A comparison of the mechanical properties of Simplex, Zimmer, and Zimmer low viscosity bone cements.

Many different methods have been used to compare polymethylmethacrylate bone cements. In this paper the three currently available cements were compared in regard to dough and set times, heat of polymerization, compressive, tensile, 3 and 4 point bending strengths, fracture toughness, flexural modulus, void density distribution, and viscosity. Methods used were ASTM designated for bone cement or plastics in general whenever possible. Significant differences in set and dough times and heat of polymerization were noted. All cements were equal in compressive, tensile, and fracture toughness testing; Zimmer Regular Cement was significantly weaker (p less than 0.001) in flexural testing and had a significantly (p less than 0.001) decreased modulus of elasticity when compared to LVC and Simplex Cements. Void density distributions were not significantly different. Viscosity was shown to vary between these cements as well. This data was analysed both to determine differences between various brands of cement and to assess the relevance to clinical use and failure modes in vivo of these different means of testing.