New insights into the role of Al2O3 nano-supplements in mechanical performance of PMMA and PMMA/HA bone cements using nanoindentation and nanoscratch measurements.

This work was performed to investigate the mechanical and tribological properties of polymethyl methacrylate (PMMA)-based bone cement strengthened by nano-alumina (Al2O3) and nano-hydroxyapatite (HA) particles. Seven cement groups with different amounts of Al2O3 (3 and 5 wt. %) and HA (5 and 10 wt. %) nano-particles were prepared and the nanoindentation and nanoscratch tests were employed to obtain the results. Substantial improvement/reduction in mechanical properties was observed for the addition of 3 wt. % of Al2O3 /5 wt. % of Al2O3 plus 10 wt. % of HA into the PMMA matrix. The additives had almost no obvious effects on the friction of PMMA (~0.3). This research revealed that only the specific weight percent of Al2O3 (here 3 wt. %), compared to other PMMA/Al2O3 and PMMA/HA/Al2O3 cement nanocomposites, had great potential as an added component in PMMA bone cement to provide a significant increase in the mechanical properties of the cement. [ABSTRACT FROM AUTHOR]