Miura H, Araki Y, Ohno H
Department of Preventive Dentistry, School of Dentistry, Higashi-Nippon-Gakuen University, Hokkaido, Japan.
Dent Mater J. 1993 Dec;12(2):209-18. doi: 10.4012/dmj.12.209.
A precipitation reaction between hydroxyapatite (HAp) and fluoride solution was analyzed by computer simulation. The system comprised excess HAp and 0.05-0.2 M acetic buffer solutions containing 0.5-2.0 mM potassium fluoride. The amounts of HAp dissolved and calcium salts precipitated and activities of all the species present in the solution were calculated during the process. In the systems, calcium fluoride was initially precipitated when applying the fluoride solution to HAp, followed by precipitation of fluorapatite (FAp) and re-dissolution of the previously precipitated calcium fluoride at a critical pH at which the ion activity product exceeded the solubility product of FAp. The critical pH was increased with pH of the buffer, whereas it was scarcely affected by fluoride ion concentration, and it was necessary to introduce phosphate ions in advance into the buffer for predominant precipitation of FAp in this system.
通过计算机模拟分析了羟基磷灰石（HAp）与氟化物溶液之间的沉淀反应。该系统包含过量的HAp和含有0.5 - 2.0 mM氟化钾的0.05 - 0.2 M乙酸缓冲溶液。在此过程中计算了溶解的HAp量、沉淀的钙盐量以及溶液中所有物种的活度。在这些系统中，将氟化物溶液施加到HAp上时，最初会沉淀出氟化钙，随后在离子活度积超过氟磷灰石（FAp）溶解度积的临界pH值下，会沉淀出氟磷灰石，并且先前沉淀的氟化钙会重新溶解。临界pH值随缓冲液的pH值升高而增加，而几乎不受氟离子浓度的影响，并且有必要预先将磷酸根离子引入缓冲液中，以便在该系统中主要沉淀出FAp。
