Study On Hydrogen Peroxide Modified SLA Pure Titanium Surface To Promote Implant Osseointegration

Objective:To evaluate the effectiveness of hydrogen peroxide modified SLA pure titanium surface in promoting implant osseointegration,and to explore its mechanism of promoting osseointegration.Methods:The surface of traditional large particle sand blasting and acid etching（SLA）pure titanium was nano modified with hydrogen peroxide（H₂O₂）.It was divided into SLA group,h1SLA group（H₂O₂treatment for 1 hour）and h2SLA group（H₂O₂treatment for 2 hours）.The differences of physical and chemical properties before and after treatment were compared by scanning electron microscope（SEM）and contact angle test.By observing the adhesion,spreading,proliferation and osteogenic differentiation of rat bone marrow mesenchymal stem cells（r BMSCs）on different treated surfaces,the difference of biological activity of each surface was analyzed.After selecting the relatively optimal group treated with H₂O₂,the osteogenic difference in beagle dogs was further analyzed by taking SLA surface as the control.Finally,two groups of r BMSCs on titanium surface were sequenced to analyze the mechanism of promoting osteogenic differentiation.Results:Micro nano composite structure appears on the surface of SLA modified by H₂O₂,and the surface hydrophilicity is greatly improved.The results of biological experiments showed that the surface of H₂O₂modified SLA was more conducive to the adhesion,spreading,proliferation and osteogenic differentiation of r BMSCs than that of SLA group,and the effect of promoting bone differentiation of h1SLA group was better.Animal experiments further verified the superior osteogenic properties of h1SLA group.Transcriptome sequencing showed that the expression of genes positively related to osteogenesis was significantly up-regulated in h1SLA group.KEGG analysis showed that PI3K-AKT pathway was significantly activated.This suggests that the mechanism of promoting bone formation in h1SLA group may be closely related to it.Conclusion:The surface of SLA pure titanium modified by H₂O₂endows it with micro nano composite structure and high hydrophilicity,and significantly promotes the adhesion,spreading,proliferation and osteogenic differentiation of r BMSCs.Animal experiments and transcriptome sequencing results further verified the best osteogenic performance of h1SLA group,but its mechanism of promoting bone formation remains to be verified.