Fatigue crack propagation path across the dentinoenamel junction complex in human teeth
Fatigue crack propagation path across the dentinoenamel junction complex in human teeth
复制标题
DOI：
10.1002/jbm.a.10541
复制
发表时间：
2003-07-01
影响因子：
4.9
通讯作者：
Ruse, ND
中科院分区：
文献类型：
--
作者：
Dong, XD;Ruse, ND
人类牙齿的结构应该清楚地了解，以改善临床使用的修复材料。牙本质-牙釉质交界处（DEJ）在抵抗牙齿裂纹扩展中起着关键作用。本研究的目的是通过光学和扫描电子显微镜表征疲劳断裂的珐琅-DEJ-牙本质复合物，以确定珐琅-DEJ-牙本质复合物的断裂韧性，并研究DEJ对其疲劳裂纹扩展路径的影响。结果表明，牙本质-牙釉质- dej复合物的断裂韧性为1.50 ~ 0.28 Mpa.m（1/2）。本研究结果表明，DEJ复合物在抵抗牙本质裂纹扩展过程中发挥了关键作用。DEJ复合物在牙本质和牙釉质之间的界面上大约有100到150微米宽的区域。DEJ配合物的增韧机制可以用裂纹路径在其上扩展时发生偏转来解释。了解裂纹偏转的机制有助于改善牙本质复合材料和陶瓷-水泥界面质量，从而降低临床修复失败的风险。两者都可以看作是由一层高强度和高硬度的材料结合到一个更软但更硬的基质（牙本质）组成的。在临床上，粘结剂或骨水泥层在提高这些修复体的强度方面可能起着至关重要的作用。(C) 2003 Wiley期刊有限公司
The human tooth structures should be understood clearly to improve clinically used restorative materials. The dentinoenamel junction (DEJ) plays a key role in resisting crack propagation in teeth. The aim of this study was to determine the fracture toughness of the enamel-DEJ-dentin complex and to investigate the influence of the DEJ on the fatigue crack propagation path across it by characterizing fatigue-fractured enamel-DEJ-dentin complexes using optical and scanning electron microscopy. The results of this study showed that the fracture toughness of the enamel-DEJ- dentin complex was 1.50 - 0.28 Mpa.m(1/2). Based on the results of this investigation, it was concluded that the DEJ complex played a critical role in resisting crack propagation from enamel into dentin. The DEJ complex is, approximately, a 100 to 150 mum broad region at the interface between enamel and dentin. The toughening mechanism of the DEJ complex may be explained by the fact that crack paths were deflected as cracks propagated across it. Understanding the mechanism of crack deflection could help in improving dentin-composite as well as ceramic-cement interfacial qualities with the aim to decrease the risk of clinical failure of restorations. Both can be viewed as being composed from a layer of material of high strength and hardness bonded to a softer but tougher substratum (dentin). The bonding agent or the luting cement layer may play the critical role of the DEJ in improving the strength of these restorations in clinical situations. (C) 2003 Wiley Periodicals, Inc.