Study On The Properties Of Light-Cured Resin Composites Modified With Graphene Oxide

BackgroundLight-cured resin is widely used in the field of dentistry,but its mechanical and antibacterial properties still need to be improved,which limits its application to a certain extent.By incorporating nano-fillers into photo-cured resin,it is expected to break through the limitations and improve the comprehensive properties of the light-cured resin.Recently,it has been proved that after adding graphene oxide to heat-cured resin such as epoxy resin and acrylic resin,resin composites show greater comprehensive properties.For instance,its mechanical properties,corrosion resistance and thermal properties have been improved to varying degrees.However,there is no study regarding photo-cured resin incorporated with graphene oxide presently.It remains to be further studied that whether light-cured resin composite incorporated with graphene oxide shows greater properties.ObjectiveIn this study,graphene oxide was incorporated into light-cured resin(Bis-GMA)to improve the comprehensive properties of the resin composite.Here,the mechanical properties,antimicrobial-adhesive properties and cytotoxicity of light-cured resin composites incorporated with graphene oxide with different ratio were explored,and the ratio of resin composites with greatest comprehensive properties was screened out,which provided a new idea for improving the comprehensive properties of light-cured resin.Materials and methods1.In Chapter 1,the basic characterization of graphene oxide for modification was tested.2.In Chapter 2,graphene oxide was incorporated into light-cured resin with different ratio.Three-point flexural strength,hardness and contact angle of resin composites were evaluated.And with the results of cross-section morphology observation,we tried to analyzed the underlying reason and the appropriate doping ratio of graphene oxide in resin composite was optimized.3.In Chapter 3,antimicrobial-adhesive effects of the resin composite with appropriate doping ratio of graphene oxide were determined.The best suitable ratio of graphene oxide in resin composite was selected.4.In Chapter 4,we performed a preliminary evaluation of the in vitro cytotoxicity of the selected resin composite with the best suitable ratio of graphene oxide.Results1.Graphene oxide had a typical lamellar structure,which was suitable for further modification of resin composite.2.The resin composite incorporated with 0.5 wt%and 1.0 wt%graphene oxide had great mechanical properties and hydrophilicity.Among them,the resin composite incorporated with 1.0 wt%graphene oxide had better properties,its three-point bending strength was 73.6976 ±2.53496 MPa,Shore A hardness was 82.680 ±0.9418 HD,surface contact angle was 68.300±0.8860°.3.The resin composite incorporated with 0.5 wt%and 1.0 wt%graphene oxide showed good anti-adhesive effects.Among them,composite resin incorporated with 1.0 wt%graphene oxide had the least number of bacteria adhered to the surface,which was only 50.38%of that of the control group.4.The resin composites incorporated with 1.0 wt%graphene oxide had the best comprehensive properties and had no obvious cytotoxicity to the human gingival fibroblasts,and the cytotoxicity grade was 0 grade in vitro.ConclusionAfter incorporating 1.0 wt%graphene oxide into the light-cured resin,the mechanical properties and anti-bacterial adhesion properties of the resin were successfully improved,thereby obtaining a potential dental composite material.