Antibacterial Structure Design of Porous Ti6Al4V by 3D Printing and Anodic Oxidation

Abstract

Titanium alloy Ti6Al4V is a commonly used bone implant material, primarily prepared as a porous material to better match the elastic modulus of human bone. However, titanium alloy is biologically inert and does not have antibacterial properties. At the same time, the porous structure with a large specific surface area also increases the risk of infection, leading to surgical failure. In this paper, we prepared three porous samples with different porosities of 60%, 75%, and 85%, respectively (for short, 3D-60, 3D-75, and 3D-85) using 3D printing technology and clarified the mechanical properties. Through tensile experiments, when the porosity was 60%, the compressive modulus was within the elastic modulus of human bone. Anodic oxidation technology carried out the surface modification of a 3D-printed porous titanium alloy with 60% porosity. Through change, the different voltages and times on the TiO2 oxide layer on the 3D-printed porous titanium alloy are different, and it reveals the growth mechanism of the TiO2 oxide layer on a 3D-printed unique titanium alloy. The surface hydrophilic and antibacterial properties of 3D-printed porous titanium alloy were significantly improved after modification by anodic oxidation.

Preparation of Ag@3D‐TiO2 Scaffolds and Determination of its Antimicrobial Properties and Osteogenesis‐promoting Ability

“…According to previous studies, the porous Ti alloy with 60% porosity has good mechanical properties, the maximum compressive strength is about 112 MPa, and matches well with natural bone. 15 Therefore, we chose a 3D printed porous Ti alloy scaffold with 60% porosity (filament diameter of 5.0, pore size of approximately 350 μm) for the subsequent modification study.…”

“…For our antimicrobial studies, we selected the gram‐positive bacterium S. aureus , 15 which was initially incubated in 5 mL of L.B. medium.…”

“…According to previous studies, building specific nanostructure arrays on the implant surface can prevent the production of bacteria, 13 , 14 such as the porous Ti alloy surface is formed by secondary anodization to form an oxidized film that is biologically active and inhibits the production of bacteria to a certain extent. 15 , 16 , 17 However, for orthopedic implant materials, it is important to exhibit strong antimicrobial properties, good biocompatibility, and promote osteogenic differentiation in addition to inhibiting bacteria. Therefore, the biomedical properties of Ti alloys can be improved by modifying the surface with coatings.…”

Tribocorrosion and Surface Protection Technology of Titanium Alloys: A Review

“…Porous titanium alloy materials have an elastic modulus matching that of human bone tissue, effectively solving the elastic mismatch between implants and human bone [ 113 , 114 , 115 , 116 , 117 , 118 , 119 ]. Recently, additive manufacturing technology has been used to prepare porous titanium alloy materials [ 120 , 121 , 122 , 123 , 124 , 125 ]. This method uses tool software such as 3DXpert (France) and Simulate Additive (Sweden) to design the absorbent structure.…”

Regulation Mechanism of Special Functional Groups Contained in Polymer Molecular Chains on the Tribological Properties of Modified Ti6Al4V

“…Titanium alloys have high corrosion resistance, a low elastic modulus and good biocompatibility, and they have become the preferred choice of human implant materials [1][2][3][4]. However, these outstanding properties of titanium alloys cannot fully meet the requirements for clinical applications, such as extremely low friction, which is needed at tribological interfaces of living organisms.…”