Sonic vs Ultrasonic activation of sodium hypoclorite for root canal treatments. In vitro assessment of debris removal from main and lateral canals

Aim: Aim of this study is to evaluate the efficacy of two different sonic and ultrasonic devices in the elimination of debris from artificial main and accessory canals. Methodology: Two different irrigant activator devices were tested: The sonic handpiece Endo- Activator (Dentsply Maillefer, Baillagues, Switzerland) and the ultrasonic handpiece Ultra X (Eighteeth, Changzhou Sifary Medical Technology Co., Ltd, Changzhou City, China). Two groups of 18 artificial root canals were analyzed (n=36): Main and lateral canals were embedded in a transparent resin model. Canals were filled with organic paste to simulate the necrotic pulp tissues. With both devices, irrigation was performed using 5% sodium hypoclorite and two activation times of 30 seconds each. Sodium hypochlorite was replaced every 30 seconds. After a photographic exam, debris removal was evaluated by a software and assessed in terms of percentage of cleaned canal. Means and standard deviations were calculated and data were statistically analyzed with the Anova test. Results: Under the same experimental conditions (same canal, time and irrigant), both sonic and ultrasonic devices completely cleaned the main canal. On the contrary, a statistically significant difference was noted in the debridement of lateral canals, with ultrasonic device removing more debris than the sonic one (p<0.05). No tested device was able to remove all debris from accessory canals. Conclusions: The cordless ultrasonic handpiece Ultra X used with maximum power showed significantly greater efficacy in cleaning accessory canals when compared to the sonic EndoActivator.