University of Belgrade, Faculty of Technology and Metallurgy, 11120, Belgrade, Serbia.
University of Belgrade, Institute of Nuclear Sciences, 11001, Belgrade, Serbia.
J Biomed Mater Res B Appl Biomater. 2018 Apr;106(3):1097-1107. doi: 10.1002/jbm.b.33919. Epub 2017 May 15.
The purpose of this study was to estimate the electrochemical behavior and biocompatibility of ultrafine-grained (UFG) commercially pure titanium (CPTi) and Ti-13Nb-13Zr (TNZ) alloy obtained by high-pressure torsion process. Electrochemical behavior of materials in artificial saliva at 37°C was evaluated by potentiodynamic polarization tests and electrochemical impedance spectroscopy (EIS), and the obtained results indicated that UFG TNZ alloy showed corrosion current density (j = 53 ± 5 nA cm ) which was 2 times lower compared to coarse-grained (CG) TNZ alloy (j = 110 ± 12 nA cm ) and higher corrosion resistance, while UFG CPTi and CPTi showed approximately the same corrosion rate (mean j ∼ 38-40 nA cm ). Static immersion test in artificial saliva, performed in this study, showed that the released ion concentrations from UFG materials were more than 10 times lower than the permitted concentration (the highest released Ti ion concentration from UFG CPTi and UFG TNZ alloy was 1.12 and 1.28 ppb, respectively, while permitted concentration was 15.5 ppb). The in vitro cytotoxicity tests, as the initial phase of the biocompatibility evaluation, showed that the fraction of surviving cells in all examined materials was much higher compared to the control sample and hence demonstrated absence of cytotoxicity and an increase of fibroblast cells adhesion on UFG materials surfaces. UFG CPTi and UFG TNZ alloy can be considered as promising materials for applications in dentistry due to high corrosion resistance and outstanding biocompatibility which were shown in this study. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1097-1107, 2018.
本研究旨在评估通过高压扭转工艺获得的超细晶（UFG）商用纯钛（CPTi）和 Ti-13Nb-13Zr（TNZ）合金的电化学行为和生物相容性。通过动电位极化测试和电化学阻抗谱（EIS）评估材料在 37°C 人工唾液中的电化学行为，结果表明，与粗晶（CG）TNZ 合金（j = 110 ± 12 nA cm ）相比，UFG TNZ 合金的腐蚀电流密度（j = 53 ± 5 nA cm ）低 2 倍，表现出更高的耐腐蚀性，而 UFG CPTi 和 CPTi 的腐蚀速率大致相同（平均 j ∼ 38-40 nA cm ）。本研究进行的人工唾液静态浸泡试验表明，UFG 材料释放的离子浓度比允许浓度低 10 倍以上（从 UFG CPTi 和 UFG TNZ 合金释放的最高 Ti 离子浓度分别为 1.12 和 1.28 ppb，而允许浓度为 15.5 ppb）。体外细胞毒性试验作为生物相容性评估的初始阶段，表明所有检测材料中存活细胞的比例远高于对照样品，因此证明无细胞毒性，并且成纤维细胞在 UFG 材料表面的黏附增加。UFG CPTi 和 UFG TNZ 合金由于在本研究中显示出的高耐腐蚀性和出色的生物相容性，可被认为是用于牙科应用的有前途的材料。© 2017 Wiley Periodicals, Inc. J 生物材料 Res 部分 B: 应用生物材料，106B: 1097-1107，2018。
