QUANTITATION OF ENAMEL DEMINERALIZATION MECHANISMS

描述：此应用程序的长期目标是获得 更好地了解龋齿的发生机制，并提供 为改进治疗方案的预防措施提供合理依据。这个 申请者建议进行脱矿基础研究 碳酸化磷灰石(CAP)和人牙釉质(HE)的动力学 总的目标是确定脱矿依赖于 关于矿物相组成和外相组成的问题 溶解介质。特别是，亚稳态的概念 平衡溶解度(MES)将用于研究CAP和HE在 各种合成条件和溶解条件。温度 预处理也将用作探针，它与矿物一起 相变量应提供以下两方面的基本信息 结构有序性和溶解性发生变化。这一信息可能表明 激光照射可能通过其作用机制来减少 人牙釉质对酸侵蚀的敏感性。申请人已证明 CAP和HE具有表观溶解度(MES)分布。MES 分布已经被证明控制了两种初始溶出速率 以及长达8天的亚稳平衡。解体驱动力 力由一种不涉及碳酸盐的表面络合物来支配， 尽管驱动力的大小取决于内部 矿物的碳酸盐含量及其相关的结晶度。 具体目标是1)检查MES的适用范围 以及表面复数假设，重点是使用 CAP制剂的组成和结晶度作为独立的 变量；以及2)检验温度处理在 HE和CAP的200-500摄氏度范围可引起 结构有序，导致溶解度(MES)和 这些影响取决于结晶度和/或碳酸盐 内容。评估方法包括化学分析、红外光谱 光谱学、X射线衍射、BET表面分析、透射率 电子显微镜、MES测定和初始溶出度 将利用费率确定。随着研究的进展， 信息将汇集在一起，为 CAP，HE，也许在更广泛的意义上，人牙本质或 骨矿物质。

DESCRIPTION: The long-term objectives of this application are to gain a better understanding of the mechanisms of dental caries and to provide rational bases for improved preventive of therapeutic regimens. The applicant proposes to conduct basic studies of the demineralization kinetics of carbonated apatites (CAP's) and human dental enamel (HE) with a general objective of establishing how demineralization depends on the composition of both the mineral phase and the external dissolution medium. In particular, the concept of metastable equilibrium solubilities (MES) will be used to study CAP and HE under a variety of synthesis conditions and solution conditions. Temperature pretreatment will also be used as a probe, which, together with mineral phase variables, should provide both fundamental information on structural order and solubility changes. This information may suggest possible mechanisms by which laser irradiation might act in reducing the susceptibility of human enamel to acid attack. The applicant has shown that CAP and HE have a distribution of apparent solubilities (MES). MES distributions have been shown to govern both initial dissolution rates and metastable equilibrium for up to 8 days. The dissolution driving force is governed by a surface complex that does not involve carbonate, although the magnitude of the driving force depends on the internal carbonate content of the mineral and its related crystallinity. The specific aims are 1) to examine the range of applicability of the MES and of the surface complex hypothesis with emphasis on employing composition and crystallinity of the CAP preparations as the independent variables; and 2) to test the hypothesis that temperature treatments in the range of 200-500 C of HE and CAP can cause abrupt changes in structural order, resulting in abrupt changes in solubility (MES) and that these effects are dependent on crystallinity and/or carbonate content. Assessment methods including chemical analysis, IR spectroscopy, X-ray diffraction, BET surface analysis, transmission electron microscopy (TEM), MES determinations, and initial dissolution rate determinations will be utilized. As the study progresses, information will be brought together to provide a basic rationale for the behavior of CAP, HE and perhaps in the broader sense, human dentin or bone mineral.