Effects of Alendronate Sodium Content on the Interface Strengths of Composite Acrylic Bone Cement

Abstract

Objective. Aim to study how the content of alendronate affected shear strengths at bone-bone cement-metal interfaces.Methods. All samples were divided into 6 groups, G0–G5. On the 1st and 60th day after surgery, bone-bone cement interface shear strengths and bone densities were examined. Interface strengths of metal-bone cement specimens were studied before immersion and 4 weeks after immersion.Results. On the 60th day, bone-bone cement interface shear strengths and bone densities showed significant differences (P<0.05), and compared with G0, G2–G5values increased significantly (P<0.05), and the peak value was met in G3. Compared with the 1st day, on the 60th postoperative day both factors decreased significantly in G0and G1(P<0.05). Four weeks after immersion, with the increasing dose of alendronate, the shear strengths decreased gradually and in G5decreased significantly (P<0.05). Compared with before immersion, the metal-bone cement interface strengths decreased significantly 4 weeks after immersion (P<0.05).Conclusions. 50–500 mg alendronate in 50 g cement powders could prevent the decrease of shear strengths at bone-bone cement interfaces and had no effect on metal-bone cement interface strengths. While the addition dose was 100 mg, bone cement showed the best strengths.