New Antimicrobial Biomaterials for the Reconstruction of Craniofacial Bone Defects

Reconstructive bone surgery of the head and neck could prove challenging in terms of postoperative healing and recovery. Fighting infection during the healing period is one of the critical factors of the long-term survival of an implant. The aim of the study was to develop an innovative composition suitable for an antibacterial craniofacial implant that should have the capacity to continuously and constantly release the amount of gentamicin necessary to prevent the post-surgical infections. For this purpose, a series of composite materials based on dimethacrylic monomers, hydroxyapatite and ZrO2, with (series B) or without the addition of polymethyl methacrylate (series A), reinforced with woven E-glass fibers (FRC) were obtained using the laminate lay-up process. Gentamicin was included in all FRC sample matrices to confer an antimicrobial effect. The results show that after extraction of the residual monomers from the FRC samples in different solvents (chloroform, acetone and ethyl alcohol), the cumulative amount of released gentamicin after 12 days was between 7.05–11.38 mg for A samples and 11.21–14.52 mg for B samples. The microbiological protocol showed that gentamicin induces a two weeks-lasting antimicrobial effect maintained over the minimal inhibitory concentration for P. aeruginosa and S. aureus.