Characterization and biocompatibility evaluation of a Ti@HA-GO@IL-4 bioactive composite coating for guided bone regeneration in dental implant applications.

BACKGROUND: Pure titanium and titanium alloy implants have been widely utilized in dental implantology due to their excellent biocompatibility and favorable elastic modulus. However, the inherent bioinertness of titanium-based implant surfaces often results in suboptimal osseointegration with surrounding bone tissue. Consequently, surface modification is essential to enhance the osseointegrative capacity of titanium implants. METHODS: We fabricated hydroxyapatite-graphene oxide (HA-GO) coatings via electrochemical deposition and systematically compared four distinct protein loading methods. Ultimately, we developed a hydroxyapatite-graphene oxide/interleukin-4 (Ti@HA-GO@IL-4) coating on pure titanium substrates to investigate its physicochemical properties and biocompatibility. RESULTS: The composite coating was successfully fabricated on pure titanium substrates, inducing significant surface modifications including the incorporation of bioactive functional groups, enhanced hydrophilicity, and altered surface morphology. Comparative characterization revealed that the composite coating exhibited superior hydrophilic properties, improved mechanical compatibility with bone tissue, stable Interleukin-4 (IL-4) adsorption and sustained-release behavior, as well as excellent biosafety confirmed by proliferation and adhesion assays using mouse embryo osteoblast precursor (MC3T3-E1) cells, when compared to unmodified titanium controls. CONCLUSIONS: Ti@HA-GO@IL-4 represents a composite coating material with exceptional physicochemical properties and biological performance. This material demonstrates efficient IL-4 loading capacity and sustained release characteristics, thereby effectively promoting osteogenesis. These findings provide valuable insights for developing bioactive functional materials to enhance implant osseointegration.