The effect on the fatigue strength of bone cement of adding sodium fluoride

New bone cements that include several additives are currently being investi gated and tested. One such additive is sodium fluoride (NaF), which promote s bone formation, facilitating implant integration and success. The influen ce of NaF on the fatigue performance of the cement as used in biomedical ap plications was tested in this paper. In fact fatigue failure of the cement mantle is a major factor limiting the longevity of a cemented implant. An experimental bone cement with added NaF (12 wt %) was investigated. The fatigue strength of the novel bone cement was evaluated in comparison with the cement without additives; fatigue tests were conducted according to cur rent standards. The load levels were arranged based on a validated, statist ically based optimization algorithm. The curve of stress against number of load cycles and the endurance limit were obtained and compared for both for mulations. The results showed that the addition of NaF (12 wt %) to polymet hylmethacrylate (PMMA) bone cement does not affect the fatigue resistance o f the material. Sodium fluoride can safely be added to the bone cement with out altering the fatigue performance of the PMMA bone cement.