The importance of microstructural variations on the fracture toughness of human dentin.
The importance of microstructural variations on the fracture toughness of human dentin.
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DOI：
10.1016/j.biomaterials.2012.10.032
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发表时间：
2013-01
期刊：
影响因子：
14
通讯作者：
Arola, Dwayne D.
中科院分区：
文献类型：
--
作者：
Ivancik, Juliana;Arola, Dwayne D.
人牙本质的裂纹扩展阻力的特点是作为相对距离DEJ和相应的微观结构的函数。从无龋的第三磨牙冠状面制备致密的牙本质拉伸标本。标本从外部、中间或内部牙本质切片。在模式I准静态载荷下实现了稳定的裂纹扩展，其中裂纹与小管在平面内取向，并且裂纹扩展阻力的特征在于起始（Ko）、增长（Kg）和平台（Kp）韧性。一个混合的方法也被用来量化的贡献占主导地位的机制，整体韧性。结果表明，人牙本质各区域的裂纹扩展阻力随裂纹扩展而增加，内层牙本质的断裂韧性（2.2± 0.5MPa·m0.5）明显低于中层牙本质（2.7± 0.2MPa·m0.5）和外层牙本质（3.4± 0.3MPa·m0.5）。外增韧，主要由裂纹桥接，估计会导致平均增加26%的断裂能在所有三个区域。基于这些发现，由于引入缺陷的可能性更大，并且随着深度的增加，断裂韧性降低，因此延伸到深层牙本质中的牙釉质更有可能导致牙齿断裂。
The crack growth resistance of human dentin was characterized as a function of relative distance from the DEJ and the corresponding microstructure. Compact tension specimens were prepared from the coronal dentin of caries-free 3rd molars. The specimens were sectioned from either the outer, middle or inner dentin. Stable crack extension was achieved under Mode I quasi-static loading, with the crack oriented in-plane with the tubules, and the crack growth resistance was characterized in terms of the initiation (Ko), growth (Kg) and plateau (Kp) toughness. A hybrid approach was also used to quantify the contribution of dominant mechanisms to the overall toughness. Results showed that human dentin exhibits increasing crack growth resistance with crack extension in all regions, and that the fracture toughness of inner dentin (2.2±0.5 MPa•m0.5) was significantly lower than that of middle (2.7±0.2 MPa•m0.5) and outer regions (3.4±0.3 MPa•m0.5). Extrinsic toughening, composed mostly of crack bridging, was estimated to cause an average increase in the fracture energy of 26% in all three regions. Based on these findings, dental restorations extended into deep dentin are much more likely to cause tooth fracture due to the greater potential for introduction of flaws and decrease in fracture toughness with depth.
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影响因子：
3
作者：
GARBEROGLIO, R;BRANNSTROM, M
通讯作者：
BRANNSTROM, M
影响因子：
4.2
作者：
CARRIGAN, PJ;MORSE, DR;SINAI, IH
通讯作者：
SINAI, IH
影响因子：
2.5
作者：
Inoue, S;Pereira, PNR;Sano, H
通讯作者：
Sano, H
DOI：
10.1016/j.jmbbm.2009.12.004
发表时间：
2010-05-01
影响因子：
3.9
作者：
Bechtle, Sabine;Fett, Theo;Schneider, Gerold A.
通讯作者：
Schneider, Gerold A.
影响因子：
6
作者：
Arola, D.;Bajaj, D.;Zhang, D.
通讯作者：
Zhang, D.