Influence of changes in the composition of an acrylic bone cement on its polymerization kinetics

It has been suggested in the literature that a lower polymerization rate of an acrylic bone cement is favorable for the in vivo longevity of a cemented arthroplasty. The present work was a study of the influence of three changes in the composition of an acrylic bone cement (when taken separately) on the cement polymerization rate at 37°C (assumed to be the temperature in the bone bed during a cemented arthroplasty) [k′]. The changes were the amount of copolymer as a proportion of the total powder weight (in cements in which there is a copolymer in the powder), the amount of DMPT as a proportion of the total volume of the liquid monomer, and the accelerator, k′ was calculated using values of the activation energy and the frequency factor (assuming the polymerization reaction is Arrhenius in nature) that were computed from measurements made using the nonisothermal mode of differential scanning calorimetry. Statistical analysis (one-way ANOVA, with Bonferroni correction, and factorial ANOVA) of the k′ values showed that the change in accelerator had a significant influence on k′. The importance of this finding, together with results from two relevant literature reports, is discussed within the context of the use of modified bone cements in cemented arthroplasties. © 2006 Wiley Periodicals, Inc