EFFECT OF MICROSTRUCTURE ON WEAR OF DENTAL CERAMICS

陶瓷材料在牙科应用中获得了突出的地位， 尤其是在修复牙冠和咬合面方面。磨损量 烤瓷修复体常与釉质相对立 这是限制修复体寿命的关键因素。然而，可用的 有关这些材料磨损性能的数据和信息有限。 特别是陶瓷微结构、口腔环境和口腔环境的影响。 机械加工对磨损的影响，以及天然牙釉质与机械加工相对的磨损行为。 陶瓷修复体，还不为人所知。该项目的目标是 测定显微结构对牙科陶瓷磨损量的影响 反牙釉质，并评估机械加工损伤的可能影响 以及环境对所选牙科陶瓷磨损的影响。六个具体目标 主要研究内容如下：(1)确定显微组织对磨损的影响 为了确定最佳磨损性能的最佳显微组织，(2)比较 含损伤形成过程的微断裂磨损机理 机械加工中的疲劳断裂与材料去除过程 量化机械加工损伤的影响(包括表面粗糙度、 表面完整性和涂抹层)对所选牙科陶瓷的磨损， (4)评价环境(空气、水、人工唾液)的影响 对选定的牙科陶瓷材料的磨损性能进行了研究。(5)表面效果评价 牙科陶瓷材料磨损的化学回火及(6)检验 天然牙釉质在不同陶瓷显微结构下的磨损 各种环境。这一项目的成果将有助于 为先进材料的选择和微结构设计提供指导 基于磨损量的牙科修复材料的最佳性能 修复和对立的天然珐琅。中的一个重要问题 本研究是微观结构对生物多样性影响的相互作用 磨损、疲劳和机械加工。因此，微破裂过程 将涉及疲劳(项目2)和机械加工(项目1)进行比较 与那些观察磨损的人一起制定一些指导方针，以建立 具有最佳磨损性能的最佳显微组织，不会产生不利影响 影响疲劳和可加工性。

Ceramic materials are gaining a prominent position in dental applications, particularly in the restoration of crowns and occlusal surfaces. Wear of the restoration and the enamel opposing the ceramic restoration is often a key factor limiting the life of the restoration. However, the available data and information on wear performance of these materials are limited. Particularly, the effects of ceramic microstructure, oral environment, and machining on wear, and the wear behavior of natural enamel opposing the ceramic restoration, are not known. The objectives of this project are to determine the effect of microstructure on wear of dental ceramics and the opposing enamel, and to evaluate the possible effects of machining damage and environment on wear of selected dental ceramics. Six specific aims will be investigated: (1) determine the effect of microstructure on wear to define an optimum microstructure for best wear performance, (2) compare the microfracture wear mechanisms with the process of damage formation in fatigue and fracture and the material removal process in machining, (3) quantify the effects of machining damage (including surface roughness, surface integrity, and smear layers) on wear of selected dental ceramics, (4) evaluate the effect of environment (air, water, and artificial saliva) on wear of selected dental ceramics, (5) evaluate the effect of surface chemical tempering on wear of selected dental ceramics, and (6) examine wear of natural enamel tested against different ceramic microstructures in various environments. The results of this project will be instrumental in providing guidelines for selection and microstructural design of advanced dental restorative materials for an optimum performance based on wear of the restoration and the opposing natural enamel. An important issue in this research is the interplay between the effects of microstructure on wear, fatigue, and machining. Therefore, the microfracture processes involved in fatigue (Project 2) and machining (Project 1) will be compared with those observed for wear to develop some guidelines for establishing an optimum microstructure for best wear performance, without adversely affecting fatigue and machinability.