The influence of surface roughness on porcelain strength
The influence of surface roughness on porcelain strength
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DOI：
10.1016/s0109-5641(00)00030-0
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发表时间：
2000-11-01
期刊：
影响因子：
5
通讯作者：
Davidson, CL
中科院分区：
文献类型：
--
作者：
de Jager, N;Feilzer, AJ;Davidson, CL
目的：为了调整咬合，瓷修复体的功能表面经常被研磨，机械加工甚至是这些修复体的CAD-CAM过程的重要组成部分。本研究的目的是调查的影响，完成程序上的双轴弯曲强度的四个商业porcelains.Methods：四个商业瓷，其中两个是用于金属-陶瓷装饰（Flexo Ceram Dentine和Vita VM K68）和两个贴面和嵌体（Duceram LFC Dentine和Cerinate BODY）在这项研究中使用。对于每种瓷，使用12种不同的精加工程序生产60个盘（空组= 22 mm，h = +/-2.0 mm）。20个盘未经处理，使用高速金刚石盘研磨20个盘，并在高速研磨/抛光装置中加工20个盘。一半的样品被上釉。在这六组中的每一组中，将一半样品在80 ℃下在4%乙酸溶液中储存16 h。使用球-环方法测定双轴弯曲强度。结果：除Flexo Ceram Dentine外，其余材料的表面粗糙度与双轴向强度之间存在显著相关性：表面越光滑，样品的强度越大。双轴强度的差异可能归因于由于机械抛光或化学作用引起的表面粗糙度引起的施加载荷的应力集中。Flexo Ceram Dentine的强度不受不同表面处理影响的事实可能是由于白榴石颗粒的大小，这显然比表面缺陷和表面粗糙度更容易引起应力集中。得出的结论是，表面粗糙度决定了陶瓷材料的强度，除了材料的内部结构引起的应力集中大于由表面粗糙度和表面缺陷的组合引起的应力集中。(C)2000年牙科材料学院。由Elsevier Science Ltd.出版，版权所有。
Objectives: In order to adjust occlusion, the functional surfaces of porcelain restorations are often ground and mechanical machining is even an essential part of the CAD-CAM process for these restorations. The aim of this study was to investigate the influence of the finishing procedures on the biaxial flexure strength of four commercial porcelains.Methods: Four commercial porcelains of which two are used for metal-ceramic restorations (Flexo Ceram Dentine and Vita VM K68) and two for veneers and inlays (Duceram LFC Dentine and Cerinate BODY) are used in this study. For each porcelain, sixty discs (empty set = 22 mm, h = +/-2.0 mm) were produced using twelve different finishing procedures. Twenty discs were left untreated, twenty discs were milled, using a high-speed diamond disc, and twenty discs were machined in a high-speed grinding/polishing device. Half of the samples were glazed. In each of these six groups, half of the samples were stored for 16 h at 80 degrees C in a 4% acetic acid solution. The biaxial flexure strength was determined using the ball-on-ring method. In each group the roughness of the surface was determined and examined via SEM.Results: With the exception of Flexo Ceram Dentine, a significant correlation was found between the roughness of the surface and the biaxial strength: the smoother the surface, the stronger the sample. The differences in biaxial strength may be attributed to the stress concentration of an applied load due to the roughness of the surface caused by mechanical finishing or chemical action. The fact that the strength of Flexo Ceram Dentine was not affected by the different surface treatments is probably due to the size of the leucite particles, which apparently induce more stress concentration than the surface flaws and the roughness of the surface.Significance: It was concluded that surface roughness determines the strength of a porcelain material, except where the inner structure of the material causes greater stress concentration than that caused by the combination of surface roughness and surface flaws. (C) 2000 Academy of Dental Materials. Published by Elsevier Science Ltd. All rights reserved.