The production of nanofibers bearing proanthocyanidins and their effects on the odontoblastic differentiation potential of dental pulp stem cells

In this thesis study, bare poly-lactic acid nanofibers (PLA-Nf), 75 µg/mL proanthocyanidin-incorporated PLA_PA-Nf, and PLA-IC-Nf mats to enable the sustained release of proanthocyanidins through a β-CD-inclusion complex were fabricated through the electrospinning technique. The effects of nanofibers on viability and the odontogenic differentiation capability of DPSCs were investigated. The morphology, composition, hydrophilicity of the nanofibers was characterized by SEM, ATR-FTIR spectroscopy, and contact angle measurements, respectively. The release of PA from the fibers was monitored for 30 days at predetermined intervals. The inclusion complex enabled the electrospun PLA-IC-Nfs to demonstrate a more sustained release profile of PA compared to the PLA_PA-Nfs. The antioxidant capacity was evaluated using the 2,2-diphenyl-1-picrylhydrazyl assay, and the antibacterial effects against Staphylococcus aureus and Escherichia coli were investigated counting the colony-forming units. To assess odontogenic differentiation; calcium deposition, alkaline phosphatase activity, Alizarin red staining was measured at 14 and 18 days, while OCN, RUNX-2, DSPP, and DMP-1 gene expressions were evaluated at day 18. As a result, the successfully developed PLA-IC-Nf exhibited effective antibacterial activity against S. aureus and E. coli, antioxidant activity, and increased hydrophilicity compared to nanofibers without the inclusion complex. Although it showed initial cytotoxicity, which gradually decreased over time to levels comparable with DPSCs alone, allowing the cell culture to reestablish itself due to more controlled release. PLA-IC-Nf samples promoted odontogenic differentiation of DPSCs by upregulating the DSPP, DMP-1 and ALP activity.