• Restorative Dentistry and Endodontics
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• 제16권1호
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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.

• 대한화학회지
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• 제7권3호
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• pp.189-196
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• 1963

<디메칠호롬아마이드> 溶媒系에서 有機含할로겐化合物을 弗化加里와 反應시켜 본 結果 $CF_3COOH,\;C_3F_7COOH,\;C_2F_5COOH$와 같은 含弗素有機酸에서는 脫炭酸反應이 일어나며, 含鹽素有機酸, $CH_2ClCOOH,\; CH_3CHClCOOH,\;CHCl_2COOH $및 $o-Cl-C_6H_4COOH$은 一部 弗化反應이 일어나고 雙合(dimerization) 反應이 隨伴된다는 것을 究明하였다. 芳香族할라이드類에서는 反應度를 나타내지 않았으나 芳香環에 誘電子置換基가 두個있는 試藥에서는 主로 雙合反應을 일으켰다. 알콜 및 에스테르類는 通常的인 弗化反應을 잘 일으켰다. 같은 反應을 溶媒 使用치 않고 高溫에서 進行시켜 본 結果 雙合反應物의 收率을 增加시켰고 $o-ClC_6H_4COOH$에서는 環化物(fluorenone)을 少量生成하였다. 反應段階中의 各 試藥의 消耗및 生成에 對한 化學量的關系를 比較檢討한 結果 酸의 反應에서는 普通 脫炭酸反應보다 弗化反應이 優先 進行됨을 究明하였다. 弗化加里의 反應觸發作用및 反應機構에 關하여서는 論議하였다.

• 대한금속재료학회지
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• 제48권3호
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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.

• 대한소아치과학회지
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• 제51권1호
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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.

• 대한방사성의약품학회지
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• 제2권1호
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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.

• 대한화학회지
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• 제13권1호
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• pp.68-74
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• 1969

${\alpha},{\beta$}-dichloro-${\beta$}-phenyl propionate, Ethyl ${\alpha},{\beta$}-dibromo-${\beta$}-phenyl propionate, Etyyl ${\alpha},{\beta$}-dichloro-${\beta$}-(p-chlorophenyl)propionate, 및 dibromo-styrene 等의 化合物을 各種溶媒(dimethly formamide, diethylene glycol, 및 diethylene glyco monomethyl ether 等) 存在下에서 弗化反應을 시켜 보았으며 放射性弗素-18을 追跡子로 使用하여서 위의 化合物들의 弗化카리에 對한 反應度를 檢査하여 보았다. 一般的으로 弗化反應 生成物은 모노弗化物과 脫할로겐된 二重結合物을 生成하였다. diethylglycol 存在下에서 高溫反應시킨 條件下에서는 二重結合生成物이 많았고 diethylene glyco-monoethyl ether 存在下에서 低溫反應시킨 條件下에서는 弗化物이 多量生成하였다. 모노弗化物의 合成方式 및 確認方法에 關하여 說明하였으며 本反應의 合成上의 用途($F^{18}$ 標識化合物包含)에 言及하였다.

• 한국표면공학회지
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• 제49권3호
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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.

• 대한화학회지
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• 제8권4호
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• pp.135-141
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• 1964

아밀아이오다이드를 디메칠홀움아마이드 存在下에서 弗化加里와 低溫反應시켜 본 結果 弗化物과 데칸을 生成하였음. ${\alpha}$, ${\beta}$-디크로로-${\beta}$-페닐-푸로피온酸과 같은 多鹽素化物은 ${\alpha}$-크로로스타이렌, 弗化스타이렌 及 弗化酸을 生成하였음. 이 酸의 에칠에스텔은 弗化物을 生成하지 않고 各種 쌍合物의 混合物을 얻었음. 디부롬스타이렌은 부롬스타이렌과 弗化物을 生成하고 沃度를 含有한 有機酸, 메-타요드벤젠익酸은 有機酸의 鹽과 微量의 쌍合物을 生成하였음. 메타요드토류엔 及 1-아미노-4-요-드-2-메칠벤젠과 같은 沃化物은 弗化物은 弗化加里에 對하여 反應을 나타내지 않었음. 本報에는 各 反應條件과 弗化反應, 脫炭酸反應 及 쌍合反應에 關하여 論義하였음.

• Molecules and Cells
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• 제27권2호
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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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• 제24권1호
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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.