ABRASION RESISTANT NANOSTRUCTURED DENTAL COMPOSITES

该项目的总体目标是开发新的耐磨， 纳米结构复合材料，用于直接和间接 放置修复材料。 为实现这一目标， 提出了具体目标： 该计划的具体目标1建议处理和表征 几种独特的复合结构， 无机和有机聚合物。 几个以前报道的溶胶-凝胶 已经提出了加工技术作为生产新颖的 单相和双相硅酸盐、铝酸盐和磷酸盐无孔， 胶体填料颗粒。 根据初步数据，我们 假设纳米结构耐磨牙科复合材料 可能是由这些独特的粒子与 可聚合单体。 这个相当简单但独特的组合 由一系列聚合反应产生的材料可以 导致无机物和有机物紧密结合。 的 填料颗粒本身由微孔无机交叉 可以用可聚合的聚合物浸渍的连接的网络结构 甲基丙烯酸酯单体。 这些材料的原位聚合 得到纳米级互穿无机/有机复合物。 的 硅酸盐/甲基丙烯酸酯组合将作为模型， 将评估最佳颗粒参数（尺寸、形状、密度）。 这个熟悉的组成部分组合在一起， 独特的微观结构方式被认为具有最大的潜力， 立即应用。 新组分无机有机相 已经提出了组合，这些组合提供了改善 结构的化学稳定性和/或生物相容性。 该计划的具体目标2旨在评估潜在的 这些独特的非结构化复合材料的临床性能。 评估的最初和主要重点将集中在 耐磨性评估。 拟定的体外试验利用 两体微磨损或循环表面微应力 评估磨损的技术。 将使用当前的牙科复合树脂 作为阴性对照，人牙釉质作为阳性对照。 整体 降解处理涉及耐磨性，因为它涉及 无机和有机聚合物组分的化学稳定性将 也要评估。 性能明显优于 在至少一种测试条件下， 以得到表现出改善的临床性能的复合材料， 将进一步评估。 其他重要属性 这将在最有前途的材料上进行检查，包括蠕变， 断裂韧性和强度、弹性模量、硬度和疲劳。 拟议的工作顺序旨在系统地评价 复合材料的成分和显微组织与 复合材料抗磨损的能力。 完成 拟议的工作预计将导致新的磨损的发展， 牙科复合材料。

The overall objective of this project is to develop new wear resistant, nanostructured composite materials for use as direct and indirect placement restorative materials. To achieve this objective the following specific aims have been proposed: Specific Aim 1 of the program proposes to process and characterize several unique composite structures utilizing various combinations of inorganic and organic polymers. Several previously reported sol-gel processing techniques have been proposed as methods of producing novel monophasic and diphasic silicate, aluminate and phosphate nenoporous and colloidal filler particles. Based on our preliminary data, we hypothesize that nanostructured wear resistant dental composite materials could result from the combination of these unique particles with polymerizable monomers. This rather simple but unique combination of materials which result from a series of polymerization reactions, can lead to an intimate combination of inorganic and organic substances. The filler particles themselves consist of a microporous inorganic cross linked network structure which can be impregnated with polymerizable methacrylate monomers. The in situ polymerization of these materials result in nano scale interpenetrating inorganic/organic complex. The silicate/methacrylate combination will serve as the model by which the optimal particle parameters (size, shape, density) will be evaluated. This familiar compositional component combination put together in a unique microstructural manner is felt to have the greatest potential for immediate application. New component inorganic and organic phase combinations have been proposed which offer the potential to improve the chemical stability and or biocompatibility of the structure. Specific Aim 2 of this program is designed to assess the potential clinical performance of these unique nonostructured composite materials. The initial and principal focus of the evaluation will center on the assessment of wear resistance. The proposed in vitro tests utilize wither a two body microabrasion or a cyclic surface microstressing technique to assess wear. Current dental composite resins will be used as negative controls and human enamel as a positive control. The overall degradation processed involved in wear resistance as it relates to the chemical stability of the inorganic and organic polymer components will also be assessed. Materials which perform significantly better that current dental composites under at least one test condition are likely to result in composites which exhibit improved clinical performance and will be further evaluated. Other properties of significant importance which will be examined on the most promising materials include creep, fracture toughness and strength, elastic modulus, hardness, and fatigue. The sequence of work proposed is designed to systematically evaluate the relationship between the composite composition and microstructure and the ability of composite materials to resist wear. Completion of the proposed work is expected to lead to the development of new wear resistant dental composite materials.