CALCIUM PHOSPHATE CEMENTS

自硬化磷酸钙骨水泥（CPC），在NIH资助下开发 （DE 05030），已经证明在许多牙科和医疗领域是有用的。 目前可用的材料不能很好地工作的应用。 动物研究的结果表明， CPC的性能可以显著提高水泥的有用性 在临床应用中。 拟议研究的目标是 阐明磷酸钙化合物之间的反应机制， 形成水泥，了解水泥的物理化学和机械性能， 水泥在不同条件下形成。 具体目标是： 1. 为了研究结晶度、溶解度和溶解速率， 近化学计量羟基磷灰石（OHAp）在不同骨水泥中形成 系统和CPC中缓慢或快速硬化。 此外，为了 确定在这些条件下形成的水泥的机械性能 条件 2. 为了研究钙缺乏的程度，结晶度，溶解度， 在具有总Ca/P的骨水泥中形成的OHAp的溶解速率 摩尔比低于1.67，并研究这些材料的力学性能 水泥 3. 为了研究碳酸盐结合的程度和性质， 结晶度，溶解度和溶解速率的OHAp中形成的 不同的水泥系统，并与钠或钾作为 碳酸盐源的阳离子组分。 4. 为了研究含有不同量的水泥的溶解速率， 微孔（孔径小于1 μ m）和微孔（孔径150 2200 μ m）。 从建议中获得的信息应该是有价值的设计 具有特定体外和体内特性的CPC最适合用于 不同类型的临床应用。

Self-hardening calcium phosphate cements (CPC), developed under a NIH grant (DE05030), have proven useful in a number of dental and medical applications for which currently available materials do not work well. Results from animal studies indicated that improvements in several key properties of CPC can significantly increase the usefulness of the cement in clinical applications. The objectives of the proposed research are to elucidate mechanisms of reactions between calcium phosphate compounds that form cements and to understand physicochemical and mechanical properties of the cements formed under different conditions. The specific aims are: 1. To study the crystallinity, solubility, and rate of dissolution of the nearly stoichiometric hydroxyapatite (OHAp) formed in different cement systems and in CPCs that harden slowly or rapidly. Additionally, to determine the mechanical properties of the cements formed under these conditions. 2. To study the degree of Ca-deficiency, crystallinity, solubility, and rate of dissolution of OHAp formed in cements that have an overall Ca/P molar ratio below 1.67, and to study the mechanical properties of these cements. 3. To study the extent and the nature of carbonate incorporation, crystallinity, solubility, and rate of dissolution of OHAp formed in different cement systems and with either sodium or potassium as the cationic component of the carbonate source. 4. To study the rate of dissolution of cements that contain varied amounts of micropores (pore size of lessor 1 mum) and micropores (pore size of 150 2 200 mum). The information obtained from the proposed should be valuable in designing CPCs with specific in vitro and in vivo properties that are best suited for different types of clinical applications.