (P<.05), the fluoride release showed the order of decreasing rank as follows: AT > FL > compomers > TC and GD. 3. The surface roughness indicated that the highest value was observed in the FT group and the lowest value was observed in the CF group. The surface roughness of Tukey's test showed the significant differences between groups of FT, AT and FL and groups of CF, DR, GD and TC (P<0.05).

• Resources Recycling
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• v.16 no.4
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• pp.27-32
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• 2007

The characteristics of fluorine removal from wastewater have been investigated by precipitation method using calcium as a precipitant for the purpose of the reuse of treated wastewater. In the conditions of 10 mM of the initial concentration of fluorine and pH 4, the precipitation of fluorine was rapidly progressed within a few minutes after the precipitant was added and the precipitation of fluorine was observed to follow a second order reaction. Also, as the addition of precipitant was increased, the reaction rate constant of fluorine precipitation was found to rise. Postulating that the maximum fluorine removal was attained at pH 4, about 70% of fluorine was precipitated compared with the maximum removal when 10 times of equivalent amount of calcium was employed at pH 2 and the fluorine removal was about 96% compared with its maximum value at pH 3 under the same addition of precipitant. The fluorine precipitation reaction was found to be endothermic and the coexistence of $SiF_6{^{2-}}$ with fluorine resulted in its less removal. Finally, the isoelectric point of the precipitate was examined to be ca. pH 5.

• Journal of Korean society of Dental Hygiene
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• v.22 no.4
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• pp.231-240
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• 2022

Objectives: This study was conducted to survey the currently available fluoride-containing oral hygiene products in Korea to provide consumers with information regarding the concentration and form of fluoride in each product, as well as to determine whether the information was easy to understand. Methods: A total of 64 types of domestic commercial oral hygiene products were purchased from an offline market and evaluated. Results: The domestic commercial toothpaste products contained fluoride in the form of sodium fluoride (NaF) and sodium monofluorophosphate (SMFP). In this study, toothpaste containing 1,000 ppm fluoride compounds accounted for the largest proportion (61.5%). Toothpastes containing below 1,000 ppm fluoride accounted for 34.6%, while toothpastes with fluoride above 1,000 ppm fluoride accounted for 3.9%. Toothpaste containing more than 1,000 ppm fluoride has not been popularized domestically. Mouthwash products contained fluoride compounds at less than 300 ppm concentration. Of the five types of mouthwash products, only two types had labels indicating fluoride concentration. In addition, the location of the labels indicating fluoride concentration differed between manufacturers and even within the same manufacturer. Conclusions: It is important to popularize toothpaste with fluoride levels above 1,000 ppm so that a broader selection of toothpaste can be offered to consumers in need. Standardized information needs to be provided for consumer convenience to aid in choosing appropriate oral hygiene products.

• Elastomers and Composites
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• v.30 no.4
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• pp.263-268
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• 1995

극심한 내열, 내화학성이 요구되는 곳에 사용하는 불소고무는 최적의 불소고무를 선택하고 배합비율을 조절함으로써 사용용도별로 요구되는 특수한 물리화학적 특성뿐만 아니라 여러 가지 성형방법에 따른 공정상의 요구조건을 만족시킬 수 있다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.4
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• pp.2027-2036
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• 2013

Comparison of removal performance between reverse osmosis(RO), nanofiltration(NF), electrocoagulation(EC) and electroadsorption(EA) for removal of nitrate and fluoride often exceeded the limits of water quality in small water treatment plants. Removals of nitrate and fluoride were 72-92% and 74-85% in RO, 5-15% and 1% in NF, 99% and 44% in EA equipped with MWCNT coated electrodes, 82% and 77% in EA equipped with Cu-MWCNT electrodes, and 11-46% and 69-99% in EC. Consequently, high removals of both ions were anticipated in RO. Effective removal of both ions are possible for EC, but great production of sludge is a big burden. EA equipped with the MWCNT electrodes showed a great fluctuation in removal efficiency, and electrode stability should be upgraded.