FIG. 4.

Histologic analysis of calvarial defect healing. At 8 weeks, postmortem histologic analysis was performed by routine H & E and Masson's Trichrome staining. (A, B) Control-treated animals showed a sharp demarcation between the native parietal bone and fibrous tissue (black arrowhead) with scattered multinucleated giant cells (red arrowheads) and residual scaffold material (black asterisks). Scarce new bone formation was observed. (C, D) With 0.5 mM SAG, foci of new bone formation was observed, particularly at the defect edge. (E, F) With 1.0 mM SAG, significant new lamellar bone was observed, which was predominantly in continuity with the pre-existing parietal bone edge. Significant vascularity of the defect site was also noted in and around the bone interstices (white arrowheads). Black arrowheads indicate the margin of the native parietal bone. A single representative sample per treatment group is shown. Scale bar = 50 μm. Color images available online at www.liebertpub.com/tea