Study On The Function And Stability Of Grafting Chlorhexidine Onto Tannic Acid Complexing Calcium Chloride Coating On Titanium Surface

Purpose and Background: Dental implants have become an indispensable replacement for missing teeth because of their stability and lasting function.However,implant recipients are at a high risk of serious complications,including the incidence of implant-related infections.There is an urgent need to develop effective strategies to reduce the risk of implant-related infections and their potentially life-threatening complications.Although titanium has good biocompatibility and mechanical properties,due to its lack of antibacterial properties,the surface of the implant is prone to bacterial infection leading to peri-implantitis,which ultimately leads to the loss of the bone tissue interface between the implant and the implant.Polyphenols exist widely and have many functions.In recent years,based on the general adhesion properties of phenolic molecules,metallic phenolic network(MPN)has become a widely used surface modifier.It can combine chlorhexidine with polyphenols to make chlorhexidine grafted onto the surface of titanium sheet to play antibacterial function.Methods: Commercial titanium plate after grinding,smooth titanium plate as control group,grafted with different concentrations of chlorhexidine.The composition of the elements was analyzed by X-ray photoelectron spectroscopy.The hydrophilicity was analyzed by contact Angle measuring instrument,the reaction stability was analyzed by Zeta potential test,and the antibacterial properties were analyzed by staphylococcus aureus smear counting method,bacteriostatic ring method and increment method.Methylthiazolyl tetrazolium method and fluorescence microscope were used to observe the cell activity of 1d and 3d culture,and the stability of the coating was measured after soaking for 1,4,7,14,30 and 60 days.Results: After the complexation of tannic acid and calcium,the percentage of C and Ca atoms on the surface of titanium increased obviously,the contact Angle decreased,and the Zeta potential value decreased.After the grafting of chlorhexidine,the contact Angle increased,no colonies were found on the bacterial liquid coating plate,the inhibition ring was transparent,and the bacterial proliferation OD was 0.06.There was no significant difference in cell activity between the chlorhexidine group and the control group at 1 and 3 days of cell culture,a large number of cells were attached to the surface of titanium in chlorhexidine group,and the cell morphology was good.After soaking for 1,4,7,14,30,60 days,the antibacterial ring,bacterial coating method and increment method were used to analyze the antibacterial activity of the product.Conclusions: The grafting of chlorhexidine onto tannic acid and calcium chloride on titanium surface has good biocompatibility and excellent antibacterial and bacteriostatic ability,and has lasting stability.