Endodontic filling material extrusion into the maxillary sinus: clinical presentation, microbiology, management, and outcomes-a systematic review.

This systematic review aimed to consolidate the clinical presentation, diagnostic and microbial findings, management approaches, and outcomes of maxillary sinus involvement caused by extruded endodontic filling materials. Searches were performed in PubMed, Web of Science, Embase, Scopus, ScienceDirect, and ProQuest up to August 2025. Observational studies reporting extrusion of filling material into the maxillary sinus, accompanied by clinical, imaging, and/or surgical descriptions, were included. Study quality was critically analyzed using the Joanna Briggs Institute tools. Of 4076 articles initially retrieved, 52 were selected for full-text reading, 39 met the inclusion criteria and were included, comprising 34 case reports and 5 case series. Maxillary first molars were the most frequently involved teeth (59%). Extrusion occurred predominantly during primary endodontic treatment. Filling material was identified in the left maxillary sinus in 21 cases (47%) and in the right maxillary sinus in 24 cases (53%). Clinical presentations ranged from incidental asymptomatic findings to severe manifestations such as acute sinusitis. In the included studies, diagnosis was established using radiographic and tomographic imaging as well as direct endoscopic evaluation. Surgical removal represented the most common definitive management approach. Clinical outcomes were predominantly favorable, with complete symptom resolution and functional recovery. Extrusion of endodontic filling materials into maxillary sinus most often involves maxillary first molars and is associated with clinically significant complications, particularly fungal sinusitis. The present findings emphasize the need for prevention, accurate diagnosis, and timely interdisciplinary care of this iatrogenic event.