Surface modification of additively manufactured metallic biomaterials with active antipathogenic properties

Bacterial infection is one of the most common complications following the implantation of biomaterials and can lead to aseptic loosening, prosthesis failure, and even morbidity or mortality. Some physicochemical surface properties of metallic implants such as surface topography, roughness, pore size, and degree of porosity, play key roles in bone formation. However, highly porous and roughened surfaces result in weaker mechanical properties and more bacterial adhesion. Due to existing complications in removing bacterial biofilms, more attention is needed to produce porous and/or rough additively manufactured materials that exhibit high biocompatibility and antimicrobial efficacy. The rough surfaces generated by additive manufacturing technologies require researchers to discover methods for biofilm removal via the incorporation of additional biofunctionalities to reduce the rate of bacterial colonization of implants. Furthermore, complex 3D-printed structures fabricated by additive manufacturing methods possess larger surface areas and thus are more susceptible to bacterial infection. This necessitates the development of non-pharmacological techniques to reduce the danger of bacterial colonization. The current review provides insight into the formation of pathogens on the surfaces of additively manufactured metallic biomaterials and discusses active antipathogenic surface modifications to inhibit or control infection.