Viscoelastic Modeling Aided Experimental Optimization toward Fracture-Resistant Porcelain-Veneered Zirconia and Lithium Disilicate Restorations

粘弹性模型辅助抗裂瓷贴面氧化锆和二硅酸锂修复体的实验优化

• 批准号: 10304391
• 负责人: JEONGHO KIM
• 金额: $ 41.03万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-30 至 2024-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10304391
• 关键词: Acute; Anatomy; Behavior; Cells; Ceramics; Clinical; Computing Methodologies; Dental Enamel; Dental Porcelain; Dental Prosthesis; Dental Veneer Application; Dental crowns; Dentin; Development; Elements; Engineering; Esthetics; Failure; Fatigue; Fracture; Goals; Healthcare; High temperature of physical object; Incidence; Knowledge; Laboratories; Lithium; Longevity; Measurement; Mechanics; Medical; Metals; Methodology; Methods; Modeling; Morbidity - disease rate; Motion; Oral cavity; Oxides; Procedures; Process; Prosthesis; Prosthesis Design; Public Health; Quality of life; Research; Residual state; Resistance; Solid; Stress; Stress Fractures; Structure; System; Testing; Time; Work; clinically relevant; cost; design; experience; improved; innovation; knowledge base; next generation; novel; predictive modeling; premature; restoration; restorative dentistry; simulation; viscoelasticity; zirconium oxide

Project Summary/Abstract Dental crowns and bridges are usually constructed by applying an esthetic porcelain veneer to a strong core. Ceramic core materials, such as zirconia and lithium disilicate, are currently favored for their ease of fabrication and for their strength. While porcelain chipping and fractures are observed in all types of veneered dental prostheses, they are particularly prevalent in porcelain-veneered zirconia. The high chipping/fracture rate is due predominantly to residual stresses introduced by the high-temperature veneering process. However, comprehensive knowledge of key material, design, and processing parameters that govern residual stresses remains obscure. The long-term goal of this project is to improve the fracture resistance of porcelain-veneered prostheses through the reduction of deleterious residual tensile stresses, in conjunction with superior design of a graded veneer/core interface. Accordingly, the overall objectives in this application are to develop a rigorous viscoelastic graded finite element method to guide the design of next-generation fracture-resistant porcelain- veneered ceramic prostheses, and to use clinically relevant fracture mechanics test methods to validate finite element model predictions. The central hypothesis is that the incidence of chipping and fracture of porcelain- veneered ceramics can be reduced to the levels seen in porcelain-fused-to-metal prostheses, through the optimization of material, design, and processing parameters. This hypothesis is formulated on the basis of preliminary results produced in the applicants' laboratories. To test this hypothesis, we will pursue two specific aims: (1) Develop a rigorous viscoelastic graded finite element model, and use this model to optimize the residual stress profile in anatomically-correct porcelain-veneered prostheses through the tailoring of material, design, and processing parameters. Validate model predictions against direct measurement using the Vickers microindentation method; (2) Experimentally quantify resistance to veneer chipping and fracture of porcelain- veneered prostheses with optimal material, design, and processing parameters relative to their bilayer counterparts and a commercial porcelain-fused-to-metal restoration, using edge-chipping methodology and mouth-motion fatigue testing. The approach is innovative because it departs from the status quo by developing a novel viscoelastic graded finite element method and utilizing this model to design continuously graded veneer/core interfaces. The proposed research is significant because it vertically advances the understanding of how stress profiles in all-ceramic prostheses can be tailored for better fracture resistance. Ultimately, such knowledge will bring us closer to a solution of a pervasive clinical problem—chipping, delamination and fracture of porcelain veneered prostheses—leading to reduced morbidity of dental prostheses and cost of replacement to the public.

项目摘要/摘要 牙冠和牙桥通常是通过在坚固的核心上涂上一层美观的瓷贴面来建造的。 陶瓷芯材，如氧化锆和二硅酸锂，目前因其易于制造而受到青睐。 以及他们的力量。而在所有类型的贴面牙体中都可以观察到瓷屑和折裂 假体，它们在瓷贴面氧化锆中特别普遍。较高的碎屑/折断率是 主要是由于高温贴面过程中引入的残余应力。然而， 全面了解控制残余应力的关键材料、设计和工艺参数 仍然鲜为人知。本项目的长期目标是提高烤瓷贴面的抗折性能。 通过减少有害的残余拉应力，结合卓越的设计 分级的单板/核心接口。因此，本应用程序的总体目标是开发一个严格的 粘弹性梯度有限元方法指导下一代抗折陶瓷的设计 贴面陶瓷假体，并使用临床相关的断裂力学测试方法来验证有限元 元素模型预测。中心假设是瓷器碎裂和断裂的发生率- 贴面陶瓷可以降低到瓷熔附金属假体中的水平，通过 材料、设计和工艺参数的优化。这一假设是在以下基础上提出的 申请者实验室产生的初步结果。为了验证这一假设，我们将研究两个具体的 目的：(1)建立一个严格的粘弹性梯度有限元模型，并利用该模型进行优化。 通过材料的剪裁在解剖矫正的贴面瓷修复体中的残余应力分布， 设计和工艺参数。使用Vickers验证模型预测与直接测量的对比 微压痕法；(2)实验量化瓷贴面的抗碎裂和断裂性能。 具有相对于双层的最佳材料、设计和工艺参数的贴面假体 对应物和商用烤瓷熔附金属修复体，使用切边方法和 口腔运动疲劳试验。这种方法是创新的，因为它通过开发 一种新型粘弹性梯度有限元方法及其在连续梯度设计中的应用 单板/核心接口。这项拟议的研究具有重要意义，因为它垂直地推进了对 了解如何定制全陶瓷假体的应力分布，以获得更好的抗折性。最终，这样的 知识将使我们更接近解决普遍存在的临床问题-碎屑、分层和 瓷贴面修复体的断裂-导致牙修复体的发病率和成本的降低 更新换代向公众。