Chemical interactions among some antimicrobial solutions and chelating agents used in endodontics for irrigation of infected root canals

Abstract

The root canal irrigants are of utmost importance in the soft tissue dissolving, the removal of microorganisms, hard-Tissue debris, and smear layer. This study sets forth to investigate the stability and synergic interactions of different systems with various combinations among antimicrobial substances and chelating agents, frequently used in endodontics for the irrigation of the infected root canals through electrochemical evaluation, physicochemical and spectrophotometric analysis. The pharmaceutical products indicated as the antiseptic solutions (sodium hypochlorite-NaOCl, chlorhexidine-CHX) and chelating agents (EDTA, citric acid-CA) have large pH variations on the entire pH domain. The physicochemical parameters' (pH, conductivity) assessment at the CHX and CA solutions shown good stability in time and also electrochemical behaviour (OCP, CV). There is a dissociation of ions in aqueous medium and a competition of the chemical balances among the structures, as an intense electrochemical activity between the functional groups through the intensification of the anodic current currents, and a shift of the potential registered. This allows the formulation that chemical interactions are not always possible among diverse types of antimicrobial solutions and chelating agents for endodontic use.