The Effect of Passive Ultrasonic Irrigation in Comparison with other Techniques on Removing Calcium Hydroxide from Root Canals: A Systematic Review

Background and aim: Residues may remain in canal extensions and irregularities after removing the medication from root canals with a file. These residues can only have removed with irrigation. The present systematic review and meta-analysis investigated the effect of various irrigation methods on eliminating calcium hydroxide from root canals. Material and methods: A preliminary analysis included 225 articles. Two reviewers investigated all the available abstracts and titles and determined whether they were associated with the cleaning effectiveness of a variety of irrigation systems in removing calcium hydroxide. The conducted search involved the years between 2013-18. Results: The studies investigated lacked standardization concerning the irrigation method used or the measurement of outcomes; for instance, the volume or the concentration of the irrigation solution. Conclusion: Although none of the methods examined could eliminate the calcium hydroxide dressing, activation methods resulted in better calcium hydroxide dressing removal compared to using a master apical file or syringe irrigation only.