Comparative analysis of the antimicrobial potential of different intra-canal medication to microorganisms present in the failure of the endodontic therapy: In vitro study

Microorganisms that infect the root canals system are the main etiologic factor of the periapical pathologies. Some microorganisms are resistant to the antimicrobial treatment and may survive in the root canal after the chemical mechanical preparation and intra-canal medication, characterizing a persistent infection. In cases of failure of the endodontic treatment, a new approach may be done using additional measures that involve this infectious process control through the elimination or maximum reduction of microorganisms. Therefore, this article aims to evaluate the antimicrobial potential of different formulations of intra-canal medication compared to strains of Enterococcus faecalis, Pseudomonas aeruginosa and Staphylococcus aureus in Petri plates. It was used diffusion test in agar where each Petri plate with the inoculated bacteria presented 5 wells that were filled with each medication. The diameters of the bacterial inhibition zones were measured and registered to each tested medication at the period of 24 hours, 48 hours, 1 week and 2 weeks. All the medications promoted inhibition halos; however, a higher elimination of micro-organisms can be significantly achieved through the association of different substances in the formulation of an intra-canal medication, with emphasis to HPG and Ca(OH)2 + CHX.