Zinc- and strontium- co-incorporated nanorods on titanium surfaces with favorable material property, osteogenesis, and enhanced antibacterial activity.

Early infection and peri-implantitis after implant restoration are major reasons for dental implant failure. Implant-associated infections are majorly attributed to biofilm formation. In this study, co-incorporated zinc- (Zn-) and strontium- (Sr-) nanorod coating on sandblasted and acid-etched (SLA) titanium (SLA-Zn/Sr) was fabricated by hydrothermal synthesis. It was aimed at promoting osteogenesis while inhibiting biofilm formation. The nanorod-like particles (φ 30-50 nm) were found to be evenly formed on SLA-Zn/Sr (Zn: 1.49 ± 0.16 wt%; Sr: 21.69 ± 2.74 wt%) that was composed of well-crystallized ZnTiO and SrTiO phases. With a sufficient interface bonding strength (42.00 ± 3.00 MPa), SLA-Zn/Sr enhanced the corrosion resistance property of titanium. Besides, SLA-Zn/Sr promoted the cellular initial adhesion, proliferation and osteogenic differentiation of rBMSCs in vitro while inhibiting the adhesion of Staphylococcus aureus and Porphyromonas gingivalis . In addition, through down-regulating icaA gene expression, this novel surface reduced the secretion of polysaccharide intercellular adhesion (reduced by 87.9% compared to SLActive) to suppress the S. aureus biofilm formation. We, therefore, propose a new chemical modification on titanium for multifunctional implant material development. Due to the Zn/Sr co-doping in coating, material properties, early osteogenic effect and antibacterial ability of titanium can be simultaneously enhanced, which has the potential to be applied in dental implantation in the future.