AMORPHOUS CALCIUM PHOSPHATE BASED DENTAL MATERIALS

无定形磷酸钙牙科材料

• 批准号: 6516549
• 负责人: DRAGO SKRTIC
• 金额: $ 14.15万
• 依托单位: AMERICAN DENTAL ASSOCIATION FOUNDATION
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-03-01 至 2004-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6516549
• 关键词: biomaterial compatibility; biomaterial development /preparation; biomaterial evaluation; calcium phosphate; chemical structure; composite resins; dental adhesive /sealant; dental materials; human tissue; hydroxyapatites; infrared spectrometry; interferometry; polymers; scanning electron microscopy; tooth

Amorphous calcium phosphate (ACP), a key precursor in the biological formation of hydroxyapatite (HAP), has received less attention as a dental material than crystalline calcium phosphates (CaPs). ACP, however, has two properties that justify its utilization as a possible remineralizing agent: it is one of the most soluble of all the biologically important CaPs, and it exhibits the most rapid conversion to HAP. Recently we developed unique polymeric dental composites/sealants that utilized these properties of ACP to remineralize bovine enamel lesions in vitro. However, as currently formulated, these ACP composites have relatively low mechanical strength and adhesiveness to teeth. Such shortcomings may limit their wider utilization in dentistry. The objectives of this proposal are (1) to develop effective remineralizing dental composites based on ACP that will have optimal mechanical and adhesive properties while maintaining sustained release of Ca and PO4 ions, and (2) to enhance our understanding of the remineralizing behavior of these ACP-based materials, especially the major factors that control Ca and PO4 ion release and redeposition into HAP. To accomplish these objectives we propose to: l] prepare ACP fillers with structurally incorporated silica, zirconia, and/or titania; 2] develop surface- modified hybrid ACP fillers amenable to treatment by silane coupling agents; 3] explore the effects of resin composition on the, mechanical and physicochemical properties of ACP-composites, and 4] evaluate the effects of bifunctional methacrylates on the adhesion of the composites to tooth substrates. It is expected that this research will both advance our fimdamenta1 understanding of these novel bioactive composites and eventually lead to clinically useful products. The extended, time-releasing nature of these ACP based polymeric materials should be especially useful in dental sealant and adhesive applications for preventing demineralization or promoting remineralization.

无定形磷酸钙（ACP）是羟基磷灰石（HAP）生物形成的关键前体，作为牙科材料，它比结晶磷酸钙（CaP）受到的关注要少。然而，ACP具有两种特性，证明其作为可能的矿化剂的利用是合理的：它是所有生物学上重要的CaP中最可溶的一种，并且它表现出最快速的转化为HAP。最近，我们开发了独特的聚合物牙科复合材料/密封剂，利用ACP的这些特性，在体外对牛牙釉质病变进行修复。然而，如目前配制的，这些ACP复合材料具有相对低的机械强度和对牙齿的粘附。这些缺点可能会限制它们在牙科中的广泛应用。本提案的目的是（1）开发基于ACP的有效再矿化牙科复合材料，该材料将具有最佳的机械和粘合性能，同时保持Ca和PO 4离子的持续释放，以及（2）提高我们对这些ACP基材料的再矿化行为的理解，特别是控制Ca和PO 4离子释放和再沉积到HAP中的主要因素。为了实现这些目标，我们提出：1）制备具有结构上结合的二氧化硅、氧化锆和/或二氧化钛的ACP填料; 2）开发适于用硅烷偶联剂处理的表面改性的混杂ACP填料; 3]探讨了树脂组成对ACP复合材料力学性能和物理化学性能的影响，和4]评价双官能甲基丙烯酸酯对复合材料与牙齿基质的粘附的影响。预计这项研究将促进我们对这些新型生物活性复合材料的理解，并最终导致临床有用的产品。这些基于ACP的聚合物材料的延长的时间释放性质应特别适用于牙科密封剂和粘合剂应用，以防止脱矿或促进矿化。