Novel combination of nanostructured calcium hydroxide and natural materials: Formulation and characterization

Background. Calcium hydroxide is used as a reparative dentin inducer. The combination of cocoa pod husk and calcium hydroxide has also been studied as a reparative dentin inducer, whereas anchovy was identified as a good calcium source. Objectives. The aim of the study was to investigate the optimal ratio of a nano-combination of calcium hydroxide, cocoa pod husk extract and anchovy powder as a reparative dentin inducer by analyzing their material, antioxidant and cytotoxic properties. Material and methods. The ratios of the 3 elements were established and their performance was compared in terms of viscosity, setting time, pH, and solubility rate. The optimal ratio was then examined for its antioxidant capacity using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. Additionally, its cytotoxicity against human dental pulp stem cells (hDPSCs) was evaluated through the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Results. A ratio of 1:1:1 of calcium hydroxide, cocoa pod husk extract and anchovy powder was identified as the optimal ratio. It exhibited the greatest flowability, the shortest final setting time, had a pH range of 8.5–10.5, and the second highest solubility rate in comparison with other ratios. Moreover, it demonstrated active radical scavenging activity and stimulated the proliferation of hDPSCs. Conclusions. Based on the material, antioxidant and cytotoxic properties, a ratio of 1:1:1 of nano-calcium hydroxide, cocoa pod husk extract and anchovy powder was determined to be optimal for use as a reparative dentin inducer.