Quantitative histomorphometry for histologic analysis of cranial defect reconstruction by collagen constructs 4 weeks post-surgery. (A) Percentage of reconstructed normal thickness and area of parietal bone in the three different groups. (B) Average number of vessels present in 0.12 mm of implant. Values, calculated on three slices of each of the 10 specimens for group, are expressed as mean ± standard deviation. *P ≤0.05, **P ≤0.01, ***P ≤0.001 versus collagen group; °P ≤0.05 versus collagen+DPSC group. AFSC, amniotic fluid stem cell; DPSC, dental pulp stem cell.