Figures 6–8. Figure 6. Quantification of new bone formation suggested that nanometer-hydroxyapatite-augmented poly(propylene glycol-co-fumaric acid) materials supported new bone formation at a faster rate through 4 weeks than did the other treatments. The quantity of newly formed bone was approximately equivalent for all treatments at 7 and 12 weeks postoperative. Figure 7. The number of osteoclasts identified in the defect site peaked at 4 weeks postoperative and was highest in the untreated defects. Figure 8. Bone resorption at the defect perimeter peaked at 4 weeks postoperative for all treatments except demineralized freeze-dried human bone allograft, where resorption was approximately equivalent at 2 and 4 weeks. Resorption was highest in the untreated defects at all evaluation periods