FRACTURE-TOUGHNESS OF COMPOSITE ACRYLIC BONE CEMENTS

Composite bone cements incorporating one of four different filler particles (hydroxyapatite powder, graphite flakes or one of two types of rubber-modified acrylic particles) were made and the fracture toughness properties (K(lc)) and curing characteristics (peak curing temperature and cement extrudability while in the doughy state) assessed. The results showed that all filler types studied resulted in significant increases in fracture toughness while maintaining acceptable working and curing characteristics of the composite cements. The increase in K(lc) was related to the amount of filler incorporation. The observed dependence of the change in K(lc) on the wt% filler could be rationalized through the application of proposed mechanisms for toughening of particle-reinforced polymers.