In Vitro and In Vivo Evaluation of Commercially Available Fibrin Gel as a Carrier of Alendronate for Bone Tissue Engineering

Figure 9

Goldner’s Masson trichrome-stained histological images of regenerated bone in the central area of calvarial defects at 2, 4, and 8 weeks after implantation. At 2 weeks, large amounts of fibroblastic connective tissue were observed in the fibrin gel and fibrin/ALN gel-implanted groups. Specifically, a small island-like amount of immature bone (black arrow) was observed in the fibrin/ALN gel-implanted group. Furthermore, mature bone islands (white arrow) were observed at 4 weeks and the newly formed bones were more abundant at 8 weeks in the fibrin/ALN-implanted group than in the fibrin gel-implanted group. Scale bar: 250 μm.