Department of Materials Engineering, Tarbiat Modares University, Tehran, P.O. Box 14115-143, Iran.
Department of Materials Engineering, Tarbiat Modares University, Tehran, P.O. Box 14115-143, Iran.
Mater Sci Eng C Mater Biol Appl. 2020 Apr;109:110637. doi: 10.1016/j.msec.2020.110637. Epub 2020 Jan 7.
Titanium alloys are commonly used in orthopedic devices due to their good corrosion resistance, high specific strength and excellent biological response. The direct contact between the implant surface and the host tissue results in notable effect of surface properties such as surface topography on the biological responses. The aim of this study is to investigate the effect of frequency of pulsed Nd-YAG laser on Ti6Al4V alloy surface topography and its influence on the improvement of biocompatibility while other laser parameters kept constant. The range of applied frequency values were selected from 1 to 20 Hz. The range of surface roughness was found between 452 nm and 3.37 μm. The untreated sample and also samples with the highest and the lowest average surface roughness parameter were subjected to the further analyses. Characterization of the samples was performed with surface roughness tester, Scanning Electron Microscopy (SEM), and Atomic Force Microscopy (AFM). The high rate of melt and solidification during the laser treatment led to the martensite formation and consequently an increase about 12-25% in hardness. Furthermore, in vitro study was carried out using MG-63 osteoblast like cells. The analyses of cell viability for 3 culture times, cell morphology and cell spreading area revealed that sample with the highest average surface roughness parameter is more biocompatible. 10 Hz frequency was found as the optimum parameter which led to the highest surface roughness and thus the biocompatibility enhancement. In conclusion, the pulsed Nd-YAG laser with an optimum value of applied frequency can be utilized as an effective technique to improve the biological characteristics.
钛合金由于其良好的耐腐蚀性、高强度和优异的生物响应而被广泛应用于矫形设备中。植入物表面与宿主组织的直接接触导致表面特性（如表面形貌）对生物响应有显著影响。本研究旨在探讨脉冲 Nd-YAG 激光频率对 Ti6Al4V 合金表面形貌的影响及其在保持其他激光参数不变的情况下对提高生物相容性的影响。所施加的频率范围从 1 到 20 Hz。表面粗糙度范围在 452nm 到 3.37μm 之间。对未经处理的样品和具有最高和最低平均表面粗糙度参数的样品进行了进一步分析。使用表面粗糙度测试仪、扫描电子显微镜 (SEM) 和原子力显微镜 (AFM) 对样品进行了表征。激光处理过程中高的熔化和凝固速率导致马氏体的形成，从而使硬度提高 12-25%。此外，还进行了体外研究，使用 MG-63 成骨样细胞。对 3 个培养时间的细胞活力、细胞形态和细胞扩展面积进行了分析，结果表明具有最高平均表面粗糙度参数的样品更具生物相容性。10Hz 的频率被发现是最佳参数，它导致了最高的表面粗糙度，从而提高了生物相容性。总之，具有最佳施加频率值的脉冲 Nd-YAG 激光可以作为一种有效的技术来改善生物特性。
