Mean percent total area of bone. The area fraction (Aa) of regenerated bone within the defects was statistically significant compared to the various groups. The dashed line indicates no statistical difference (P ≥ .05) in the Aa between the 1% demineralized freeze-dried bone allograft (DFDBA), 3% to 6% DFDBA, and the control group, but the 2% DFDBA group showed statistically more vital bone compared to all other groups (P ≤ .05). The height of the bar graph indicates the mean; *, statistical significance.