Titania Nanotube Architectures Synthesized on 3D-Printed Ti-6Al-4V Implant and Assessing Vancomycin Release Protocols

The aim of this study is to synthesize Titania nanotubes (TNTs) on the 3D-printed Ti-6Al-4V surface and investigate the loading of antibacterial vancomycin drug dose of 200 ppm for local drug treatment application for 24 h. The antibacterial drug release from synthesized nanotubes evaluated via the chemical surface measurement and the linear fitting of Korsmeyer–Peppas model was also assessed. The TNTs were synthesized on the Ti-6Al-4V surface through the anodization process at different anodization time. The TNTs morphology was characterized using field emission scanning electron microscope (FESEM). The wettability and the chemical composition of the Ti-6Al-4V surface and the TNTs were assessed using the contact angle meter, Fourier transform infrared spectrophotometer (FTIR) and the X-ray photoelectron spectroscopy (XPS). The vancomycin of 200 ppm release behavior under controlled atmosphere was measured by the high-performance liquid chromatography (HPLC) and hence, the position for retention time at 2.5 min was ascertained. The FESEM analysis confirmed the formation of nanostructured TNTs with vertically oriented, closely packed, smooth and unperforated walls. The maximum cumulative vancomycin release of 34.7% (69.5 ppm) was recorded at 24 h. The wetting angle of both Ti-6Al-4V implant and the TNTs were found below 90 degrees. This confirmed their excellent wettability.

Controlled release of the drug for osteoporosis from the surface of titanium implants coated with calcium titanate

The most popular drugs used to prevent osteoporosis that causes low mineral density and weakened microstructure of bones are bisphosphonates. Bisphosphonates can be administered in several ways, but each delivery method has drawbacks. Due to this, new methods of their delivery are being sought. Titanium implants coated with calcium titanate were prepared in this work as carriers for bisphosphonates. Such a modification has been proposed in order to improve the therapeutic properties of the implant. Slow release of the drug at a constant level will positively affect the recovery process and osteointegration. Furthermore, the drug will be slowly released very close to the area affected by osteoporosis. These studies were confirmed, using a variety of methods: EDS and XPS (to examine surface modification and drug sorption), Raman mapping (to proof the presence of the drug on the entire surface of the material) and UV-VIS spectroscopy (to determine bisphosphonate sorption and release profile). It was proved that the active substance (sorbed on the implant) could be completely released upon contact with body fluids within a month. The obtained results will allow for the production of endoprostheses dedicated to patients with osteoporosis in the future.

Mechanical, Electrochemical, and Osteoblastic Properties of Gradient Tantalum Coatings on Ti6Al4V by Prepared Plasma Alloying Technique

Plasma alloying technique capable of producing metallic coatings with metallurgical bonding has attracted much attention in dental and orthopedic fields. In this study, the effects of temperature and time of plasma tantalum (Ta) alloying technique on the mechanical, electrochemical, and osteoblastic properties of Ta coatings were systematically investigated. Ta coatings prepared at 800 °C possess better interfacial strengths than those prepared at 750 and 850 °C, and the interfacial strength increases with prolonged alloying time (30–120 min). At 800 °C, however, the increased proportion of the soft Ta deposition layer with alloying time in the whole coating impairs the surface mechanical properties of the entire coating, as convinced by decreased microhardness and wear resistance. Moreover, Ta coatings exhibit better corrosion resistance than the Ti6Al4V substrate in Dulbecco’s modified Eagle medium. The enhanced adhesion and extracellular matrix mineralization level of osteoblasts demonstrate the better cytocompatibility and osteogenic activity of the Ta coating. Ta30 (Ta coating prepared at 800 °C for 30 min) exhibits excellent mechanical, electrochemical, and osteoblastic behaviors and is promising in biomedical applications.

Neodymium-decorated graphene oxide as a corrosion barrier layer on Ti6Al4V alloy in acidic medium

Ti6Al4V alloy is light weight and is used in construction, oil industries and airbus, automobile, and bio implant materials. The native oxide layers of the alloy are not stable at high temperatures and strong mineral acid environments. The conventional epoxy-based layers are porous and the alloy finally fails in the harsh environment in the long term. Therefore, the carbon-based functional materials are being proposed as coating materials to overcome the alloy degradation. In the present contribution, we have used the neodymium-decorated graphene oxide as the corrosion inhibiting barrier for the Ti6Al4V alloy. As a novelty, we found that the few-layer graphene decorated with neodymium acts as a self-cleaning coating. The Nd-decorated graphene oxide were studied by XRD, TEM, FESEM, FTIR, UV, and Raman spectroscopy. The corrosion inhibition efficiency was studied by electrochemical methods.

Corrosion Resistance of 2060 Aluminum⁻Lithium Alloy LBW Welds Filled with Al-5.6Cu Wire

Alloy sheets of type 2060 aluminum⁻lithium were welded by laser beam welding (LBW) filled with ER2319 Al-5.6Cu wire. Microstructural observations showed the uneven distribution of columnar grains, equiaxed grains and equiaxed dendrite grains in the weld. The θ'(Al₂Cu) phase and other phases precipitated in the weld. The θ'(Al₂Cu) phase centrally distributed at the grain boundaries. During the immersion corrosion, the pitting corrosion first occurred and then gradually expanded and transformed to intergranular corrosion and exfoliation corrosion. The electrochemical corrosion test showed a higher corrosion tendency of the base metal and heat-affected zone for the lower corrosion potential, but the corrosion current density of the weld was relatively larger. The segregation of Cu, Mg and other elements at the grain boundary aggravated the occurrence of intergranular corrosion.

Selective laser melted titanium alloys for hip implant applications: Surface modification with new method of polymer grafting

A significant number of hip replacements (HR) fail permanently despite the success of the medical procedure, due to wear and progressive loss of osseointegration of implants. An ideal model should consist of materials with a high resistance to wear and with good biocompatibility. This study aims to develop a new method of grafting the surface of selective laser melted (SLM) titanium alloy (Ti-6Al-4V) with poly (2-methacryloyloxyethyl phosphorylcholine) (PMPC), to improve the surface properties and biocompatibility of the implant. PMPC was grafted onto the SLM fabricated Ti-6Al-4V, applying the following three techniques; ultraviolet (UV) irradiation, thermal heating both under normal atmosphere and UV irradiation under N₂ gas atmosphere. Scanning electron microscopy (SEM), 3D optical profiler, energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR) were used to characterise the grafted surface. Results demonstrated that a continuous PMPC layer on the Ti-6Al-4V surface was achieved using the UV irradiation under N₂ gas atmosphere technique, due to the elimination of oxygen from the system. As indicated in the results, one of the advantages of this technique is the presence of phosphorylcholine, mostly on the surface, which reveals the existence of a strong chemical bond between the grafted layer (PMPC) and substrate (Ti-6Al-4V). The nano-scratch test revealed that the PMPC grafted surface improves the mechanical strength of the surface and thus, protects the underlying implant substrate from scratching under high loads.

Surface Texture-Based Surface Treatments on Ti6Al4V Titanium Alloys for Tribological and Biological Applications: A Mini Review

Surface texture (ST) has been confirmed as an effective and economical surface treatment technique that can be applied to a great range of materials and presents growing interests in various engineering fields. Ti6Al4V which is the most frequently and successfully used titanium alloy has long been restricted in tribological-related operations due to the shortcomings of low surface hardness, high friction coefficient, and poor abrasive wear resistance. Ti6Al4V has benefited from surface texture-based surface treatments over the last decade. This review begins with a brief introduction, analysis approaches, and processing methods of surface texture. The specific applications of the surface texture-based surface treatments for improving surface performance of Ti6Al4V are thoroughly reviewed from the point of view of tribology and biology.