Apatite formation on PDMS-modified CaO-SiO2-TiO2 hybrids prepared by sol-gel process

Dense and homogeneous monolithics of polydimethylsiloxane (PDMS)-modified C aO-SiO2-TiO2 hybrids were successfully synthesized by sol-gel process. They were assumed to be composed of a silica and titania network incorporated w ith PDMS and the calcium ion ionically bonded to the network. Among them, t he hybrids containing relatively larger amounts of the calcium in their sur faces formed an apatite on their surfaces within only 1 or 0.5 day in a sim ulated body fluid with ion concentrations nearly equal to those of human fl ood plasma. This indicates that they are highly bioactive. Organic-inorgani c hybrids synthesized by a sol-gel process usually exhibit high ductility, low elastic modulus and high mechanical strength. The present hybrids are, therefore, expected to be useful as a new kind of bone-repairing material, because of their high bioactivity and unique mechanical properties. (C) 199 9 Elsevier Science Ltd. All rights reserved.