In vitro analysis of dentinal permeability promoted by different chemical solutions used in root canal final irrigation

Abstract

The present comparative stu- dy aims to evaluate the actions of three root canal irrigating so- lutions on dentinal permeability. The solutions tested were 17% EDTA (ethilene-diamino tetracetic acid), 50% citric acid and anionic detergent. Thirty extracted per- manent maxillary canines were used, divided into three groups of ten elements each. The specimens were instrumented with the aid of 1% sodium hypochlorite; after finishing the chemical-surgical preparation, group 1 was irriga- ted with 50% citric acid, group 2 with 17% EDTA and, group 3, with anionic detergent. The ca- nals were dried, received coronal sealing and made impermeable with two coatings of ethila cyano- acrylate (Super Bonder), staying open only the apical foramen; they were kept for 72 hours in methyle- ne blue and washed for 1 hour in water, then submitted to cleavage. Quantitative analysis was carried out, with microcomputer and ima- ge system aid, assessing the pene- tration of the stain into the speci- mens. Kruskal Walllis statistical analysis showed a higher infil- tration on the stain for the group of teeth irrigated with 50% citric acid (p < 0,01), when compared to the other groups that were equal to each other. It can be concluded that 50% citric acid has the best level of methylene blue stain infil- tration in the specimens tested. Key words: EDTA, citric acid, irri- gation, permeability, infiltration.