Introduction: In the context of endodontic treatment, mainly endodontic irrigation, endodontic therapy promotes the removal of debris from the pulp tissue, seeking cleaning and asepsis against various microorganisms. Objective: Carried out a systematic review of the main methods and clinical outcomes of irrigation in endodontics, presenting information on the effectiveness and biocompatibility on the dentin surface. Methods: The present study followed by a systematic review (PRISMA). The search strategy was performed in the PubMed, Scielo, Cochrane Library, Web of Science and Scopus, and Google Scholar databases. Results and Conclusion: The success of endodontic treatment depends on eradicating microbes (if present) from the root canal system and preventing reinfection. In research comparing the effectiveness of EDTA 17% maleic acid to 7%, and observed a greater effectiveness of maleic acid in removing the smear layer from the apical third of single-adicular human teeth. When compared to maleic acid, 5% of 17% EDTA proved to be equally effective. Irrigation with 70% ethanol showed a significantly higher percentage of clean root canal walls and greater depth of clean dentinal tubules when compared to irrigation with 2.5% sodium hypochlorite and 17% EDTA-T. The volume of irrigants and agitation act to reduce the microhardness of dentin in the root canal. The smallest reduction in hardness was found in the EDTA + NaOCl association, which can be explained by the fact that one substance has the power to neutralize the other. An alternative EDTA (EDTA - T) to the conventional one was studied and showed good results to remove the smear layer and a good antimicrobial action, but showed a greater potential to generate inflammation than conventional 17% EDTA and 10% citric acid. Finally, one study showed that PUI with continuous irrigation and SAF were more effective than EndoVac and the conventional syringe in removing the drug Ca(OH)2 from a standardized artificial groove in the apical part of the root canal.