Figure 4 Osteogenic/dentinogenic differentiation induction analysis. (A) Mineralized nodules were detected after 14 days of induction following alizarin red (AR) staining. “+”, inductive medium; “−”, control medium. Scale bar, 100 μm. (B) The bar chart represents the percentage of area positively stained for AR (mean±standard deviation) analyzed from 5 samples, * P<0.05. (C, D) Several osteogenic/dentinogenic lineage-specific genes were examined by quantitative real-time polymerase chain reaction after 1-week and 2-week induction, * P<0.05. DPSCs – dental pulp stem cells; iDPSCs – inflammatory dental pulp stem cells. (Figure were created using Adobe Photoshop CS3, Adobe Systems Software Ireland, Ltd.).