Effect of fluoride on the growth of hydroxyapatite and human dental enamel.
Effect of fluoride on the growth of hydroxyapatite and human dental enamel.
复制标题
氟化物对羟基磷灰石和人牙釉质生长的影响。
作者：
Z. Amjad;G. H. Nancollas
一种高度可重复的种子生长方法已被用于研究磷酸钙在人牙釉质和羟基磷灰石晶种上的矿化，pH值为7.4，温度为37 °C，稳定的过饱和磷酸钙溶液中含有各种浓度的氟离子。的pH值和pF值保持恒定的电位通过添加氢氧化钾和氟化钾，分别和生长的材料进行了表征化学，红外光谱，扫描电子显微镜和随后的溶解动力学实验。低浓度的氟化物（约0.15 ppm）降低了初始阶段的结晶速率，但在较高氟化物浓度（1-5 ppm）的存在下观察到磷酸钙矿化的增强。而第一次形成的表面相的化学计量对应于在不存在氟化物的情况下磷酸八钙的化学计量，在其存在下指示较高的钙/磷酸盐摩尔比。
A highly reproducible seeded growth method has been used to study the mineralization of calcium phosphate on human enamel and hydroxyapatite seed crystals at a pH of 7.4 and at 37 °C in stable supersaturated solutions of calcium phosphate containing various concentrations of fluoride ion. The pH and pF values were maintained constant potentiometrically by the addition of potassium hydroxide and potassium fluoride, respectively, and the grown material was characterized chemically, by infrared spectroscopy, by scanning electron microscopy and by subsequent dissolution kinetic experiments. Low concentrations of fluoride (∼ 0.15 ppm) reduce the rate of crystallization in the initial stages, but an enhancement of calcium phosphate mineralization is observed in the presence of higher fluoride concentrations (1–5 ppm). Whereas the stoichiometry of the first-formed surface phase corresponds to that of octacalcium phosphate in the absence of fluoride, higher molar calcium/phosphate ratios are indicated in its presence.