Comparison of direct and indirect non-thermal atmospheric plasma effect on human periodontal ligament stem cells

The purpose of this study was to find out the osteogenic potential of human periodontal ligament cells when treated with nitrogen gas using a specially designed plasma needle (non-porous type). Extracted third molars were used for cell culture and the cells were identified for their stem cell characteristics and phenotype. Further, the hPDL-MSCs (Human Periodontal derived Mesenchymal Stem Cells) were tested by direct and indirect plasma treatment for their viability, intracellular ROS (Reactive Oxygen Species) activity, differentiation and genotyping was done using q-PCR (Polymerase Chain Reaction). The results indicated that indirect treatment was beneficial for the viability and osteogenic differentiation of cells, while direct treatment due to its strong effect was detrimental to the periodontal cells. In comparison to highly elevated levels of H₂O₂, the ROS levels after direct and indirect plasma treatment were found to be quite low. The increase in gene expression markers was more with indirect treatment than with direct treatment. The difference in results of direct and indirect plasma treatment, may provide new insights for utilizing indirect plasma treatment methods for periodontal defect therapies, regeneration and tissue engineering for future periodontal treatment.