Laser-induced periodic surface structures on TiAl6V4 surfaces by picosecond laser processing for dental abutments

Abstract

Although Titanium and its alloys are generally used for the manufacturing of dental implant abutments, they are typically prone to bacterial infection, due to their implantation in the transgingival region. In close contact with the soft surrounding tissue, the surface may be functionalized in order to improve connective tissue cells adhesion while preventing bacterial penetration at the interface. Ultrafast laser processing of dental implants has demonstrated the potential to obtain unique surface features, down to the nanoscale. With this study, we introduce the possibility to generate laser-induced periodic surface structures (LIPSS) by picosecond laser processing, with periodicity of about 500 nm on large-scale surfaces, in a contamination-free approach. By changing the applied laser dose, different surface coloring of TiAl6V4 samples is obtained due to a gradual surface oxidation, as revealed by depth-profile compositional analyses. In the same time, an increase of the irradiation dose induced the formation of thicker oxide layers, the oxygen content increasing up to ten times. The response of human mesenchymal stem cells (hMSCs) in contact with laser processed surfaces was evaluated to assess samples cytocompatibility. It was demonstrated that large-scale, uniform LIPSS distributed on whole TiAl6V4 surface are beneficial to hMSCs viability and proliferation.