Retrograde Filling Materials in Endodontic Surgery: What Is the Gold Standard? A Systematic Review

There is no clear consensus on the optimal retrograde filling material for endodontic surgery, with uncertainty regarding long-term comparative performance among contemporary options. This systematic review aimed to determine which retrograde filling material provides the best long-term clinical and radiographic outcomes in endodontic microsurgery. Following PRISMA guidelines, a systematic search of PubMed/MEDLINE, Scopus, Cochrane Library, and BioMed Central was conducted up to 30 January 2026. Randomized controlled trials (RCTs) with a minimum 12-month follow-up comparing retrograde materials in endodontic surgery were included. Study selection, data extraction, and risk-of-bias assessment (Cochrane RoB 2 tool) were performed by different reviewers. It was not possible to perform a meta-analysis due to the heterogeneity of the data but only a narrative synthesis. Eleven RCTs (2002–2024), reporting on approximately 1600 teeth, were included. The overall risk of bias was moderate. Mineral trioxide aggregate (MTA) demonstrated high long-term success (typically >90%). However, in a head-to-head comparison, MTA was not statistically superior to alternatives like super-ethoxybenzoic acid (Super-EBA) or zinc oxide and eugenol-based cement reinforced with resin (IRM). A significant difference favoring MTA was consistently observed only against traditional gutta-percha techniques. No study evaluated the newest premixed bioceramic sealers beyond 12 months, while they show the best properties. Within the limitations of the current evidence, MTA, Super-EBA, and IRM are all highly effective for retrograde obturation in endodontic microsurgery, with no single material demonstrating clear superiority in long-term success. This equivalence supports clinical decision-making based on handling characteristics, cost, and surgeon preference. A critical evidence gap exists regarding the long-term (>1 year) efficacy of newer bioceramic sealers.