  Macroporous scaffolds made of a SiO2-CaO-P2O5 mesoporous bioactive glass
(MBG) and epolycaprolactone (PCL) have been prepared by robocasting. These
scaffolds showed an excellent in vitro biocompatibility in contact with
osteoblast like cells (Saos 2) and osteoclasts derived from RAW 264.7
macrophages. In vivo studies were carried out by implantation into cavitary
defects drilled in osteoporotic sheep. The scaffolds evidenced excellent bone
regeneration properties, promoting new bone formation at both the peripheral
and the inner parts of the scaffolds, thick trabeculae, high vascularization
and high presence of osteoblasts and osteoclasts. In order to evaluate the
effects of the local release of an antiosteoporotic drug, 1% (%wt) of
zoledronic acid was incorporated to the scaffolds. The scaffolds loaded with
zoledronic acid induced apoptosis in Saos 2 cells, impeded osteoclast
differentiation in a time dependent manner and inhibited bone healing,
promoting an intense inflammatory response in osteoporotic sheep.
