Effect of antibiotic loading on the shear strength at the stem-cement interface (Shear strength of antibiotic loaded cement)

The purpose of this study was to investigate the effects of addition of antibiotics into cement powder on the shear properties of the cement-metal interface. The approach involved adding 800 mg of teicoplanin to 40 g bone cement powder in the t-800 group, 1,600 mg teicoplanin in the t-1,600 group, and no antibiotic in the control group. Industrially prepared bone cement containing 500 mg of gentamicin was used as group g-500. Each group consisted of ten samples. Cement-metal interfaces were produced using metal discs with porous surfaces (1 mu m) and templates at the third minute. Shear stability of specimens was measured in a material testing machine. The ANOVA test was used for comparison between the mean shear results of each group. Results showed that mean shear stress to failure values were 12.28 +/- 3.35 MPa for the control group, 11.72 +/- 3.09 MPa for the t-800 group, 13.25 +/- 2.36 MPa for the t-1,600 group and 13.09 +/- 2.58 MPa for the g-500 group. No statistically significant differences were found between results of the groups. Results of the study have proven that addition of 1,600 mg of teicoplanin or 500 mg gentamycin in 40 g of bone cement does not decrease the shear strength at the cement-metal interface significantly on the day of application.