Figure 6: Evaluation of PRF as a scaffold in nude mice subcutaneous implants. This figure contains micrographs of paraffin sections through the center of the implant stained using Mallory’s connective tissue stain. (a) After 7 days of implantation, the PRF implant remained fairly intact and was only surrounded by collagen fibers in the periphery of the implant. (b) After 14 days of implantation, the size of the PRF scaffold (PRF) was reduced and mostly replaced with collagen fibers (Coll, here stained in blue). (c) and (d) illustrate histology of the 14-day implant at higher magnification. Note small collagen fibers (light blue) present within the pores of the implant (, (c)). (d) demonstrates new collagen fiber formation (Coll) replacing the PRF implant. (a) and (b) bar = 200 μm; (c) and (d) bar = 50 μm.