The effect of calcium hydroxide nanoparticles on the mineralization of dental pulp stem cells

Abstract

Abstract Introduction: Stimulating osteogenic/odontogenic differentiation of dental pulp stem cells and bio-mineralization is an essential aim of regenerative endodontics. Previous studies have shown better mechanical properties for calcium hydroxide nanoparticles (CHNPs) in comparison to conventional calcium hydroxide (CH). This in vitro study aimed to evaluate and compare the effect of CH and CHNPs on biomineralization of human mesenchymal stem cells (HMSCs). Methods: Synthesized CHNPs were characterized using scanning electron microscopy (SEM). The viability of HMSCs was measured by a 3-(4,5-dimethylthiazolyl-2-yl)-2,5-diphenyltetrazolium bromide assay after 7, 14 and 21 days after exposure of HMSCs to selected dose (0.25 µg/ml) of CH and CHNPs . Odontogenic potential of CH and CHNPs was investigated by alkaline phosphatase (ALP) activity and alizarin red staining over a 21-day period. The data were presented as mean ± SD and analyzed using One-Way ANOVA with Tukey post hoc. Results: Both CH and CHNPs exhibited cell viability over a 21-day period, which was higher in CHNPs than CH , however this superiority was not statistically significant (p>0.05). The ALP activity was increased in both groups compared to the control group (p<0.05) and CHNPs had superior effect on odontogenic activity than CH.(p<0.05) Conclusions: It can be concluded that CHNPs can be considered as appropriate bio-engineered material for osteogenic/odontogenic trans-differentiation in vitro