Pages 435-436
PMMA-based bone cement is commercially used for anchoring implants, such as artificial hip joints, with bone. However, it has a major problem on prosthesis loosening due to coverage by fibrous tissues after long-term implantation. A novel design of bone cement exhibiting bone-bonding ability i. e. bioactivity is desired. In order for artificial materials to bond directly to bone, formation of an apatite layer on the artificial surface is prerequisite. This apatite formation is triggered both by release of calcium ions (Ca^<2+>) from the materials, and by catalytic effect on induction of apatite nucleation by silanol (Si-OH) groups on their surfaces. The present authors have recently developed bioactive PMMA-based bone cement through modification with γ-methacryloxypropyltrimethoxysilane (MPS) and various kinds of calcium salts. In this study, effects of chemical modification on its mechanical properties were examined in a simulated body fluid (SBF). Four point bending strength of modified cements after soaking in SBF increased in the order : Ca(OH)_2 < Ca(CH_3COO)_2 < Commercial bone cement < No modification (Reference).
