Effect of depth and tubule direction on ultimate tensile strength of human coronal dentin
Effect of depth and tubule direction on ultimate tensile strength of human coronal dentin
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DOI：
10.4012/dmj.22.39
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发表时间：
2003-03-01
影响因子：
2.5
通讯作者：
Sano, H
中科院分区：
文献类型：
--
作者：
Inoue, S;Pereira, PNR;Sano, H
本研究的目的是评价牙本质深度和牙本质小管方向对人牙本质极限拉伸强度（UTS）的影响。从近中和远中（对于小管平行于拉力的样本;平行组）或从咬合面和牙髓面（垂直组）修剪0.5 mm厚的牙本质板，以将浅、中、深区域的横截面积减少至0.25 mm（2），并进行微拉伸测试。从平行组的断裂试样的SEM显微照片，小管密度进行了研究。对于平行组和垂直组，浅表牙本质的UTS显著高于深层牙本质。牙本质浅层小管密度明显低于牙本质中层和深层小管密度。当对深层牙本质进行微拉伸粘结试验时，牙本质的内聚破坏可能在相对低的拉伸应力下发生。
The purpose of this study was to evaluate the effect of dentin depth and tubule direction on the ultimate tensile strength (UTS) of human dentin. Dentin slabs of 0.5-mm thickness were trimmed either from the mesial and distal (for specimens with the tubules parallel to the tensile force; parallel group) or from the occlusal and pulpal surfaces (perpendicular group) to reduce the cross-sectional area of the superficial, middle, and deep regions to 0.25 mm(2), and subjected to microtensile testing. From SEM photomicrographs of the fractured specimens of the parallel group, the tubule density was investigated. For both parallel and perpendicular groups, superficial dentin showed a significantly higher UTS than deep dentin. The tubule density of superficial dentin was significantly lower than that of middle and deep dentin. When performing the microtensile bond test to deep dentin, it is possible that cohesive failure of dentin can occur at relatively low tensile stresses.