Early Pulp Healing after Direct Pulp Capping with Concentrated Platelet-Rich Fibrin: A Preliminary Study

Direct pulp capping preserves pulp vitality after pulp exposure. Mineral trioxide aggregate (MTA) is widely used but relies mainly on host-mediated repair. Concentrated platelet-rich fibrin (C-PRF), an autologous plasma-derived biomaterial, may actively modulate the local healing microenvironment through sustained delivery of bioactive factors, but its biological performance in direct pulp capping has not been fully characterized.

Human dental pulp cells (hDPCs) were treated with PBS, MTA, or C-PRF to assess viability, proliferation, migration, and mineralization via live/dead staining, CCK-8, scratch and transwell assays, ALP and Alizarin Red S staining, as well as qPCR for genes encoding ALP, RUNX2, and COL1A1. Furthermore, an in vivo rabbit direct pulp capping model was utilized and treated with MTA or C-PRF. Pulp regenerative potential was evaluated using H&E, Masson's trichrome, and CD31 immunohistochemistry, with quantitative analysis of vascularization.

C-PRF demonstrated good biocompatibility and enhanced hDPCs migration, proliferation, and mineralization compared with MTA. In vivo, the C-PRF group exhibited increased CD31-positive staining, suggesting enhanced early vascular responses.

Within the limitations of this study, C-PRF enhanced cellular responses, including migration and mineralization, and showed potential to promote early vascularization. These findings suggest that C-PRF may serve as a biologically active adjunct for direct pulp capping.