Machine-assisted Agitation Reduces Postoperative Pain during Root Canal Treatment: A Systematic Review and Meta-analysis from Randomized Clinical Trials

Published:March 01, 2019DOI:


      • The association between postoperative pain and irrigation dynamics was assessed.
      • Machine-assisted irrigation resulted in less pain at 24 and 48 hours.
      • The quality of evidence was graded as “moderate” quality.



      This systematic review and meta-analysis aimed to assess whether machine-assisted agitation resulted in less postoperative pain (PP) compared with syringe irrigation with needle alone in adult patients undergoing root canal treatment.


      A literature search was performed in 3 electronic databases for articles published before August 2018. Randomized clinical trials published in English that compared PP between machine-assisted agitation and syringe irrigation with needles as part of nonsurgical root canal treatment were included. Two authors were independently involved in the article selection process, data extraction, and assessment of the quality of included studies using the revised Cochrane risk of bias tool. The pooled effect estimates of the standardized mean difference (SMD) between machine-assisted agitation and syringe irrigation with needle was calculated by a random effects–modeled meta-analysis. A subgroup meta-analysis was performed. The quality of evidence was evaluated by the Grading of Recommendations, Assessment, Development and Evaluations approach.


      Six studies were included for systematic review. Meta-analysis was performed using 3 studies and showed that machine-assisted agitation resulted in less PP compared with syringe irrigation with needle at 24 hours (SMD = −0.73; 95% confidence interval, −1.04 to −0.42; I2 = 30.6%) and 48 hours (SMD = −0.60; 95% CI, −0.85 to −0.35; I2 = 0%). The quality of evidence by Grading of Recommendations, Assessment, Development and Evaluations for the PP outcomes (24 hours and 48 hours) was graded as “moderate” quality.


      Machine-assisted agitation reduced PP compared with syringe irrigation with needles in nonsurgical root canal treatment. Future clinical trials are needed to support the result of this review.

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