Effect of various solutions on the removal of orange-brown precipitate formed by interaction of sodium hypochlorite and chlorhexidine with or without ultrasonic activationZ

Objectives: This study aimed to compare the effect of different solutions on the removal of orange-brown precipitate with or without ultrasonic activation. Materials and Methods: One hundred and twenty extracted maxillary anterior teeth were instrumented. In experimental groups (n = 10), canals were flushed with 17% EDTA, 10% citric acid, 1% phytic acid, 96% alcohol and distilled water either using syringe irrigation or ultrasonic activation, after creating orange-brown precipitate. Teeth were sectioned longitudinally and subjected to stereomicroscopic analysis. The amount of precipitate was scored and the data were analyzed (P = 0.05). Results: There were no differences detected among the tested solutions (P > 0.05). There was a significant difference between ultrasonically activated irrigation and syringe irrigation for EDTA and distilled water in coronal, middle portions (P < 0.05). Conclusions: Ultrasonic activation significantly improved the precipitate removal capacity of EDTA and DW. Tested solutions were similarly effective regarding the removal of the precipitate.