Evaluation of cleaning capacity and instrumentation time of manual, hybrid and rotary instrumentation techniques in primary molars

Pinheiro SL, Araujo G, Bincelli I, Cunha R, Bueno C. Evaluation of cleaning capacity and instrumentation time of manual, hybrid and rotary instrumentation techniques in primary molars. International Endodontic Journal, 45, 379–385, 2012. Aim To compare the cleaning effectiveness of manual, hybrid and rotary instrumentation techniques in primary molar teeth. Methodology Fifteen primary molars were selected. After endodontic access, the teeth were immersed in a medium containing Enterococcus faecalis and divided into three groups, according to the root canal instrumentation technique: group 1 – manual, group 2 – hybrid and group 3 – nickel–titanium (NiTi) rotary files. For microbiological evaluation, comparisons before and after instrumentation were performed using the paired Student’s t‐test. One‐way anova complemented with the Student’s t‐test was used to compare the percentage of microbial reduction. Instrumentation time was evaluated by Kruskal–Wallis and Student–Newman–Keuls tests. Images obtained under scanning electron microscopy were analysed by three blinded examiners, and kappa statistics was used to evaluate calibration among examiners. The most frequent results among examiners were analysed using Kruskal–Wallis and Student–Newman–Keuls tests. Results The hybrid technique required a significantly longer instrumentation time than the manual and rotary techniques (P