Figure 5: Shows representative histological pictures of the histochemical TRAP detection of both analyzed collagen-based materials at day 15 after implantation (A: BEGO Collagen Fleece (CFM), B: BEGO Collagen Membrane (CM)). In both cases the multinucleated giant cells (red arrow heads) as well as the mononuclear cells at the surface of the materials (black arrow heads) and within materials bodies (arrows) showed almost no signs of TRAP expression (TRAP-stainings, 400x magnifications, scale bars = 10 μm).