Borrero-Lopez Oscar, Guiberteau Fernando, Zhang Yu, Lawn Brian R
Departamento de Ingeniería Mecánica, Energética y de los Materiales, Universidad de Extremadura, 06006, Badajoz, Spain.
Departamento de Ingeniería Mecánica, Energética y de los Materiales, Universidad de Extremadura, 06006, Badajoz, Spain.
J Mech Behav Biomed Mater. 2020 May;105:103722. doi: 10.1016/j.jmbbm.2020.103722. Epub 2020 Mar 12.
The objective of this study is to elucidate the interdependence of competing mechanical degradation processes in biphasic dental materials with ceramic constituents in the region of high-pressure occlusal loading. It is hypothesized that wear resistance in this region correlates inversely with basic material parameters (modulus, hardness, toughness, strength) evaluated from 'standardized' test specimens. Ball-on-flat wear tests in simulation of oral function are used to quantify susceptibility to protracted sliding contact damage. Wear rates for this class of dental material tend to increase with quasistatic parameter values, so the latter do not provide a reliable guide to longevity. The generation of severe-wear facets involves cumulative quasiplastic deformation and microcrack coalescence at the grain level. It is implied that interplay between wear and fracture mechanisms should be an important consideration in future microstructural design of dental ceramics, especially in the quest to balance durability against esthetics.
本研究的目的是阐明在高压咬合负载区域中，具有陶瓷成分的双相牙科材料中相互竞争的机械降解过程之间的相互依存关系。据推测，该区域的耐磨性与从“标准化”测试样本评估的基本材料参数（模量、硬度、韧性、强度）呈反比。模拟口腔功能的球-平面磨损试验用于量化对长期滑动接触损伤的敏感性。这类牙科材料的磨损率往往会随着准静态参数值的增加而增加，因此后者并不能为材料的使用寿命提供可靠的指导。严重磨损小面的产生涉及到在晶粒水平上的累积准塑性变形和微裂纹合并。这意味着磨损和断裂机制之间的相互作用应成为未来牙科陶瓷微观结构设计中的一个重要考虑因素，特别是在寻求平衡耐久性和美观性方面。
