Fig. 4

Detection of the alteration of osteogenesis-related indexes at the gene and protein levels. Pre/non-preconditioned PDLSCs were cultured in an osteogenic inductive medium without stimulations. A–I After 3, 7, 14 days of osteogenic induction, the RNA and protein were collected for RT-PCR and Western blot assay. (No matching letter (e.g.: a, b, c, d) above any two column charts represents a significant difference between these two groups (p < 0.05), while the appearance of any matching letters (e.g.: a, a) means that there is no significant difference among groups (p > 0.05). Data are expressed as mean ± SD)