Study On Improving Antibacterial And Osteogenic Activity Of Titanium Implants Through Cephafotaxime Sodium/Polydopamine Coating

Background: Peri-implantitis is one of the main causes of dental implant failure.At the same time,the osseointegration of three to six months after dental implantation has also limited the promotion in clinics Therefore,it is of great significance to prevent related infections around the implant and shorten the period of implant through a simple,efficient and rapid implant chairside treatment to improving the osteointegration of the implant.Objective: To solve the defects of lack of antibacterial properties on the surface of commercially available implants,and long osteointegration time of dental implants,we intend to develop a chairside modification method which is based on polydopamine/ cefotaxime sodium with antibacterial and osteointegration capabilities.Method: High-temperature water bath was used to deposite polydopamine/ cefotaxime sodium on pure titanium surfaces.Scanning electron microscope,Atomic force microscope,X-ray photoelectron spectroscopy,and static contact angle measuring instrument were used to characterize surface morphology,element composition,surface roughness,and hydrophilicity.WST-8 and the L7012 microbial fluorescent dead-living staining were used to evaluate the ability to resist Escherichia coli and Streptococcus mutans;CCK8 and cytoskeleton fluorescent labeling methods were used to evaluate the effects of samples from 1-7 days on the proliferation of human mesenchymal stem cells in vitro and cytoskeleton morphology;Alizarin red staining,Alkaline phosphatase,RT-PCR and Immunofluorescence were used to evaluate osteogenic differentiation efficiency of human mesenchymal stem cells loaded on titanium surfaces coated with polydopamine/ cefotaxime sodium,at the same time,mesenchymal stem cell medium without the addition of osteogenic induction medium was used as a control to detect the ability of the substrate to induce spontaneous differentiation.Results: The XPS results showed that N 1s and S 2p appeared on the pure titanium after reaction,and the results of AFM and SEM showed that with the extension of the water bath rotation reaction,which proved that the polydopamine/cefotaxime sodium covered the pure titanium surface successfully;The results of WST-8 and L7012 stain showed that the titanium surface modified with cefotaxime polydopamine coating had excellent antibacterial properties.Cell viability test CCK8 results confirmed that the 30 minutes reaction time of polydopamine/cefotaxime sodium would reach the best proliferation ability of mesenchymal stem cells;Alizarin red staining,alkaline phosphatase,RT-PCR and immunofluorescence results of osteogenic induction and spontaneous differentiation of mesenchymal stem cells on the surface of polydopamine/cefotaxime-modified titanium showed that the pure titanium surface loaded with cefotaxime sodium polydopamine coating in the 30 minute reaction would promote proliferation and osteogenic differentiation of human mesenchymal stem cells.Conclusion: A chairside implant modification scheme was successfully designed,which has the advantages of simple and fast modification,effectively improving the antibacterial ability around the implant,and promoting the osteogenic differentiation of mesenchymal stem cells.The 30 minute reaction time of polydopamine/ cefotaxime modified titanium has clinical application potential to promote osteointegration after implantation,and the 60 minute response time of polydopamine/ cefotaxime modified titanium has the potential for clinical application in preventing related infections around the implants.The development of the results are expected to promote chairside modification of implants clinics,reduce the incidence of Peri-implantitis,and further shorten the time of dental implantation.