Local properties of a functionally graded interphase between cementum and dentin
Local properties of a functionally graded interphase between cementum and dentin
复制标题
DOI：
10.1002/jbm.a.30105
复制
发表时间：
2004-09-01
影响因子：
4.9
通讯作者：
Marshall, GW
中科院分区：
文献类型：
--
作者：
Ho, SP;Balooch, M;Marshall, GW
自然界面的研究可以提供必要的信息，工程功能梯度生物材料的生物工程应用。在这项研究中，机械，结构和化学成分的变化与牙骨质和牙本质之间的区域进行了研究，使用纳米压痕，显微压痕，光学显微镜，和拉曼显微光谱技术。3毫米厚的横切面（N = 5）从消毒的人磨牙的根尖三分之一的根获得。在室温下使用金刚石刀和超薄切片机对样品进行超声切割。制备100 μ m厚的纵向研磨切片，并用von Kossa染色剂染色，以确定磨牙根内的矿化区域。拉曼显微光谱用于测定牙骨质和牙本质本体组织之间的相对无机含量，主要是磷灰石（PO（4）（3-）nu（1），模式在960 cm（-1））和有机含量，主要是胶原（C-H伸缩在2940 cm（-1））。微压痕和纳米压痕的结果表明，从牙骨质到牙本质的硬度在100至200 μ m的宽度范围内逐渐过渡。然而，纳米压痕的牙骨质和牙本质硬度数据的变化（0.62 +/- 0.21，0.77 +/- 0.14 GPa）大于微压痕（0.49 +/- 0.03，0.69 +/- 0.07 GPa）。在100至200 μ m的区域内，存在10至50 μ m的纤维状亲水性牙骨质-牙本质连接部（CDJ），其机械性能显著低于牙骨质或牙本质侧的CDJ。光学显微镜显示牙骨质和牙本质之间的100至200 μ m的半透明区域。拉曼显微光谱的结果表明，在80至140微米宽的有机和无机组合物的变化。得出的结论是，形态和生物力学不同的CDJ在于更广泛的牙骨质-牙本质界面。因此，牙骨质、牙本质和界面可以被分类为牙根内的功能分级的牙组织。(C)2004 Wiley Periodicals，Inc.
The study of natural interfaces may provide information necessary to engineer functionally graded biomaterials for bioengineering applications. In this study, the mechanical, structural, and chemical composition variations associated with a region between cementum and dentin were studied with the use of nanoindentation, microindentation, optical microscopy, and Raman microspectroscopy techniques. Three-millimeter-thick transverse sections (N = 5) were obtained from the apical one-third of the roots of sterilized human molars. The samples were ultrasectioned at room temperature with the use of a diamond knife and an ultramicrotome. Longitudinal ground sections of 100 mum thickness were prepared and stained with von Kossa stain to determine the mineralized regions within the molar roots. Raman microspectroscopy was used to determine the relative inorganic content, mainly apatite (PO(4)(3-)nu(1), mode at 960 cm(-1)) and organic content, mainly collagen (C-H stretch at 2940 cm(-1)) between cementum and dentin bulk tissues. The microindentation and nanoindentation results indicated a gradual transition in hardness from cementum to dentin over a width ranging from 100 to 200 mum. However, the variation in hardness data for cementum and dentin by nanoindentation was larger (0.62 +/- 0.21, 0.77 +/- 0.14 GPa) than from microindentation (0.49 +/- 0.03, 0.69 +/- 0.07 GPa). Within the 100 to 200 mum region there was a 10 to 50 mum fibrillar hydrophilic cementum-dentin junction (CDJ) with mechanical properties significantly lower than either the cementum or the dentin side of CDJ. Light microscopy revealed a 100 to 200 mum translucent region between cementum and dentin. Raman microspectroscopy results showed a variation in organic and inorganic composition 80 to 140 mum wide. It was concluded that a morphologically and biomechanically different CDJ lies within a wider cementum-dentin interphase. Hence, cementum, dentin, and the interphase can be classified as a functionally graded dental tissue within the root of a tooth. (C) 2004 Wiley Periodicals, Inc.