Event Abstract Back to Event Antimicrobial and cytotoxicity analysis of zinc phosphate cement Samantha Booth1 1 University of Greenwich, Pharmaceutical, Chemical and Environmental Sciences, United Kingdom Introduction: Many clinicians and researchers understand zinc phosphate cement to be antimicrobial and biocompatible as it is used regularly in dentistry[1]. The materials’ use has declined over time however due to irritation and inflammation of the tissue surrounding the cement on implantation[2]. This study aims to characterise the antimicrobial and cytotoxicity properties of this material. Materials and Methods: MG63 osteosarcoma cells were grown in direct contact with the material for up to two weeks and in a separate study with the cement leachate for 5 days. An MTT assay, SEM, ICP-OES analysis were performed on the samples. A zone of inhibition test was carried out against S. aureus, P. aeruginosa, E. coli and S. mutans. Results and Discussion: The morphology of the MG63 cells did not alter, in comparison with the control cells and after 14 days, the cells proliferated and occupied the majority of the surface of the material. The MTT assay highlighted the ability of zinc phosphate cement leachate to sustain 76.8% viability of cells over 120 hours when compared to control cells. The ICP-OES results show negligible zinc ion release throughout the experiment that suggests the zinc is almost fully bound into the material once set. Zinc phosphate cement only presented antimicrobial activity towards E. coli, which suggests that this property could be due to another mechanism, potentially acidity, rather than the effect of zinc ions, as previously suggested. Conclusions: Zinc phosphate shows an antimicrobial effect against E. Coli and is not cytotoxic to MG63 osteosarcoma cells. The cells appear to have a similar morphology to that of the control when grown on the cement surface. Minimal zinc ions are released after 48h of incubation which indicates the antimicrobial effect is not due to zinc. Dr Arun Kotha