The effect of adding 10% of barium sulphate radiopacifier on the mechanical behaviour of acrylic bone cement

Barium sulphate (BaSO4) is commonly used in bone cement as a radiopacifier. The addition of the BaSO4 to the polymeric matrix may cause a decrease in the mechanical properties of the cement. In this work, the effect of adding 10%w/w BaSO4 to a plain polymethylmethacrylate based bone cement was evaluated in terms of endurance limit, fatigue crack propagation and fracture toughness. A lower endurance limit (−13%), as well as a lower fracture toughness (−13%), was found for the radiopaque bone cement in comparison with the plain formulation. Conversely, a substantial decrease (66%) in the crack growth rate was found due to the radiopacifier addition. These are all effects that reflect the weakening of the polymeric matrix, caused by the addition of the radiopacifier.