Handling Property Improvement of Nano Calcium Hydroxide from Indonesian Limestone with Different Solvent Vehicles

As intracanal endodontic medicament, calcium hydroxide [Ca(OH)2] paste needs to have good handling to reach the root canal system’s complexity and penetrate the dentinal tubule. This study aimed to evaluate the handling of synthesized nano Ca(OH)2 from natural limestone (CaCO3) of Palimanan, Indonesia, formulated with different solvents; distilled water, propylene glycol (PG), and polyethylene glycol (PEG). The handling property of the nano Ca(OH)2 prototype was evaluated compared to the conventional micro-sized Ca(OH)2 particle paste. Both Ca(OH)2 powder were mixed with three different solvents: water, PG, and PEG. Flowability was evaluated by measuring the spread area following ISO1566 for zinc phosphate cement. Injectability test was done by measuring paste quantity extruded through a syringe after applying 300N forced at a cross-head speed of 0.25mm/sec in the 30s in a Universal Testing Machine. Data were analyzed by ANOVA (P<0.05) and T-test as a post hoc multiple comparison tests. The handling of the nanosize Ca(OH)2 prototype was significantly higher than the conventional Ca(OH)2. PG with nanosize Ca(OH)2 prototype demonstrated the best performance in flowability, while the water solvent had the best injectability compared to other solvents. The injectability and flowability of Ca(OH)2 paste is related to its particle size and solvent, which were improved by nanosized Ca(OH)2.