Experimental and numerical analysis of the mechanical behavior of bone cement reinforced with alumina particles

The failure of polymethyl methacrylate (PMMA) orthopedic cement is considered the most important problem in total hip arthroplasty and eventual prosthesis loosening. Fiber or particulate reinforcement has been used to improve the mechanical properties of bone cement. However, reinforced cements have also been limited by adhesion between the PMMA and implant. This study investigated the effect of bioceramic particle reinforcement (alumina; Al 2 O 3 ) with different volumes (0, 5, 10, 15 and 20 vol%) on both the mechanical behavior of bone cements and implant–cement interface resistance. Mechanical fixation at the implant–cement interface was evaluated in vitro under shear mode loading conditions. Based on the mechanical tests of the implant–cement interface, a finite element model of the interface sample was developed to analyze the interfacial behavior of the implant–cement adhesion. The results show that the highest elastic modulus, tensile strength, compressive strength, and Vickers hardness (5.01 GPa, 41.33 MPa, 100.26 MPa and 10.36, respectively) were obtained using the PMMA sample with 20 vol% alumina particles, which represent increases of 82.8%, 78.68%, 42.37% and 282%, respectively, compared with those of pure PMMA. Against all expectations, beyond 10 vol% alumina, the interface strength dropped. The results also show that there is a good correlation between the numerical and experimental analysis methods.