Enhanced Biological Properties And Safety In Clinical Application Of Pure Mg By Applying Ag-incorporated FHACoating

Objective:The aim of this study is to investigate the effect of Ag-incorporated FHA(Ag-FHA)coating on both antibacterial property and osteogenesis of magnesium.The effect of Ag-FHA coating on the corrosion behavior of pure magnesium when co-implanted with heterogeneous metals was also investigated.Methods:Methicillin-resistant staphylococcus aureus(MRSA)were used to establish acute bone infection rat model.The antibacterial property and osteogenesis of Mg was investigated both in vitro and in vivo.The Ag-FHA coating was prepared on the surface of magnesium by electrodeposition and immersion method.The material properties of coatings were investigated.Ti screw and Mg screw or Ag-FHA/Mg screw were co-implanted into Sprague-Dawley rat's femur.The corrosion behavior of Mg screw and Ag-FHA/Mg screw were analyzed.Results:Although excellent antibacterial property of magnesium was observed in vitro,in the in vivo test,the antibacterial rate of magnesium decreased dramatically.The results of microbial experiments demonstrated enhanced antibacterial rate of Ag-FHA/Mg than that of Mg.Moreover,osteogenesis of pure Mg is also enhanced by applying Ag-FHA coating.When co-implanted with Ti screw,the Mg screw demonstrated accelerated corrosion rate even without direct contact.The Ag-FHA coating can help reduce the degradation of magnesium.Conclusion:Ag-FHA coating could effectively enhance the antibacterial property as well as osteogenesis of pure Mg.When Mg is co-implanted with heterogeneous metals,the Ag-FHA coating could protect Mg from accelerated corrosion.Therefore,Ag-FHA coating might be an alternative in the application of surface modification for biodegradable Mg.