Influence of a Passive Sonic Irrigation System on the Elimination of Bacteria from Root Canal Systems: A Clinical Study

Introduction: The present investigation evaluated the ability of a new passive sonic irrigation (sonic group) system (Endo Activator) to eliminate cultivable bacteria from root canals in vivo and compared it with that of standard syringe irrigation (control group). Methods: Data were obtained by using bacteriologic sampling of root canals treated by endodontic residents. Sampling results from 1 session of treatment were then compared with results obtained after intervisit calcium hydroxide disinfection and a second session of treatment. Results: There was no significant difference in the ability of sonic group and control group to eliminate cultivable bacteria from root canals (P > .05). A second session and intervisit calcium hydroxide disinfection were able to eliminate cultivable bacteria from significantly more teeth than a single session of treatment (P < .05). Conclusions: These in vivo results strengthen the case for a multi-visit approach to the treatment of apical periodontitis. (I Endod 2010;36:1315-1318)