In Vitro Comparison of Three-Dimensional Cultured Periodontal Ligament Stem Cells Derived from Permanent and Supernumerary Teeth

The characteristics of 3-dimensional (3D) cultured periodontal ligament stem cells derived from permanent teeth (pPDLSCs) and supernumerary teeth (sPDLSCs) were compared and evaluated in this study. pPDLSCs and sPDLSCs were cultured in an ultra-low attachment 6-well plate, and the changes in morphology and size were observed under an optical microscope for 14 days. Cell counting kit-8 was used to quantitatively evaluate cell viability, and a live/dead assay was performed for the qualitative assessment. The degrees of osteogenic, chondrogenic, and adipogenic differentiation of pPDLSCs and sPDLSCs were also assessed. The pPDLSCs and sPDLSCs were initially spherical, and sPDLSCs were smaller than pPDLSCs. The viability of pPDLSCs decreased by 47.9% (day 3) and 10.4% (day 7), whereas that of sPDLSCs decreased by 34.3% (day 3) and 2.5% (day 7) compared to the percentage on Day 1. No significant difference in osteogenic differentiation was found (p = 0.94); however, significant differences in adipocyte and cartilage differentiation were observed (p = 0.003 and p = 0.013, respectively). Within the limitations of this study, sPDLSCs and pPDLSCs exhibited multilineage differentiation capacities, including osteogenic, chondrogenic, and adipogenic differentiation, in 3D culture. Overall, pPDLSCs should be further investigated as a source of stem cells for tissue engineering and regenerative medicine.