Jiménez-Sánchez María Carmen, Segura-Egea Juan José, Díaz-Cuenca Aránzazu
Department of Stomatology, Faculty of Dentistry, University of Seville, 41092 Seville, Spain.
Materials Science Institute of Seville (ICMS), Joint CSIC-University of Seville Center, 41092 Seville, Spain.
Materials (Basel). 2020 Apr 2;13(7):1641. doi: 10.3390/ma13071641.
Mineral trioxide aggregate (MTA) is considered a bioactive endodontic material, which promotes natural mineralization at the material-tooth tissue interface. MTA Repair HP stands out because of the short setting time and the quick and effective bioactive response in vitro. The bioactivity, depens on material composition and microstructure. This work is devoted to analyze MTA Repair HP microstructural features, of both the powder precursor and set material, to get insights into the material physicochemical parameters-functionality performance relationships. Transmission electron microscopy (TEM), and field emission gun scanning electron microscopy (FEG-SEM) coupled with energy-dispersive X-ray (EDX) analyses were performed. X-ray diffraction (XRD) measurements were carried out at different times to investigate setting process. Bioactivity evaluation in vitro was carried out by soaking the processed cement disk in simulated body fluid (SBF). The presented results point out those MTA Repair HP precursor material characteristics of tricalcium silicate particles of nanometric size and high aspect ratio, which provide an elevated surface area and maximized components dispersion of calcium silicate and very reactive calcium aluminate. The MTA Repair HP precursor powder nanostructure and formulation, allows a hydration process comprising silicate hydrate structures, which are very effective to achieve both fast setting and efficient bioactive response.
矿物三氧化物凝聚体（MTA）被认为是一种生物活性牙髓材料，它能促进材料与牙齿组织界面的自然矿化。MTA Repair HP因其较短的凝固时间以及在体外快速有效的生物活性反应而脱颖而出。生物活性取决于材料组成和微观结构。这项工作致力于分析MTA Repair HP粉末前驱体和凝固材料的微观结构特征，以深入了解材料物理化学参数与功能性能之间的关系。进行了透射电子显微镜（TEM）以及场发射枪扫描电子显微镜（FEG-SEM）与能量色散X射线（EDX）分析。在不同时间进行X射线衍射（XRD）测量以研究凝固过程。通过将处理过的水泥盘浸泡在模拟体液（SBF）中来进行体外生物活性评估。给出的结果指出了MTA Repair HP前驱体材料具有纳米尺寸和高纵横比的硅酸三钙颗粒的特征，这提供了高表面积以及硅酸钙和活性很高的铝酸钙的最大程度分散。MTA Repair HP前驱体粉末的纳米结构和配方允许一个包含水合硅酸结构的水化过程，这对于实现快速凝固和有效的生物活性反应都非常有效。
