RESTORATIVE MATERIAL WEAR FACTORS

聚合物基修复体材料的破裂通常是由于 造成磨损的化学和物理压力的组合。目前， 临床磨损行为最可靠的预测指标是计划周密的 临床研究。尽管在某些情况下可能会将 这类研究的结果与体外试验，这种相关性并不 始终为预测磨损提供可靠的科学依据。 疲劳磨损是一种重要的疲劳磨损现象。 一些修复材料的降解，特别是“微填充体” 复合材料，在承受应力的情况下使用。这是相对的 修复材料研究中被忽视的领域。 在这项研究中将采用几种新的方法来实现 对聚合物材料疲劳磨损的认识 修复牙科。 与目前用作基质的树脂材料相似的一系列树脂材料 用于牙科复合材料的树脂将由一家工业承包商准备。 一些样品将填充少量的硅烷化胶体二氧化硅， 如在实际中所做的，以控制基质材料的粘度。全 样品将根据固化程度和玻璃化转变温度进行表征。别针- 光盘磨损测试将利用合适的触笔几何形状来诱导 亚表面疲劳磨损。动态拉伸和剪切疲劳试验将 按照相关的ASTM规范完成。使用这样的属性 测量的有限元建模技术将被用来模拟销对销- 碟片磨损行为。最后，疲劳断裂面、磨损表面和 磨粒将使用经典几何和分形几何进行表征 方法：研究方法。

The breakdown of polymer-based restorative materials is often due to a combination of chemical and physical stresses that cause wear. Presently, the most reliable predictor of clinical wear behavior is the well-planned clinical study. Although it is possible in some cases to correlate the results of such studies with an in-vitro test, such correlations do not always provide a sound scientific basis for predicting wear. It is believed that fatigue induced wear is an important phenomenon in the degradation of some restorative materials, particularly the "microfilled" composites, when used in a stress-bearing situation. This is relatively neglected area of restorative materials research. Several novel approaches will be employed in this study in order to arrive at an understanding of fatigue-induced wear of polymer materials used in restorative dentistry. A series of resin materials similar to those presently used as matrix resins for dental composites will be prepared by an industrial contractor. Some samples will be filled with low amounts of silanated colloidal silica, as is done in practice to control the viscosity of matrix materials. All samples will be characterized with respect to degree of cure and Tg. Pin- on-disc wear testing will utilize an appropriate stylus geometry to induce subsurface fatigue wear. Dynamic tensile and shear fatigue testing will be done following relevant ASTM specifications. Employing the properties thus measured, finite element modeling techniques will be used to mimic pin-on- disc wear behavior. Finally, fatigue fracture surfaces, wear surfaces, and wear debris will be characterized using classical and fractal geometric methods.