Odontoblast differentiation of DPSCs/progenitors by BBX overexpression. (A) BBX variant 1 and 2 were overexpressed using electroporation, and their expression was confirmed by RT-PCR. (B) ALP activity (on day 10) was increased by BBX overexpression (upper panel). Mineralization was assessed by alizarin red S staining and BBX overexpression induced an increase in mineralization (on day 25) compared to the controls (middle panel). The alizarin red S stain was extracted and the OD was measured (lower graph). (C) The expression of several odontoblast differentiation markers was analyzed by RT-PCR, and they were increased in the BBX-overexpressing cells than in the empty vector-expressing cells on day 14. All experiments were performed in triplicate.