Ability of smear layer removal using different chelated irrigations

Objectives: The purpose of this study was to compare removing ability of smear layer on surface of root canal with different chelated irrigations and scanning electron microscopical observation. Methods: 33 human single root teeth were used which had been divided into 11 groups----pH=6.5 15% EDTA; PH=7 5% EGTA,10% EGTA, 15% EGTA;pH=6 EGTA; PH=8 EGTA;5% citric acid, 10% citric acid,15% citric acid; chelated irrigation+2% Chloramine; 3% H₂O₂+2% Chloramine. All the teeth were decoronated ,extirpated pulp, instrumented and irrigated. Then splited teeth in longitude and observed by scanning electron microscopy. Results: All the irrigations could remove the smear layer from the upper, middle, apical third of root canal and were observed opened dentinal tubules except 5% EGTA,5% citric acid. However the most effiective irrigation was PH=6 10% EGTA+2% Chloramine. Conclusion: Chloramine could enhance the ability of smear layer removal with chelated irrigation.