Effects of Programmed Local Delivery from a Micro Nano-Hierarchical Surface on Titanium Implant on Infection Clearance and Osteogenic Induction in an Infected Bone Defect

BackgroundFor dental implants, early infection and peri-implantitis after implant restoration are major reasons for implant failure 1 .Plaque biofilm formation is the initiator for implant-related infection 2 .Therefore, it's urgent to develop a new antibacterial implant materials or treatment methods.It is found that nanostructured titanium surface can resist bacterial adherence and promote bactericidal capability 3 .Zinc (Zn) not only exhibits excellent antibacterial behavior with broad spectrum and limits drug-resistance bacteria induction, but also is active in osteogenesis 4 .Strontium (Sr) has various effects of improving immunologic reaction, promoting osteogenesis and inhibiting osteoclastic differentiation 4 .Aim In this study, Sr-and Zn-incorporated micro/nano-structured titanium surface with nanorods (MNT-Sr/Zn) was fabricated by a two-step hydrothermal process, aiming to improve osseointegration and reduce implant failure caused by implant-related infection and broaden new ideas for the future research on the antibacterial properties of biological materials. Materials & MethodsThe Mod Ti surfaces were used as a control.The of different surfaces was detected by a field emission scanning electron microscope (FE-SEM) equipped with energy dispersive spectra (EDS) detector.Meanwhile, Staphylococcus aureus (S. aureus) was selected to evaluate antibacterial properties through Live/Dead Staining and watching the adhesive bacterial morphology under FE-SEM.What's more, rat bone marrow-derived mesenchymal stem cells (rBMSCs) were cultured on the surfaces to detect their early osteogenic properties, like the alkaline phosphatase(ALP) activity and the osteogenesis related genes.