RESTORATIVE MATERIAL WEAR FACTORS

修复材料磨损因素

• 批准号: 6892106
• 负责人: George R. Baran
• 金额: $ 37.63万
• 依托单位: TEMPLE UNIV OF THE COMMONWEALTH
• 依托单位国家: 美国
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-07-01 至 2008-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6892106
• 关键词: biomaterial development /preparation; biomaterial evaluation; composite resins; dental material wear; elasticity; glass; mechanical stress; polyethylenes; tensile strength

DESCRIPTION (provided by applicant): Dental composites continue to be favored restorative materials in the anterior region, although their use is limited to single-unit restorations. In both anterior and posterior restorations, lifetimes are limited by two factors: polymerization shrinkage and mechanical failure. Although composite properties continue to improve, their toughness, durability, and strength remain inadequate, particularly when large restorations are considered. Wear is still a concern in approximal and occlusal contact areas. Studies related to the resin matrix component currently focus on the shrinkage problem; studies related to the filler component currently focus on alternative filler morphologies, panicle sizes, and filler composition. Relatively little in the dental community has been done concerning the filler-matrix interface beyond exploring silanation variables, although the structural composites community at large has recently focused on the concept of an engineered interphase as a means of improving composite properties. However, that community is primarily interested in fiber-reinforced, not particulate-reinforced composites. We propose to adapt this concept for the design of stronger and especially tougher dental composites in order to expand the indications for composite restorations. In designing new materials, it is useful to adopt a methodology that shortens development time and has predictive power. We have experienced success in implementing finite element (FE) modeling for predicting the modulus and toughness of particulate filled composites, and propose extending this approach to more complex composite systems in combination with an experimental approach that validates the FE models. Specifically, we propose the following aims: 1.) To fabricate, model, and predict toughening of matrix polymers containing ductile organic additives; our hypothesis is that the presence of such compounds (% elongation=400%) promotes plasticity and energy dissipation.; 2.) To fabricate, model, and predict toughening of composites with novel ductile interphases; our hypothesis is that the presence of the interphase provides additional plasticity and augments toughening by the crack-pinning mechanism; and 3.) To model the effect of filler particle size and shape on composite strength and toughness. The outcome of this work will be a blueprint for the rational design of longer-lived composites.

描述（由申请人提供）：牙科复合材料仍然是前牙区最受欢迎的修复材料，尽管其使用仅限于单单元修复。在前牙和后牙置换中，使用寿命受到两个因素的限制：聚合收缩和机械失效。虽然复合材料的性能不断提高，但它们的韧性、耐久性和强度仍然不足，特别是当考虑到大尺寸时。磨损仍然是一个问题，在近端和咬合接触区。 与树脂基质组分相关的研究目前集中在收缩问题上;与填料组分相关的研究目前集中在替代填料形态、颗粒尺寸和填料组成上。相对较少的牙科社区已经做了关于填料-基质界面以外的探索硅烷化变量，虽然结构复合材料社区在最近集中在工程界面的概念，作为一种手段，提高复合材料的性能。然而，该社区主要对纤维增强复合材料感兴趣，而不是颗粒增强复合材料。我们建议将这一概念用于设计更坚固、更坚韧的牙科复合材料，以扩大复合材料的适应症。 在设计新材料时，采用缩短开发时间并具有预测能力的方法是有用的。我们已经经历了成功的实施有限元（FE）建模预测的模量和韧性的颗粒填充复合材料，并建议将这种方法扩展到更复杂的复合材料系统结合实验方法，验证FE模型。具体而言，我们提出以下目标：（1）。制造、模拟和预测含韧性有机添加剂的基体聚合物的增韧;我们假设这类化合物的存在（%伸长率=400%）促进塑性和能量耗散。2.）的情况。为了制造、建模和预测具有新型韧性界面的复合材料的增韧;我们的假设是界面的存在提供了额外的塑性并通过裂纹钉扎机制增强增韧;以及3）模拟填料颗粒尺寸和形状对复合材料强度和韧性的影响。 这项工作的结果将是一个蓝图，合理设计的长寿命复合材料。