Objective: To examine the effect of a variety of irrigation systems on the removal of root canal Ca (OH)2
residues through meta-analysis and systematic review. Material and Methods: A search of relevant articles
was systematically performed on databases of Medline, PubMed, Cochrane Library, Embase, ISI, and
Google Scholar published from 2013 to 2019. Electronic title management was carried out by EndNote X9
software. Searches were based on the main keywords of “Irrigation Systems”, “Calcium Hydroxide”,” Root
Canal”, “Self-adjusting File OR SAF”, “Conventional Irrigation”, “EndoVac System”, “Ultrasonic Irrigation”
and “YAG Laser”. Results: The studies investigated were found to lack any standardization concerning the
irrigation method used or the measurement of outcomes; for instance, different studies used 5 or 10 mL of
2.5% NaOCl, or 5 mL of 5.25% NaOCl, or 0.5 mL, 3 mL and 10 mL of 17% EDTA. Conclusion: The
effective techniques for the removal of root canal Ca(OH)2 were PUI, and SAF approaches.
