Center for Micro-Electro Mechanical Systems (CMEMS-UMinho), University of Minho, Campus de Azurém, 4800-058, Guimarães, Portugal.
Center for Micro-Electro Mechanical Systems (CMEMS-UMinho), University of Minho, Campus de Azurém, 4800-058, Guimarães, Portugal.
Mater Sci Eng C Mater Biol Appl. 2020 Mar;108:110390. doi: 10.1016/j.msec.2019.110390. Epub 2019 Nov 7.
The development of new surface designs to enhance the integration process between surgically placed implants and biological tissues remains a challenge for the scientific community. In this way and trying to overcome this issue, in this work, laser technology was explored to produce novel textures on the surface of green zirconia compacts produced by cold pressing technique. Two strategies regarding line design (8 and 16 lines design) and different laser parameters (laser power and number of laser passages) were explored to assess their influence on geometry and depth of created textures. The produced textures were evaluated with Scanning Electron Microscopy (SEM) and it was observed that well-defined textured surfaces with regular geometric features (cavities or pillars) were obtained by laser combining different strategies lines design and parameters. The potential of proposed textures was also evaluated regarding surface wettability, friction performance (static and dynamic coefficient of friction evolution) against bone, aging resistance and flexural strength. Results demonstrated that all the produced textures display a super hydrophilic or hydrophilic behavior. Regarding the friction behavior, it was experimentally observed a high initial static coefficient of friction (COF) for all produced textures. Concerning the aging resistance, all the textured surfaces revealed a low monoclinic content, less than 25% after 5 h of hydrothermal aging. The flexural strength results showed that the mechanical resistance of zirconia was not significantly compromised with the laser action. Based on the obtained results, it is possible to prove that the processing route used for manufacturing the new and different surface designs (cold pressing technique followed by laser texturing) showed to be particularly effective for the production of zirconia implants with customized surface designs according to the properties required in a specific application. These new surface designs besides to enhance the surface wettability and also to improve the fixation at the initial moment of the implantation, do not significantly compromise the resistance to aging and the mechanical performance of zirconia. Hence, a positive impact on the long-term performance of the zirconia implants may be expected with the proposed novel laser textured surface designs.
开发新的表面设计以增强手术植入物与生物组织之间的整合过程仍然是科学界面临的挑战。为了实现这一目标并克服这一问题，本工作探索了激光技术在通过冷压技术制备的绿色氧化锆压坯表面上产生新颖纹理的应用。探索了两种线设计策略（8 线和 16 线设计）和不同的激光参数（激光功率和激光通过次数），以评估它们对线的几何形状和深度的影响。使用扫描电子显微镜（SEM）评估所产生的纹理，观察到通过激光结合不同的线设计策略和参数，可以获得具有规则几何特征（腔或柱）的定义良好的纹理表面。还评估了所提出纹理的潜在用途，包括表面润湿性、与骨骼的摩擦性能（静态和动态摩擦系数演变）、耐老化性和弯曲强度。结果表明，所有产生的纹理都表现出超亲水或亲水的特性。关于摩擦行为，实验观察到所有产生的纹理的初始静态摩擦系数（COF）都很高。关于耐老化性，所有纹理表面的单斜相含量都很低，在 5 小时水热老化后都低于 25%。弯曲强度结果表明，激光处理并没有显著降低氧化锆的机械强度。根据获得的结果，可以证明用于制造新的和不同表面设计的加工路线（冷压技术 followed by laser texturing）特别有效，可根据特定应用所需的特性生产具有定制表面设计的氧化锆植入物。这些新的表面设计除了提高表面润湿性外，还可以在植入物初始固定阶段提高固定效果，而不会显著降低氧化锆的耐老化性和机械性能。因此，预计所提出的新型激光纹理表面设计会对氧化锆植入物的长期性能产生积极影响。
