• The korean journal of orthodontics
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• v.47 no.5
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• pp.306-312
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• 2017

Objective: The purpose of this study was to examine the effect of commercially available fluoride-containing oral rinses on the corrosion behavior of titanium alloys, which are the main components of orthodontic miniscrews. Methods: Four commercially available oral rinses (solution A, pH 4.46/260 ppm fluoride; solution B, pH 4.41/178 ppm fluoride; solution C, pH 6.30/117 ppm fluoride; and solution D, pH 4.17/3.92 ppm fluoride) were tested on titanium alloy (Ti-6Al-4V) circular plates, and saline was used as the control. The open-circuit potential and potentiodynamic polarization of these materials were measured. Thereafter, all samples were evaluated under a field-emission scanning electron microscope. Results: Among the tested oral rinses, except solution D, the more the fluoride content was, the greater was the corrosion potential downtrend; the corrosion resistance of the titanium alloy sample was also lowered significantly (p < 0.05). Field-emission scanning electron microscopic analysis of the surface morphology of the titanium alloy samples revealed that all samples had some defects, crevices, or pitting after exposure to the oral rinses than before treatment. In particular, the samples in solution A showed the most changes. Conclusions: Commercially available oral rinses having a high fluoride concentration and a low pH may reduce the corrosion resistance of titanium alloys used in dental appliances such as orthodontic titanium miniscrews and brackets.

• Restorative Dentistry and Endodontics
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• v.18 no.1
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• pp.27-37
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• 1993

The purpose of this study was to determine the fluroide release levels of new fluoride-containing liner/base cements and the fluoride uptake by dentin surfaces. Ten specimens of each brand (Fuji ionomer Type III, Fuji Lining LC, Timeline, Vitrebond and XR ionomer) were made, polymerized and placed in fluoride-free distilled water at $37^{\circ}C$, 100% relative humidity for 24 hours. The extracting solution of specimen was exchanged and fluoride release was measured daily for the 30 days. For fluoride uptake study, twenty-five extracted human lower molars were sectioned longitudinally in the mesiodistal direction with a diamond disc. Five teeth were filled with each material and then stored at $37^{\circ}C$, 100% humidity for 4 weeks. Fluoride uptake by dentin from the test materials was evaluated using electron probe micro X-ray analyzer. The following results were obtained : 1. The amounts of fluoride release showed no significant difference between Fuji ionomer Type III and Fuji Lining LC, but showed significant difference between other groups. XR ionomer released significantly greater fluoride than any other group(P<.001). 2. All the materials have a burst effect which more fluoride released in then first 3 day and showed significant decrease over the test period (P<0.001). 3. XR ionomer group showed fluoride penetration to approximately $50{\mu}m$ deep in dentin. But other material groups showed very little fluoride uptake by dentin.

• Restorative Dentistry and Endodontics
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• v.16 no.1
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• pp.216-225
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• 1991

The purpose of this study was to evaluate the desensitizing effect of potassium oxalate(Group I), sodium fluoride (Group II), and control group (Group III). The 120 teeth of 26 patients who had been complained dentinal hypersensitivity were divided into three groups by applicating agent. The observation was done before and immediately after treatment. The data were statistically analyzed and the results were as followed. 1. Potassium oxalate showed the best desensitizing effect to the stimuli, followed by sodium fluoride, control group, and there was a significant difference (p<0.05) in desensitizing effect among the groups. 2. Potassium oxalate showed the best desensitizing effect to the stimuli, followed by sodium fluride, control group on both cervical abrasion and gingival recession, and there was a significant difference (p<0.05) in desensitizing effect among the groups on both cervical abrasion and gingival recession. 3. There was no significant difference (p<0.05) in effect of the desensitization between cervical abrasion and gingival recession. 4. The scratch and air blast I were more effective in desensitiziation than other stimuli with significant difference (p<0.05). In view of the results mentioned above, it can be conceived that potassium oxalate is more effective than sodium fluoride on the reduction of dentinal hypersensitivity.

• The korean journal of orthodontics
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• v.2 no.1
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• pp.23-28
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• 1971

In this study, sections of twenty eight teeth were used to investigate the effect of topical application of $8\%$ stannous fluoride on the decalcification rate of enamel surfaces stripped in a manner suggested for orthodontic purpose. The enamel treated with a single application of a fluoride had a significantly lower tile rate of decalcification for the first 96 hours to lactate buffer solution. After double application of fluoride, decalcification rate decreased signicantly. This study suggested that the continuing protection of stripped surfaces should be sought by regularly scheduled treatment of the enamel with the topical application of fluoride and regular use of a fluoride containing dentifrice.

• The Journal of the Korean dental association
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• v.48 no.6
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• pp.454-458
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• 2010

Dental caries is one of the most common chronic diseases in the world, which are caused by complex actions of oral such factors as the bacteria, food, tooth, saliva and other factors. Although this is one of the typical oral diseases, we can acquire a high prophylactic effect by use of proper prophylactic measures and management. At the beginning of the 1940s, fluorine was first introduced to prevent dental caries which now is widely used. The fluorine application effects are varied from different concentrations and categories of fluorine, and different application method and frequency, etc. There is great debate on the best application method at the present. Dental clinics use iontophoresis as the application method and use it clinically. It uses APF (1.23%, Acidulated phosphate fluoride, APF) and uses 2% NaF so as to encourage more absorption of fluorine. Recently, fluoride varnish, which uses admixture mucus of colophony resin into 5% NaF, and a variety of forms that can be applied in the oral cavity are still being continuously researched. When using fluoride topical application on the enamel surface, it was highly recommended that fluoride varnish be used directly after fluoride iontophoresis rather than fluoride iontophoresis only or fluoride varnish by itself. The new method is more effective and does not need repeated application.

• Journal of Korean society of Dental Hygiene
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• v.10 no.3
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• pp.473-481
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• 2010

Objectives : To evaluate the effect of fluoride application on the color and microhardness of bleached enamel and compare it to that of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) application. Methods : Twenty freshly extracted human adult molar were each sectioned into halves, the specimens divided and treated according to five experimental groups: Group 1, treatment with 10% carbamide peroxide (CP) bleaching agent; Group 2, treatment with 10% CP followed by a 1.23% fluoride gel application; Group 3, treatment with 10% CP followed by a 2.23% sodium fluoride varnish application; Group 4, treatment with 10% CP followed by a 0.11% sodium fluoride gel application; Group 5, treatment with 10% CP followed by a CPP-ACP gel application. All groups were treated 6 h per day for 14 days then immersed in distilled water for 2 weeks. Changes in enamel color were evaluated on Baseline and Day 14. Microhardness were evaluated on Baseline, Days 7 and 14. Statistical analysis was performed using one-way ANOVA and post-hoc Tukey tests. Results : All the bleached enamel specimens revealed increased whiteness and overall color value. Group 1 showed the lowest microhardness values than that of Groups 2, 3, 4 and 5. In all groups, the hardness of tooth after bleaching showed a significant decrease in the microhardness as compared with the one prior to tooth bleaching. The specimens treated with remineralizing agents showed relatively less reduction in enamel microhardness than control group. Conclusions : The addition of fluoride and CPP-ACP did not impede the whitening effect. The use of remineralizing agents during bleaching treatment can significantly enhance the microhardness of bleached enamel.

• Restorative Dentistry and Endodontics
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• v.24 no.2
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• pp.330-336
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• 1999

In biological systems, the mineral that forms hard tissue is of an apatitic nature, and hydroxyapatite($Ca_5OH(PO_4)_3$: HA) is generally considered as the prototype for such a mineral. Thus, the precipitation of HA, having biological implications, has been the subject of several investigations. Crystal growth studies using HA seeds in supersaturated solutions have enhanced our understanding of the process and mechanism involved in seeded crystal growth. From these studies, it has become apparent that the precipitation rate of HA onto the seed crystals depends on the various conditions, especially on the additives. The relation between the supersaturated solution containing fluoride and the process of HA crystal growth enhances the understanding of mechanism of HA crystal growth. Until recently, the studies have been on the crystal growth of enamel minerals and synthetic HA seeds in the supersaturated solution containing 1~2 ppm fluoride. The purpose of the present investigation is to study the effect that fluoride of high concentration has on the crystal growth kinetics of HA. In order to produce the composition found in the secretory enamel fluid, experimental solutions of 1mM Ca, 3mM P, and 100mM Tris as background electrolyte were used. Then this experimental solutions were added to 0, 2, 4, 6, 8, 10 ppm fluoride. The effect of fluoride at high concentrations on the precipitation was examined in a bench-top crystal growth model adopting a miniaturized reaction column. Chemical analysis was employed for characterization of working solutions before and after the experimentation. Remarkable findings were : 1) the amount of crystal growth was gradually accelerated as the fluoride concentration increased until 6 ppm, but decreased in 8 and 10 ppm fluoride; 2) the amount of fluoride ion consumed in crystal formation was constant despite the increase in fluoride concentration.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.2
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• pp.405-421
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• 1997

The main purpose of this study was to evaluate the acid resistance and antimicrobial effect of fluoride-laser combined application. Recently extracted third molars were used. $5{\times}3mm$ of the buccal and lingual specimens were exposed and incipient artificial carious lesions were formed by keeping them in the artificial cariogenic solution for 5 days. They were divided into five groups and treated with fluoride and laser according to the predetermined regimen. The acid resistance was compared between groups by chemical quantitative analysis of the calcium and phosphorous released into the test solution after single or combined application of fluoride and laser. The antimicrobial effect of each group was analyzed by counting the number of colony forming units after microbial incubation. The results from the present study can be summarized as follows; 1. Experimental groups showed lower values in calcium and phosphorous contents as well as in $CFU/m{\ell}$(colony forming units) than control group. Combined application groups showed lower values than single application groups. 2. Acid resistance and antimicrobial effect by fluoride and laser treatment were confirmed in this study. 3. Based upon the above-mentioned results of this study, it can be assumed that the use of laser-fluoride combined application may provide the child and adolescent patient population with antimicrobial effect as well as acid resistance. Further studies using various materials and experimental conditions are being encouraged.

• The Korean Journal of Pharmacology
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• v.8 no.2
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• pp.41-47
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• 1972

Fluorides were supposed to exert a stimulatory action on the catecholamine release. In this study, the authors attempted to investigate the action of sodium fluoride on the catecholamine release from the isolated perfused cow adrenal gland and rat heart. And also the inhibitory effect of sodium fluoride on the monoamine oxidase activity in rat heart and liver mitochondria was investigated. The monoamine oxidase activity was measured by the conversion of benzylamine to benzaldehyde. The results obtained were follows; 1. Sodium fluoride stimulated the release of catecholamine from the isolated perfused cow adrenal gland and rat heart. 2. Sodium fluoride inhibited the rat heart and liver mitochondrial monoamine oxidase activity.

• Journal of Korean Society of Water and Wastewater
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• v.17 no.4
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• pp.510-518
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• 2003

The fluoride work management of water supply conveyance has been recommending by the WHO to prevent of tooth decay. Fluoridation of public water supplies has been practiced since 1945. The present approximately 67 countries reported community water fluoridation benefiting many cities. At our country, Fluoridation began in 1981 in Chongiu and Jinhea. In 2002, approximately 40 cities have large populations consuming fluoridated water. But Chongiu stopped fluoridation water works. Few public health measures have been accorded greater clinical and laboratory research, epidemiological study, clinical trials, and public attention than has water fluoridation. In this study, chemical analysis of Sodium Silicofluoride and Fluoride Feed Equipment analyzed. And this study proposed to Fluoride concentration experimental (lab. and field exp.), economics analysis, prevention effect. This study can be decided on the concentration of fluoride injection in Water Fluoridation. Hereafter, this study will be useful in safety and economics of Water Fluoridation in the future.