Fig. 1

Schematic diagram of the experimental design. a Osteogenic differentiation of DPPSC cultures. Undifferentiated DPPSC were cultivated during 15 passages, from 6 different donors. The genetic stability was checked at passages 1, 5, 10 and 15 by sCGH. 2D osteogenic differentiation: DPPSC from 3 of the 6 donors at P10 were differentiated during 21 days with osteogenic media in plastic culture plates. 3D osteogenic differentiation: DPPSC from 2 of the same donors (at passages 1, 5 and 10) used also in 2D differentiation were differentiated on biomaterials (CCC and Ti disks) during 21 and 15 days. DPPSC after 15 days of osteogenic 2D differentiation (B.DPPSC) were also seeded on titanium disks and maintained during 15 days more in osteogenic medium (TI B.DPPSC). sCGH was performed in all DPPSC differentiations. b SAOS-2 at P10 were used as a control cell line in all experiments. Genetic instability of SAOS-2 was evaluated before osteogenic induction experiments. DPPSC, Dental pulp pluripotent stem cells; SAOS-2, human osteosarcoma cell line; B.DPPSC, Bone-like DPPSC, differentiated 15 days in 2D conditions; TI DPPSC, DPPSC differentiated on titanium disks; TI B. DPPSC, Bone-like DPPSC differentiated on titanium disks; CCC, Collagen I-based Cell Carrier; TI disks, Ti6Al4V disks; sCGH, short-chromosome genetic hybridization