A regenerative strategy for vital pulp therapy: Platelet-rich fibrin augments stem cell viability and pluripotency in bioactive cement environments

Background Vital pulp therapy (VPT) aims to preserve pulp vitality and stimulate regeneration of the dentin–pulp complex. Dental pulp stem cells (DPSCs) are clonogenic mesenchymal stem cells with high self-renewal and multipotent differentiation capacity. Bioactive cements such as mineral trioxide aggregate (MTA) and calcium-enriched mixture (CEM) are widely used as pulp-capping agents due to their biocompatibility. Platelet-rich fibrin (PRF), an autologous fibrin matrix rich in cytokines and growth factors, has been used to support tissue healing and regeneration. Methods Human third-molar DPSCs were isolated and characterized, then cultured with MTA, CEM, and combinations of cement with PRF. Cell viability was assessed using the MTT assay, and expression of pluripotency markers (OCT4, SOX2, NANOG) was quantified by real-time PCR. Results MTT assays showed that CEM alone significantly reduced DPSC viability compared to control, whereas MTA and MTA + PRF did not differ from control. Notably, co-treatment with PRF attenuated CEM's adverse effect. NANOG was significantly upregulated in the MTA and MTA + PRF groups relative to control, and SOX2 was significantly elevated in the MTA + PRF group. OCT4 remained unchanged across all conditions. Conclusion The combination of MTA and PRF enhanced DPSC survival and upregulated pluripotency markers (NANOG, SOX2), supporting its potential application in regenerative VPT. In contrast, CEM alone had a detrimental effect on cell viability; however, this adverse effect was attenuated by PRF co-application. These findings suggest that MTA + PRF is a promising pulp-capping strategy for preserving DPSC function and promoting pulp regeneration.