Effect of Different Dental Pulp Capping Materials on the Proliferation and Odontogenic Differentiation of Dental Origin Derived Mesenchymal Stem Cells

Objectives: Examination of the effect of dental capping materials (TheraCal LC, Nano hydroxyapatite, Biodentine and Mineral trioxide aggregate) on odontogenic differentiation and proliferation of human dental pulp stem cells.
Methods: Clinical work was done through seven phases: I, isolation and cell culture of dental pulp stem cells from human extracted teeth. II, characterization of isolated human dental pulp stem cells (hDPSCs) by flow cytometric analysis. III, The capping materials were placed at the bottom of well plate. hDPSCs were seeded on the tested materials at 3000 cells/well. IV, cell viability assessment by using MTT cell proliferation assay. V, odontogenic differentiation of hDPSCs. VI, Assessment of the effect of the capping materials on odontogenic differentiation of hDPSCs by Real time PCR for detection of gene expression of dentin sialophosphoprotein (DSPP) and collagen type 1, and measurement of alkaline phosphatase activity. VII, visualization of calcium depositions by von Kossa staining. Data analysis was done using the Kruskal-Wallis, and Dunn-Bonferroni tests.
Results: Biodentine group showed significantly higher cell viability (41.33%), Nano hydroxyapatite (29.50%), MTA (29.00%) and TheraCal LC (20.83%) groups. Regarding gene expression of both DSPP and collagen type I, there was statistically significant difference in their percentage between the tested materials (X² (4) =39.091, P= 0.000), the mean rank of hDPSCs DSPP and collagen type I gene expression was significantly higher in Biodentine group. For alkaline phosphatase activity, Biodentine (43.58), NHA (37.33), MTA (32.25), and TheraCal LC group (25.83). Von Kossa staining measurements shows that Biodentine group has the most calcified mineralization effect, while the TheraCal LC group has the least.
Conclusions: Biodentine dental capping material showed high odontogenic ability with low toxicity compared with NHA, MTA and TheraCal LC. The present results provide support for Biodentine use in pulp capping materials to increase the efficiency of the therapy.