Inconclusive results were reported about the cleaning and disinfection accomplished by the two irrigation methods .
There is insufficient evidence to cl aim general superiority of any one of these methods .
The aim of this study was to systematic ally review and critically analyse the published data on the treatment outcome ( primary outcome ) and on the  cleaning and disinfection of root canals  ( secondary outcomes ) achieved by negative pressure irrigation as compared to syringe irrigation .
In vitro comparisons of debris removal of the EndoActivator system, the F file, ultrasonic irrigation, and NaOCl irrigation alone after hand-rotary instrumentation in human mandibular molars.
INTRODUCTION The purpose of this in vitro study was to compare the debris removal efficacy of the EndoActivator system , the F file , ultrasonic irrigation , or 6 % NaOCl irrigation alone in human m and ibular molars after h and -rotary instrumentation . METHODS A custom brass cube ( K-Kube ) was used to create a sealed canal system , allowing each tooth to serve as its own control . Forty extracted m and ibular molars were r and omly divided into 4 equal experimental groups . Each tooth was mounted , sectioned at 1 , 3 , and 5 mm from the working length , and then reassembled into the K-Kube , and the mesial roots were similarly prepared by using h and -rotary instrumentation . For final debridement , group 1 used F file for 30 seconds , group 2 used EndoActivator system for 30 seconds , group 3 used ultrasonic irrigation for 30 seconds , and group 4 used irrigation with 6 % NaOCl within 1 mm of working length . All groups received a final irrigation with 6 % NaOCl in each canal . Specimens were evaluated at 1 , 3 , and 5 mm from the working length for cleanliness by capturing a digital image with a stereomicroscope . All specimens had the percent cleanliness for each canal and isthmus calculated both before and after final debridement . Statistical analysis was completed by using a repeated- measures analysis of variance with Tukey post hoc tests . RESULTS AND CONCLUSIONS The results showed no statistically significant difference in canal or isthmus cleanliness among the 4 groups , but there was a statistically significant difference ( P < .001 ) in canal cleanliness between the 1-mm level versus the 3-mm and 5-mm levels for all of the groups
Inconclusive results were reported about the cleaning and disinfection accomplished by the two irrigation methods .
There is insufficient evidence to cl aim general superiority of any one of these methods .
The aim of this study was to systematic ally review and critically analyse the published data on the treatment outcome ( primary outcome ) and on the  cleaning and disinfection of root canals  ( secondary outcomes ) achieved by negative pressure irrigation as compared to syringe irrigation .