DEVELOPMENT AND CHARACTERIZATION OF SODIUM HYPOCHLORITE GEL FORMULATION FOR ENDODONTIC USE
Endodontics, Root Canal Irrigants, Surface-Active Agents.
This research focused on the development and characterization of a gel formulation for NaOCl, which allows greater control during the root canals irrigation without losing the characteristics that make it such na efficient cleaning and decontamination agent. It was used a concentrated solution of NaOCl, which was titrated to determine the active chlorine content, and a surfactant, sodium lauryl ether sulfate, for which the critical micellar concentration in distilled water was calculated. From these reagents were carried out dilutions and manipulated seven formulations of 2.5% NaOCl with different surfactant concentrations, which were submitted to the following analysis: pH, surface tension, Fourier transform infrared spectroscopy (FTIR), wettability on human dentin, rheology and antibacterial potential against Enterococcus faecalis. The pH values showed that the addition of the surfactant did not alter this parameter, keeping the alkaline medium desirable for NaOCl action. The surfactant addition reduced surface tension by more than 50% relative to the NaOCl aqueous solution. The FTIR showed that the reagents only solubilize and interact, not implying the occurrence of chemical reaction between them. The wettability on human dentin was lower than that measured for the NaOCl solution. The viscosity study revealed micellar solution behavior for the formulations with lower concentrations of surfactant, and gel behavior for the more concentrated ones. All formulations showed viscosity and appearance that allow clinical use satisfactorily. The microbiological disk-diffusion test on agar showed a satisfactory action similar to the 2.5% aqueous NaOCl solution.