The mechanical and biological performance of zinc-containing micro-arc oxidation film on titanium implant

Abstract

Titanium is extensively utilized in orthopedic and dental implants within contemporary medicine; however, shortcomings in its ability to resist bacterial infection and promote osseointegration often result in surgical failures. To address these shortcomings, this study prepared ceramic oxide films with varying zinc concentrations on TA4 substrates through one-step microarc oxidation. The microstructure, elemental composition, chemical characteristics, and corrosion resistance of the coatings were thoroughly investigated. The antimicrobial activity and biocompatibility of the films were assessed using antimicrobial tests and hydroxyapatite induction tests. The results indicate that the films exhibit a distinctive "volcano-like" porous morphology, primarily composed of anatase, rutile, and titanium phases. Notably, the incorporation of zinc into the electrolyte did not significantly alter the microstructure or physicochemical performance of the films. In vitro antimicrobial tests demonstrated that the incorporation of zinc significantly improved the antimicrobial performance of the films. Specifically, the antimicrobial activity of Ti-0.05Zn, Ti-0.1Zn, and Ti-0.25Zn against Staphylococcus aureus was measured at 25.5 %, 60.3 %, and 75.5 %, respectively. Additionally, the antimicrobial activity of the films against Porphyromonas gingivalis was recorded at 18.3 %, 51.7 %, and 92.8 %, respectively. Furthermore, the antimicrobial performance of the zinc-containing films remained relatively stable after 7 days of immersion in simulated body fluids, with hydroxyapatite particles forming on the surface, indicating that the films possess a degree of long-term antimicrobial capacity and exhibit favorable biocompatibility.