Composites of poly(methyl methacrylate) with hybrid fillers (micro/nanohydroxyapatite): Mechanical, setting properties, bioactivity and cytotoxicity in vitro

Novel composites of poly(methyl methacrylate) with silanized micro and nanohydroxyapatite (HA) particles were prepared. Coralina^® HA was the MicroHA filler and synthetic NanoHA was the reinforcement. The influence of the total inorganic content and the proportion of micro‐ to NanoHA on the setting properties (i.e., setting time and peak polymerization temperature), compressive strength, and in vitro bioactivity in simulated body fluid (SBF) was analyzed. The novel composites exhibited appropriate handling properties. Compressive strength ranged between 71.30 ± 0.04 and 80.0 ± 2.4 MPa. The peak polymerization temperatures varied from 44.5 ± 0.5 to 50.8 ± 1.8°C, and thus complying with the ISO 5833 standard. The composites exhibited excellent calcium phosphate deposition in SBF and those with 30 wt% inorganic content showed no cytotoxicity on L929 fibroblastic cells. These results encourage further testing of these novel composites for potential future use in human health applications. POLYM. COMPOS., 34:1927–1937, 2013. © 2013 Society of Plastics Engineers