Isolation and Characterization of Human Dental Pulp Stem Cells from Cryopreserved Pulp Tissues Obtained from Teeth with Irreversible Pulpitis

Introduction: Human dental pulp stem cells (DPSCs). are becoming an attractive target for therapeutic purposes because of their neural crest origin and propensity. Although DPSCs can be successfully cryopreserved, there are hardly any reports on cryopreservation of dental pulp tissues obtained from teeth diagnosed with symptomatic irreversible pulpitis during endodontic treatment and isolation and characterization of DPSCs from such cryopreserved pulp. The aim of this study was to cryopreserve the said pulp tissues to propagate and characterize isolated DPSCs. Methods: A medium consisting of 90% fetal bovine serum and 10% dimethyl sulfoxide was used for cryopreservation of pulp tissues. DPSCs were isolated from fresh and cryopreserved pulp tissues using an enzymatic method. Cell viability and proliferation were determined using the MIT [3,4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. DPSC migration and interaction were analyzed with the wound healing assay. Mesenchymal characteristics of DPSCs were verified by flow cytometric analysis of cell surface CD markers. The osteogenic and adipogenic potential of DPSCs was shown by von Kossa and oil red 0 staining methods, respectively, and the polymerase chain reaction method. Result: We found no significant difference in CD marker expression and osteogenic and adipogenic differentiation potential of DPSCs obtained from fresh and cryopreserved dental pulp tissue. Conclusions: Our study shows that dental pulp can be successfully cryopreserved without losing normal characteristics and differentiation potential of their DPSCs, thus making them suitable for dental banking and future therapeutic purposes.