Figure 3. Mineralized scaffolds support enhanced bone tissue ingrowth, and biomineral presence significantly enhances osteoid matrix deposition. (A,B) Hematoxylin and eosin (H&E) staining of sections of a critical-sized defect without an implanted scaffold (A) and a defect after implantation of a mineralized, VEGF-releasing PLG scaffold (B). Bridging of the defect area with tissue was evident for all three experimental conditions (data not shown). (C-E) Higher-magnification H&E staining of implanted PLG (C), mineralized PLG (D), and VEGF-releasing, mineralized PLG (E) scaffolds 14 wks postimplantation. (F-H) Goldner’s trichrome staining of implanted PLG (F), mineralized PLG (G), and VEGF-releasing, mineralized PLG (H) scaffolds 14 wks post-implantation (red = osteoid matrix). (I) Quantification of osteoid matrix fractional area within the scaffold area for each condition. *P < 0.05 relative to the PLG condition (n = 5 for PLG and MIN; n = 6 for MIN + VEGF). Data in plot represent mean ± standard deviation. Scale bar = 1 mm (in A-B) or 100 µm (in C-H).