Comparison between allogenic and xenogenic bone blocks on the osteogenic potential of cultured human periodontal ligament stem cells: Confocal laser and scanning electron microscopy study

Abstract

Aim: The aim of this study was to compare between equine and human bone blocks in the osteogenic differentiation of cultured human periodontal ligament stem cells (hPDLSCs) at 14 and 21 days of culture, using confocal laser microscopy and scanning electron microscopy. Materials and Methods: In vitro cultures of commercially obtained hPDLSCs were seeded onto equine and human bone blocks. At 14 days and 21 days of culture, confocal laser microscope images were obtained to assess cellular differentiation and adhesion, and scanning electron microscope images were obtained to validate the osteogenic differentiation by showing the morphological characteristics of the new bone cells. Results: Both equine and human bone blocks showed positive staining for newly formed bone cells through the confocal laser microscope analysis, however, a higher signal intensity was expressed at 21 days of culture. These findings indicate the biocompatibility of hPDLSC with both types of bone blocks, cellular differentiation, and adhesion. Scanning electron microscopy images validated the osteogenic differentiation by showing the common characteristics of bone cells as flattened, polygonal morphology with multiple extending cytoplasmic processes. Conclusion: Both equine and human bone blocks were able to confirm the osteogenic capability of seeded human PDLSC. There was no significant difference between equine and human bone blocks on the human PDLSC differentiation. Superior osteogenic differentiation of cultured hPDLSCs was evident at 21 days in comparison to 14 days.