Fig. 2.

Ectopic bone formation assay after implanting whole blood coagulum device (WBCD) OSTEOGROW (white circle) subcutaneously in the axillary region (circles) of a rat (a). Two weeks later μCT analysis in axial (b) and longitudinal (c) planes showed a newly formed mineralized ossicle (white arrows). Histological sections stained by von Kossa (d) and toluidine blue (e) demonstrate mineralized bone with a bone marrow and absence of inflammation and fibrosis at the external surface of the ossicle (arrow in d), which is usually covered by a thick layer of fibrotic tissue in the form of a fibrous capsule when commercially available Osigraft (3.5 mg BMP7) or Infuse (1.5 mg/ml BMP2) are used on a bovine collagen carrier at a subcutaneous site in rats (results not shown)