THE EFFECT OF POST-CURING CHEMICAL-CHANGES ON THE MECHANICAL-PROPERTIES OF ACRYLIC BONE-CEMENT

Total joint replacement is a procedure which gives pain relief and ren ewed mobility to over 50 000 people each year in the UK alone. While o ffering new hope to many of these people, approximately 10% of these p rostheses fail within 10 years. It is thought that cement fracture cou ld be one cause of the failure of the implant. This study was primaril y concerned with the effect of storage environment and time period on the work of fracture of Simplex P bone cement. It was found that the s torage conditions had a significant influence on the work of fracture of bone cement. In particular, storage at body temperatures embrittled the cement, while storage in fluid media had a plasticizing effect. T hese trends were related to post-curing chemical changes within the ce ment mass, specifically the absorption of low molecular mass species f rom the storage environments, and the leaching of residual monomer fro m the cement.