期刊
BIOMATERIALS
卷 27, 期 9, 页码 2131-2140出版社
ELSEVIER SCI LTD
DOI: 10.1016/j.biomaterials.2005.10.005
关键词
dentin; fatigue; fracture; tubule orientation
资金
- NIDCR NIH HHS [1R03DE014640-01] Funding Source: Medline
In this study the influence of tubule orientation on the strength of human dentin under static and cyclic loads was examined. Rectangular beams were sectioned from the coronal dentin of virgin extracted molars (N = 83) and then loaded in quasi-static 4-point flexure or 4-point flexural fatigue to failure. The flexure strength, energy to fracture and fatigue strength were evaluated for specimens with the dentin tubules aligned parallel (theta = 0 degrees) and perpendicular (theta = 90 degrees) to the plane of maximum normal stress. Results from monotonic loading showed that both the flexural strength and energy to fracture of dentin specimens with theta = 0 degrees were significantly greater than those with theta = 90 degrees. Furthermore, the apparent endurance strength of dentin with theta = 0 degrees (44 MPa) was significantly greater than that of the dentin with theta = 90 degrees (24 MPa). The ratio of apparent endurance strength (for fully reversed loading) to the flexure strength for theta = 0 degrees and theta = 90 degrees was 0.41 and 0.28, respectively. Although the influence of tubule orientation was most important to mechanical behavior, the flexure strength and energy to fracture also decreased with an increase in tubule density. According to differences in the fatigue strength with tubule orientation, restorative practices promoting large cyclic normal stresses perpendicular to the tubules would be more likely to facilitate fatigue failure in dentin with cyclic loading. (C) 2005 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据