A Comprehensive Review on Novel Graphene‐Hydroxyapatite Nanocomposites For Potential Bioimplant Applications

Abstract The advancements in medical treatment necessitated the development of advanced bio‐implant materials for hard tissue replacement and bone regeneration. Hydroxyapatite (HA), an extreme bioresorbable material having physicochemical similarities with natural bone, seems to be a good bioimplant. Still, the ineffective mechanical properties, viz. fracture toughness, wear resistance, and tensile strength, restrict its practical utility in bioimplants. Recently, graphene‐HA nanocomposites have been explored for potential bioimplant applications ascribed to their superior biocompatibility, bioactivity, osteoconductivity, and enhanced mechanical properties. The huge surface area with a two‐dimensional sheet structure facilitates graphene's strong integration with HA, thus enhancing mechanical properties. These enhanced mechanical properties of graphene‐HA nanocomposite are chiefly attributed to the pull‐out, ridge growth, crack deflection, and grain bridging characteristics exhibited by graphene filler in the HA matrix. Further, graphene is neutral and biocompatible, thus improving the graphene‐HA nanocomposite‘s biocompatibility. These qualities made this nanocomposite a rising star among bio‐ceramic implant materials. This review presents the current scenario on the synthesis and mechanical and biological properties of graphene‐hydroxyapatite nanocomposite, which seems to be a propitious material for implants in orthopaedic applications.