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S Thiradilok

Publications and source records attributed to S Thiradilok.

8 recordsLinked to original sources
PubMed1979

Effects of magnesium and fluoride on ion exchange and acid resistance of enamel.

Labial surfaces of bovine incisor enamel, after weak acid demineralization, were exposed for 24 h in solutions that contained trace levels of calcium as 45Ca, 0.4 mM NaF, and 1.0 mM MgCl2 at pH 7.0. The solutions approached saturation with apatites in the absence of NaF, and saturation with fluorapatites in the presence of NaF. NaF greatly increased the exchange of 45Ca. MgCl2 decreased 45Ca exchange, but had no effect on F- exchange in the surface minerals. MgCl2 decreased, while NaF increased the acid resistance of the exchanged surface minerals on later exposure to 10 mM acetic acid at pH 4.5. These results indicated that magnesium in oral fluids and tooth minerals may promote caries.

Acetates↗
PubMed1977

Effects of bicarbonate on remineralization of enamel.

Enamel surfaces were demineralized in acetic acid and remineralized in solutions that contained 1.5 mM calcium, 1.0 mM phosphate, and 0.0, 5, 15, and 25 mM NaHCO3, and 0.00 or 5.0 mM Naf at pH 7.0. NaF in CO2-free solutions increased the rates of calcium and phosphate uptake during remineralization. Bicarbonate in NaF-free solutions caused small increases of calcium and phosphate uptake. Bicarbonate with NaF in solutions synergistically increased calcium uptake, but did not affect phosphate uptake. Bicarbonate reduced fluoride uptake by about 50% during remineralization, and increased the Ca/P ratios of deposited minerals from about 1 (dicalcium phosphate) to approach and exceed the ratios of apatites.

Animals↗
PubMed1977

The carbonate and fluoride in surfaces of remineralized enamel.

Analyses were made of samples of surface enamel collected before and after acid demineralization and after subsequent remineralization in solutions containing calcium and phosphate and various levels of bicarbonate and fluoride ions. Demineralization caused a preferential loss of carbonates. Remineralization was increased by both fluoride and bicarbonate ions. With no bicarbonate in the calcifying solution, 0.25 to 4.0 mM NaF increased mineral formation and thereby caused a relative reduction of its carbonate content. With 0.5 mM NaF (10 ppm F-) and 5, 15, and 25 mM HCO-3 in remineralizing solutions more carbonate was deposited than in the absence of NaF. Five and 15 mM HCO-3 increased, but 25 mM HCO-3 decreased, deposit of fluoride in enamel.

Acetates↗