The cleaning efficiency of the root canal after different instrumentation technique and irrigation protocol: A SEM analysis

Aim: The objective of this study was to evaluate the effectiveness of manual and ultrasonic instrumentation with varying irrigation protocols on removal of the smear layer from root canal walls. Methods: Forty extracted single rooted human teeth stored in 0.5% saline were used. Periodontal soft tissues were removed followed by crown separation at the CEJ. All the teeth were randomly divided into two groups. Manually Instrumented Group 1 was irrigated with 5.25% NaOCl and 17% EDTA alternately, same as Ultrasonically Instrumented Group 2. The controls for both groups were irrigated with saline solution. Results: Ultrasonic instrumentation and the combined use of two different solutions (5.25% NaOCl and 17% EDTA) yielded better results on smear removal. Conclusions: Irrigation with 17% EDTA followed by 5.25% NaOCl was successful in complete removal of smear layer on cervical and middle thirds of the root canals. Ultrasonic instrumentation was slightly more successful on the apical one third of the root canals.