Biodegradable borosilicate bioactive glass scaffolds with a trabecular microstructure for bone repair

Three-dimensional porous scaffolds of a borosilicate bioactive glass (designated 13-93B1), with the composition 6Na(2)O-8K(2)O-8MgO-22CaO-18B(2)O(3)-36SiO(2)-2P(2)O(5) (mol%), were prepared using a foam replication technique and evaluated in vitro and in vivo. Immersion of the scaffolds for 30 days in a simulated body fluid in vitro resulted in partial conversion of the glass to a porous hydroxyapatite composed of fine needle-like particles. The capacity of the scaffolds to support bone formation in vivo was evaluated in non-critical sized defects created in the femoral head of rabbits. Eight weeks post-implantation, the scaffolds were partially converted to hydroxyapatite, and they were well integrated with newly-formed bone. When loaded with platelet-rich plasma (PRP), the scaffolds supported bone regeneration in segmental defects in the diaphysis of rabbit radii. The results indicate that these 13-93B1 scaffolds, loaded with PRP or without PRP, are beneficial for bone repair due to their biocompatibility, conversion to hydroxyapatite, and in vivo bone regenerative properties. (C) 2013 Elsevier B.V. All rights reserved.