Human Dental Pulp Facilitates Bone Regeneration in a Rat Bone Defect Model

The objective of this work was to investigate the osteogenetic ability of the human dental pulp stem cells (hDPSCs) derived from human third molars. We induced alkaline phosphatase (ALP) activity and bone morphogenetic protein 2 (BMP-2) mRNA expression, the markers for bone formation, in hDPSCs by using osteoinductive factors. The implantation of hDPSCs with collagen sponge promoted osteogenesis and fracture healing in the femur of an immunocompromised rat, which was a bone defect model for pseudoarthrosis. Histological analyses revealed that after implantation of the hDPSCs, the size and number of osteoblasts and the rates of osteoid production and mineralization increased to an appreciable extent, whereas the rate of bone resorption decreased. We believe that hDPSC implantation is a simple and safe procedure that can be beneficial in bone regeneration therapy in clinical practice.