RESTORATIVE MATERIAL WEAR FACTORS

这项研究的长期目标是开发一种预测性的 牙科修复材料磨损的模型。 在本申请中， 后牙复合修复材料的疲劳/磨损 研究了 成功实现项目目标可以使 体外设计和评价新的修复材料， 需要长期的临床试验。 这将允许速度更快的 向公众介绍更有效和更具成本效益的材料。 将检验以下零假设：A。 治愈的程度 并且溶剂吸附不影响聚合物基体的疲劳/磨损 复合材料; B. 销盘寿命预测/参数 疲劳/磨损研究不同于从剪切获得的那些， 弯曲和压痕模式疲劳试验; C. 表面形态 磨损和疲劳的表面是无关的磨损机制。 这些具体目标旨在帮助检验这些假设： 1. 为了获得两种不同程度的固化， 关于玻璃化转变行为表征复合材料， 专利牙科修复材料的材料代表; 材料也将浸泡在水/乙醇溶液中，以模拟 暴露于口腔液体。 2. 为了获得剪切，弯曲， 和压痕模式，并推导出这些寿命参数 实验 3. 采用销盘技术产生疲劳 磨损，并将这些结果与特定的 目标2，以及有限元分析。 4. 发展和完善 静态和动态压痕以及裂纹的有限元模型 在颗粒增强复合材料中的传播。 5. 雇用 表征疲劳/磨损表面的形态测量技术。

The long-term objective of this study is the development of a predictive model for the wear of dental restorative materials. In this application, the fatigue/wear of posterior composite restorative materials is to be investigated. Successful attainment of the project objectives could allow in vitro design and evaluation of new restorative materials without the need for lengthy clinical trials. This should permit the speedier introduction of more effective and cost-efficient materials to the public. The following null hypotheses are to be tested: A. that degree of cure and solvent sorption do not affect the fatigue/wear of a polymer matrix composite; B. that the lifetime predicting/parameters from pin-on-disc fatigue/wear studies are dissimilar from those obtained from shear, bending, and indentation mode fatigue tests; C. that surface morphology of worn and fatigued surfaces is unrelated to wear mechanisms. These specific aims have been designed to aid in testing these hypotheses: 1. To obtain, polymerize to two different degrees of cure, and characterize with respect to glass transition behavior a composite material representative of proprietary dental restorative materials; the material will also be soaked in a water/ethanol solution to simulate exposure to oral fluids. 2. To obtain fatigue data in shear, bending, and indentation modes, and derive the lifetime parameters for these experiments. 3. To employ the pin-on-disc technique to generate fatigue wear in composite samples, and relate these results to those from specific aim 2, as well as to finite element analyses. 4. To develop and refine finite element models of static and dynamic indentation, and crack propagation in particulate reinforced composite materials. 5. To employ morphometric techniques to characterize fatigue/wear surfaces.