Innovative PVD Zr–Ti–Ag Thin-Film Metallic Glasses for Dental Applications: Effect of the Silver Content on Antibacterial and Biocompatible Behaviors

High Resolution Image Download MS PowerPoint Slide Zr–Ti based thin-film metallic glasses (TFMGs) constitute promising candidates for biomedical applications. Expected surfaces that are eligible for use inside the body have to gather a high biocompatibility, while preventing bacterial colonization. The objective of this work is to investigate potentialities opened by the innovative ternary Zr–Ti–Ag system. Films were deposited by magnetron cosputtering from independent targets, allowing a wide silver enrichment (10–41 at % Ag). Films were studied regarding their microstructural, mechanical, physicochemical, and biological properties. These properties were discussed in light of the films’ composition. This study established that the structure of the films was strongly influenced by their silver content. The expected amorphous structure was obtained between 20 and 36 at % Ag, for which mechanical properties are high, and compatible with a potential biomedical application. Surface is then very smooth, with presence of dispersed micrometric crystallized islets. Evolution of the surface wettability was found to be primarily governed by the film morphology rather than by its chemical composition. Biologically, a pronounced antibacterial activity against both E. coli and S. gordonii was recorded from 25 at % Ag. Such an antibacterial effect was assigned to silver, as demonstrated by tests carried out with synthetic ions-released solutions. Besides, these films also have evidenced a good cytocompatibility toward gingival fibroblasts. These results highlight the key role of composition-controlled microstructure of Zr–Ti–Ag TFMGs, and demonstrate their potential as antibacterial and biocompatible coatings for dental implant applications.