AMORPHOUS CALCIUM PHOSPHATE BASED DENTAL MATERIALS

无定形磷酸钙牙科材料

• 批准号: 6362939
• 负责人: DRAGO SKRTIC
• 金额: $ 13.9万
• 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/6362939
• 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，与结晶磷酸钙 (CaP) 相比，作为牙科材料受到的关注较少。然而，ACP 有两个特性证明其作为一种可能的再矿化剂是合理的：它是所有生物学上重要的 CaP 中溶解度最高的一种，并且它表现出向 HAP 的最快转化。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 的这些特性在体外使牛牙釉质病变再矿化。然而，按照目前的配方，这些 ACP 复合材料的机械强度和牙齿粘附性相对较低。这些缺点可能会限制它们在牙科中的更广泛应用。该提案的目标是 (1) 开发基于 ACP 的有效再矿化牙科复合材料，该复合材料将具有最佳的机械和粘合性能，同时保持 Ca 和 PO4 离子的持续释放，以及 (2) 增强我们对这些材料的再矿化行为的理解。 ACP基材料，特别是控制Ca和PO4离子释放和再沉积成HAP的主要因素。为了实现这些目标，我们建议： l] 制备结构上掺入二氧化硅、氧化锆和/或二氧化钛的 ACP 填料； 2]开发适合硅烷偶联剂处理的表面改性杂化ACP填料； 3] 探索树脂组合物对 ACP 复合材料机械和物理化学性能的影响，4] 评估双官能甲基丙烯酸酯对复合材料与牙齿基质粘合的影响。预计这项研究将增进我们对这些新型生物活性复合材料的基本理解，并最终产生临床上有用的产品。这些基于 ACP 的聚合物材料的延长、缓释特性在牙科密封剂和粘合剂应用中尤其有用，可防止脱矿质或促进再矿化。