High Toughness Textured Ceramics for Biomedical Use

生物医学用高韧性织构陶瓷

• 批准号: 7056190
• 负责人: Isabelle L Denry
• 金额: $ 24.27万
• 依托单位: OHIO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-02-01 至 2008-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7056190
• 关键词: X ray crystallography; aluminum; biomaterial development /preparation; ceramics; crystallization; dental materials; glass; heat; lanthanum; mechanical stress; metal dental material; phosphates; potassium; scanning electron microscopy; surface coating

DESCRIPTION: There is a high demand in dentistry for ceramics that combine high strength and optical properties matching those of natural teeth, and in reconstructive surgery for bioactive ceramics with improved toughness. Our previous work has led to the development of a novel glass-ceramic that is pressable using conventional laboratory techniques. This material exhibits a textured microstructure and improved toughness. The overall objective of this proposal is to develop a dental glass-ceramic that combines high strength and excellent esthetics. An additional goal is to produce bioactive ceramics with improved toughness. Toughness in textured materials is directly related to the degree of texture and microstructure. Our approach to producing high strength dental ceramics is to optimize the texture, promote the nucleation of a submicroscopic secondary mica phase and reduce flaw density and size in the pressed product. Texture refinement will be achieved via two techniques: heat treatment in a temperature gradient followed by heatpressing or heat treatment of the glass after heat-pressing. Microstructure will be tailored by adding AIPO4 as a nucleating agent. Translucency will be improved by adding La203 to increase the refractive index of the glassy matrix, thereby reducing the mismatch between the indices of crystalline and glassy phases. Reduction in flaw density and size will be achieved by eliminating the surface layer present after pressing and by heat treatment of the pressed ceramic to promote crack healing. Textured bioactive ceramics with improved toughness will be produced via heat pressing. The crystallization behavior and thermal properties will be studied by thermal analysis, XRD and SEM. The degree of texture will be investigated by SEM and XRD. The surface layer will be analyzed by X-ray reflectometry and EDS. The mechanical and optical properties will be measured on textured, non-textured and commercially available ceramics as controls. The experimental design uses an adaptive sampling scheme to optimize the optical and mechanical properties and integrate the different aims. Potential applications include dental restorations, dental implant superstructures, and bone replacement implants.

产品说明：在牙科学中对结合了与天然牙齿相匹配的高强度和光学性质的联合收割机的陶瓷有很高的需求，并且在重建外科中对具有改进的韧性的生物活性陶瓷有很高的需求。我们以前的工作已经导致了一种新的玻璃陶瓷，是使用传统的实验室技术压制的发展。这种材料具有纹理化的微观结构和改善的韧性。该提案的总体目标是开发一种结合高强度和优异美学的牙科玻璃陶瓷。另一个目标是生产具有改善的韧性的生物活性陶瓷。织构材料的韧性与织构和微观结构的程度直接相关。我们生产高强度牙科陶瓷的方法是优化纹理，促进亚微观二次云母相的成核，并降低压制产品中的缺陷密度和尺寸。纹理细化将通过两种技术实现：在温度梯度中进行热处理，然后进行热压或在热压后对玻璃进行热处理。微结构将通过添加AlPO4作为成核剂来定制。通过添加La2O3以增加玻璃基质的折射率，从而减少结晶相和玻璃相的折射率之间的失配，将改善半透明性。通过消除压制后存在的表面层和通过对压制陶瓷进行热处理以促进裂纹愈合，可以减少裂纹密度和尺寸。通过热压将生产具有改善的韧性的纹理生物活性陶瓷。通过热分析、XRD和SEM研究了其晶化行为和热性能。织构化程度将通过SEM和XRD进行研究。将通过X射线反射计和EDS分析表面层。将在纹理化、非纹理化和市售陶瓷（作为对照）上测量机械和光学性能。实验设计使用自适应采样方案来优化光学和机械性能，并整合不同的目标。潜在的应用包括牙科修复、牙科植入物上部结构和骨替代植入物。