Bioactivity and Mechanical Property of PMMA Bone Cement: Effect of Silanized Mesoporous Borosilicate Bioglass Microspheres

Poly(methyl methacrylate) (PMMA) bone cement is widely used in orthopaedic surgery as an injectable artificial bone repair material due to its advantages such as desirable mechanical properties, suitable curing time and low toxicity. However, its bioinert polymer may lead to aseptic loosening of the prostheses after long-term implantation. Here, silanized mesoporous borosilicate bioglass microspheres (MBGSSI) composite with PMMA bone cement was prepared to obtain ideal bone repair material with desirable bioactivity and mechanical properties. Mesoporous borosilicate bioglass microspheres (MBGS) were prepared by template method and modified by silane coupling agent gamma-methylacryloxy propyl trimethoxysilane (gamma-MPS) to obtain MBGSSI. The results indicated that MBGSSI possessed increased specific surface area and decreased total pore volume than MBGS did by the binding between gamma-MPS and MBGS occurred on the near surface of mesoporous microspheres. Compared with MBGS/PMMA, MBGSSI/PMMA composite bone cements demonstrated improved mechanical properties, which met the mechanical properties requirements of ISO 5833:2002 because gamma-MPS improved the combination between inorganic and organic phases of composite. In addition, the hydroxyapatite (HA) could widely form on the surface of both MBGS/PMMA and MBGSSI/PMMA composite bone cements after immersing in SBF for 42 d, demonstrating the excellent bioactivity. Hence, it is suggested that MBGSSI/PMMA can be a potential bone repair material.