• 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.

• Journal of the Korean Chemical Society
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• v.7 no.3
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• pp.189-196
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• 1963

Reactions between potassium fluoride with organic halogen-containing carboxylic acids in dimethyl formamide solvent gave a decarboxylation reaction for the case of fluoro carboxylic acids of the type of $CF_3\;COOH,\;C_3F_7COOH,\;and\;C_2F_5COOH,$ whereas an additional partial fluorination together with dimerization reaction occurred for the chlorine containing acids of the type of $CH_2ClCOOH,\;CH_3CHClCOOH, \;CHCl_2COOH\;and\;o-Cl-C_6H_4-COOH.$ The phenyl halides showed no reactivity, but the halides with two electron attracting substituents on the benzene ring gave mainly dimerization reaction. The esters and alcohols gave an usual fluorination reaction. The same reactions in absence of the solvent at the elevated temperature increase the yield of the dimerized product and gave the cyclized product, fluorenone, in case of ο-chlorobenzoic acid. It was found that the fluorination usually precede the decarboxylation reaction by checking the stiochemical sequence of reaction. Catalytic influence of potassium fluoride were discussed and the mechanism of the reaction was considered.

• Korean Journal of Metals and Materials
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• v.48 no.3
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• pp.218-224
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• 2010

Direct copper electroplating on Mg alloy AZ31B was carried out in a traditional pyrophosphate copper bath containing potassium fluoride. Electrochemical impedance spectroscopy and polarization methods were used to study the effects of added potassium fluoride on electrochemical behavior. The chemical state of magnesium alloy in the electroplating bath was analyzed by X-ray photoelectron spectroscopy. Adhesion of the copper electroplated layer was also tested. Due to the added potassium fluoride, a magnesium fluoride film was formed in the pyrophosphate copper bath. This fluoride film inhibits dissolution of Mg alloy and enables to electroplate copper directly on it. A dense copper layer was formed on the Mg alloy. Moreover, this copper layer has a good adhesion with Mg alloy substrate.

• Journal of the korean academy of Pediatric Dentistry
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• v.51 no.1
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• pp.80-87
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• 2024

Silver diamine fluoride, which can arrest dental caries, is alkaline and may cause mild soft tissue irritation. Water-based silver fluoride has a neutral pH, which is closer to the physiological range, and is biocompatible for use in the oral environment. This study aimed to evaluate the effect of water-based silver fluoride on remineralizing early enamel lesions by comparing it with other fluoride agents through microhardness and quantitative light-induced fluorescence measurements. An in vitro study with intact bovine incisors was performed. Artificial enamel lesions were induced and subjected to microhardness and quantitative light-induced fluorescence testing. Specimens were randomly divided into 4 groups for treatment. The specimens in group I were treated with water-based silver fluoride and potassium iodide, group II with silver diamine fluoride and potassium iodide, group III with sodium fluoride varnish, and group IV with distilled water. After 8 days of pH cycling, the specimens were subjected to microhardness and quantitative light-induced fluorescence testing. Water-based silver fluoride and silver diamine fluoride showed the greatest increases in microhardness and quantitative light-induced fluorescence, with no significant differences between the two. Sodium fluoride varnish also exhibited a significant increase in microhardness and quantitative light-induced fluorescence, but the differences were smaller than those for water-based silver fluoride and silver diamine fluoride. Water-based silver fluoride is considered useful in a clinical setting for remineralizing enamel lesions, with the advantages of no risk of tissue burn and improved taste and smell.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.2 no.1
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• pp.17-21
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• 2016

Alkali metal fluoride sources (MFs) such as potassium fluoride (KF) have been widely used as a fluoride source in the nucleophilic displacement reaction. However, they have low solubility and nucleophilicity in most of the organic solvents. Bulky fluoride sources such as tetrabutylammonium fluoride (TBAF) were substituted for MFs to improve these properties. However, hygroscopic property of TBAF makes it less convenient for handling as well as its strong basic property can make the side-reaction occur. Recently, novel fluoride sources have been developed to solve these problems. In this paper, we would like to introduce coordinated fluoride sources as a new fluoride sources such as tetrabutylammonium tetra(t-butyl alcohol)-coordinated fluoride, crown ether metal complex fluoride, and various bulky alcohols coordinated fluoride complexes. In particular, bulky alcohol coordinated fluoride source could generated by the controlled hydrogen-bonded of fluoride with alcohols and these fluoride sources have better stability and reactivity with showing low hygroscopic property. The study of these fluoride sources will help to understand the characteristic of [$^{18}F$]fluoride for increasing the radiochemical yield in the [$^{18}F$]radiofluorination.

• Journal of the Korean Chemical Society
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• v.13 no.1
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• pp.68-74
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• 1969

Flourination of Ethyl, ${\alpha},{\beta$}-dichloro-${\beta$}-phenyl propionate, Ethyl ${\alpha},{\beta$}-dibromo ${\beta$}-phenyl propionate, Ethyl ${\alpha},{\beta$}-dichloro ${\beta$}-(p-chloro-phenyl) propionate, and dibromostyrene by potassium fluoride were investigated in presence of dimethyl formamide, diethylene glycol, and diethylene glycol monomethyl-ether. The reactivity of these organic halogen esters and hydrocarbons towards potassium fluoride was checked further by means of radioactive fluorine-18. tracer. Generally, the reaction gave monofluoride together with dehalogenated olefin. The formation of olefine was increased when the reaction was done at high reaction temperature in presence of diethylene glycol, whereas the lower reaction temperature in presence of diethyleneglycol monomethyl ether favored the formation of mono fluoride in a good yield. The procedures and methods of the identification of monofluorides were described and the feasibility of this reaction of fluorine containing ester including the F-18 labelled compounds was discussed.

• Journal of the Korean institute of surface engineering
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• v.49 no.3
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• pp.280-285
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• 2016

In this study, we investigated the influences of potassium fluoride(KF) addition on the surface characteristics of plasma electrolytic oxidation(PEO) coating produced on Al alloy. The PEO of marine grade Al alloy(5083 grade) was conducted in KOH 1g/L solution adding different concentrations of KF(0, 1 and 2 g/L) under a galvanostatic regime. With KF addition, unusual behavior was observed on the voltage-time characteristic curves, which can be characterized by the following process: (i) initial rapid increase in voltage (ii) a short plateau after 1st breakdown (iii) gradual increase in voltage (iv) intermittent fluctuation of voltage after 2nd breakdown. The SEM observation revealed irregular surface morphology with KF addition, as compared with one formed without KF addition, which had a reticulate structure. The XRD analysis detected the formation of aluminium hydroxide fluoride hydrate($H_{4.76}Al_2F_{3.24}O_{3.76}$) on surface grown by PEO process with KF. Particularly, at very early stage of the process (~ 120 s), thin film was formed having nanoporous structure, and F element was confirmed on surface by EDS analysis. The thickness and surface roughness of the coating increased with increasing KF concentration. As a result, KF addition was found to be less beneficial influences on PEO of marine grade Al alloy, and therefore needs further research to improve its capability.

• Journal of the Korean Chemical Society
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• v.8 no.4
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• pp.135-141
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• 1964

The reaction of potassium fluoride with amyl iodide in presence of dimethylformamide at low temperature gave a fluorination product together with decane. Polyhalogenated acid such as ${\alpha}$, ${\beta}$,-dichloro-${\beta}$-phenyl-propionic acid gave ${\alpha}$-chlorostyrene, fluorinated styrene, and fluorinated acid. The same reaction with the ethyl ester did not give the fluorination product and gave a mixture of various dimerized product. Dibromostyrene gave bromostyrene together with fluorination product. Iodo acid such as m-iodo acid gave the salt and a trace quantity of dimerized product. Iodides such as m-iodotoluene and 1-amino-4-iodo-2-methyl benzene did not show any appreciable reactivity towards potassim fluoride. The reaction condition was described, and fluorination, ${\alpa}$-dehydrofluorination, decarboxylation, and dimerization were discussed.

• Molecules and Cells
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• v.27 no.2
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• pp.191-198
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• 2009

The present study was undertaken to determine whether treatment with genistein, the plant-derived estrogen-like compound influences agonist-induced vascular smooth muscle contraction and, if so, to investigate related mechanisms. The measurement of isometric contractions using a computerized data acquisition system was combined with molecular experiments. Genistein completely inhibited KCl-, phorbol ester-, phenylephrine-, fluoride- and thromboxane $A_2$-induced contractions. An inactive analogue, daidzein, completely inhibited only fluoride-induced contraction regardless of endothelial function, suggesting some difference between the mechanisms of RhoA/Rho-kinase activators such as fluoride and thromboxane $A_2$. Furthermore, genistein and daidzein each significantly decreased phosphorylation of MYPT1 at Thr855 had been induced by a thromboxane $A_2$ mimetic. Interestingly, iberiotoxin, a blocker of large-conductance calcium-activated potassium channels, did not inhibit the relaxation response to genistein or daidzein in denuded aortic rings precontracted with fluoride. In conclusion, genistein or daidzein elicit similar relaxing responses in fluoride-induced contractions, regardless of tyrosine kinase inhibition or endothelial function, and the relaxation caused by genistein or daidzein was not antagonized by large conductance $K_{Ca}$-channel inhibitors in the denuded muscle. This suggests that the RhoA/Rho-kinase pathway rather than $K^+$- channels are involved in the genistein-induced vasodilation. In addition, based on molecular and physiological results, only one vasoconstrictor fluoride seems to be a full RhoA/Rho-kinase activator; the others are partial activators.

• Journal of Periodontal and Implant Science
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• v.24 no.1
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• pp.196-204
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• 1994

The purpose of this clinical trial was to study the effectiveness of 5% potassium nitrate dentifrice as a daily home treatment of dentinal hypersensitivity. Thirty subjects with dentinal hypersensitivity were included in a 4-week, double-blind, parallel, comparative study. Stimuli used included mechanical, cold water and compressed air blasts. A subjective assessment of the degree of hypersensitivity for each stimulus was recorded. The results indicated that 5% potassium nitrate dentifrice, in comparision with a conventional fluoride dentifrice, reduced dentinal hypersensitivity to a significant degree. The therapeutic response to potassium nitrate was apparent within 2 weeks and increased continuously for the length of the study period. We conclude that 5% potassium nitrate dentifrice is an effective agent for the daily home treatment of dentinal hypersensitivity.