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; Ceramic and Composite Materials Research Group (CERMAT), Federal University of Santa Catarina (UFSC), 88040-900, Florianopolis, SC, Brazil.
J Mech Behav Biomed Mater. 2020 Dec;112:104049. doi: 10.1016/j.jmbbm.2020.104049. Epub 2020 Aug 26.
The aim of this study was to develop a novel design for implants surface functionalization through the production of HAp-coated zirconia structured surfaces by means of hybrid laser technique. The HAp-rich structured surfaces were designed to avoid hydroxyapatite (HAp) coating detachment from the zirconia surface during implant insertion, thus guaranteeing an effective osseointegration.
The functionalization process of zirconia surface started by creating micro-textures using a Nd:YAG laser and subsequent deposition of a HAp coating on the designated locations by dip-coating process. Afterwards, a CO laser was used to sinter the HAp coating. The potential of the HAp-coated zirconia structured surfaces was inspected concerning HAp bioactivity preservation, surface wettability, HAp coating adhesion to the textured surfaces and mechanical resistance of zirconia, as assessed by different approaches.
The functionalized surfaces exhibited a superhydrophilic behavior (2.30 ± 0.81°) and the remaining results showed that through the hybrid strategy, it is possible to maintain the HAp bioactivity as well as promote a strong adhesion of HAp coating to the textured surfaces even after high energy ultrasonic cavitation tests and friction tests against bovine bone. It was also verified that the flexural strength of zirconia (503 ± 24 MPa) fulfills the strict requirements of the ISO 13356:2008 standard and as such is expectable to be enough for biomedical applications.
The promising results of this study indicate that the proposed surface design can open the window for manufacturing zirconia-based implants with improved bioactivity required for an effective osseointegration as it avoids the coating detachment problem during the implant insertion.
本研究旨在通过混合激光技术生产 HAp 涂层氧化锆结构表面，开发一种新型植入物表面功能化设计。设计富含 HAp 的结构化表面是为了避免羟基磷灰石（HAp）涂层在植入物插入过程中从氧化锆表面脱落，从而保证有效的骨整合。
氧化锆表面的功能化过程首先通过 Nd:YAG 激光创建微纹理，然后通过浸涂工艺在指定位置沉积 HAp 涂层。随后，使用 CO 激光对 HAp 涂层进行烧结。通过不同的方法评估 HAp 涂层氧化锆结构化表面的潜在应用，包括 HAp 生物活性的保持、表面润湿性、HAp 涂层与纹理表面的附着力以及氧化锆的机械强度。
功能化表面表现出超亲水性（2.30±0.81°），其余结果表明，通过混合策略，可以保持 HAp 的生物活性，并在高能超声空化试验和与牛骨的摩擦试验后，促进 HAp 涂层与纹理表面的牢固附着。还验证了氧化锆的抗弯强度（503±24 MPa）满足 ISO 13356:2008 标准的严格要求，因此有望满足生物医学应用的要求。
本研究的有前景的结果表明，所提出的表面设计可以为制造具有改善的生物活性的氧化锆基植入物开辟新的途径，这是因为它可以避免在植入物插入过程中出现涂层脱落的问题，从而实现有效的骨整合。
