Data sources Cochrane Library, Embase, LILACS, PubMed, SciELO, Scopus databases, endodontic journals and textbooks. Study selection Two independent reviewers screened the titles, abstracts and/or full-text of the both clinical or in vitro studies that used ultrasonic irrigant activation for management of teeth needing root canal therapy. Results The study included three clinical studies and 45 in vitro studies. The study reported no evidence of any benefit of ultrasonic activation over needle irrigation in improving the healing rate of apical periodontitis. While the study reported that the evidence for disinfection of the root canal was inconclusive it did show evidence of the efficacy of ultrasonic irrigation over needle irrigation when removal of pulp tissue remnants and hard tissue debris was assessed. Conclusion The study reported that it was essential that there should be more research into the antimicrobial effect on healing in periapical periodontitis when teeth are treated using ultrasonic activation.