Exploring vitamin K2 and B12 as bioactive micronutrients for dentin conditioning in regenerative endodontics...

This study assessed the potential of vitamins K2 and B12 as dentin surface conditioners to modulate the regenerative behavior of human periodontal ligament stem cells (hPDLSCs). hPDLSCs were isolated and characterized by flow cytometry, which confirmed the mesenchymal stem cell phenotype. Cell viability assays showed no cytotoxicity at the tested concentrations; therefore, 16 µg/mL was selected for further analysis. Both vitamins significantly enhanced cell migration, attachment to dentin disks, and mineralization potential, as demonstrated by Alizarin Red staining and alkaline phosphatase activity after 14 days of osteogenic induction. Gene expression analysis revealed that vitamin B12 primarily upregulated RUNX2, whereas vitamin K2 increased the expression of osteoprotegerin, osteocalcin, dentin sialophosphoprotein, and cementum protein 1. Furthermore, both vitamins reduced the expression of nuclear factor kappa-B and interleukin-6 and increased glutathione levels, with vitamin B12 exhibiting stronger anti-inflammatory and antioxidant effects. Despite these variations, no significant differences were observed between the two vitamins in terms of cell proliferation, mineralized nodule formation, or alkaline phosphatase activity, suggesting a comparable overall regenerative potential. These findings indicate that vitamins K2 and B12 are biocompatible and promote favorable hPDLSC responses through distinct molecular pathways. They may serve as practical, chairside-applied micronutrient conditioners in regenerative endodontic procedures, potentially improving the treatment outcomes.