Featherstone J D, Glena R, Shariati M, Shields C P
Department of Oral Biology, Eastman Dental Center, Rochester, New York 14620.
J Dent Res. 1990 Feb;69 Spec No:620-5; discussion 634-6. doi: 10.1177/00220345900690S121.
The anti-caries activity of fluoride is contributed to in several ways. Two major aspects of fluoride action are (i) the inhibition of demineralization at the crystal surfaces within the tooth, and (ii) the enhancement of subsurface remineralization resulting in arrestment or reversal of caries lesions. Fluoride present in the aqueous phase at the apatite crystal surface may play a determining role in the inhibition of enamel or dentin demineralization. In one part of the present study, the initial dissolution rate of synthetic carbonated-apatite in acetate buffers was measured with fluoride present in the buffer in the 0-2.6 mmol/L (0-50 ppm) range. Inhibition of demineralization was shown to be a logarithmic function of the fluoride concentration in solution. In the second part of the present study, an in vitro pH-cycling model was used for determination of the effect on net de/remineralization of enamel by treatment solutions containing fluoride in the 0-26 mmol/L (0-500 ppm) range. The net mineral loss was shown to be negatively related to the logarithm of the fluoride concentration. These studies have demonstrated an exponential quantitative relationship between fluoride concentration and inhibition of apatite demineralization or enhancement of remineralization. The clinical implications are (i) that simply increasing fluoride concentration may not necessarily give increased cariostatic benefit, and (ii) that improving the means of delivery of relatively low fluoride concentrations for longer times should be more appropriate for enhancing clinical efficacy.
氟化物的防龋活性通过多种方式实现。氟化物作用的两个主要方面是：（i）抑制牙齿内部晶体表面的脱矿作用；（ii）增强牙本质表层再矿化作用，从而阻止龋损进展或使其逆转。磷灰石晶体表面水相中存在的氟化物可能在抑制牙釉质或牙本质脱矿方面起决定性作用。在本研究的一部分中，测定了合成碳酸磷灰石在醋酸盐缓冲液中的初始溶解速率，缓冲液中氟化物浓度范围为0 - 2.6 mmol/L（0 - 50 ppm）。结果表明，脱矿抑制作用是溶液中氟化物浓度的对数函数。在本研究的第二部分中，使用体外pH循环模型来测定含氟浓度范围为0 - 26 mmol/L（0 - 500 ppm）的处理溶液对牙釉质净脱矿/再矿化的影响。结果表明，净矿物质损失与氟化物浓度的对数呈负相关。这些研究证明了氟化物浓度与磷灰石脱矿抑制或再矿化增强之间存在指数定量关系。其临床意义在于：（i）单纯提高氟化物浓度不一定能增加防龋效果；（ii）延长相对低浓度氟化物的输送时间可能更有利于提高临床疗效。
