Fast-setting bioactive cements were developed for the convenience of retrograde fillings during endodontic microsurgery. This in vitro study aimed to investigate the effect of irrigation on the washout of relatively fast-setting materials (Biodentine, EndoCem Zr, and MTA HP) in comparison with MTA Angelus White and IRM in an apicectomy model. Washout resistance was assessed using artificial root ends. A total of 150 samples (30 for each material) were tested. All samples were photographed using a microscope, and half of them were also scanned. The samples were irrigated and immersed in saline for 15 min. Then the models were evaluated. Rinsing and immersing the samples immediately after root-end filling and after 3 min did not disintegrate the fillings made of all tested materials except Biodentine. Root-end fillings made of Biodentine suffered significant damage both when rinsing was performed immediately and 3 min after the filling. Quantitative assessment of washed material resulted in a slight loss of IRM, EndoCem MTA Zr, and MTA HP. MTA Angelus White showed a slightly greater washout. Rinsing and immersion of Biodentine restorations resulted in their significant destruction. Under the conditions of the current study, the evaluated materials, excluding Biodentine, showed good or relatively good washout resistance.

When performing an apicoectomy avoiding the microleakage is desired. That is why materials used for this procedure should be resistant to washout. Washout refers to the tendency of freshly prepared materials to disintegrate upon contact with fluids. Background/Objectives: The aim of this paper is to provide a literature review on the washout resistance of bioactive root-end filling materials. Methods: This systematic review was conducted following the PRISMA 2020 guidelines. International databases (PubMed, Google Scholar, ScienceDirect, and Wiley Online Library) were searched, and articles published in the last 20 years were selected for analysis. The following keywords were used “antiwashout”, “washout resistance”, “washout in dentistry”, “root-end filling materials”, “calcium silicate-based cements”, “bioceramic materials”. A total of 6 in vitro studies that met all the inclusion criteria were included in the analysis. The overall risk of bias was low in all six studies. Results: Most tested bioceramic materials are Endocem, Capasio, and Ceramicrete-D. Generex-A, MTA-Plus, MTA-AW, Bioaggregate, and MTA HP usually demonstrate very good washout resistance. ProRoot and MTA Angelus performed differently depending on the test; however, generally they showed good washout resistance. The Biodentine material showed significant washout, and requires further research. There is still a lack of a unified method for washout evaluation in dentistry, which makes it difficult to compare different studies. Conclusions: The study the confirmed excellent washout resistance of EndoCem, Capasio, Ceramicrete-D, Generex-A, Bioaggregate, MTA-Plus, and MTA HP. ProRoot, MTA-Angelus, and MTA Angelus White exhibited lower washout resistance. Biodentine shows poor washout resistance, and requires further research. A unified method for assessing washout would be beneficial for comparing different studies.