[Challenges and clinical strategies for endodontic microsurgery in the posterior maxillary region]

The posterior maxillary region presents substantial challenges in endodontic microsurgery owing to its unique anatomical position and intricate root canal anatomy. Three factors contribute to this complexity: first, the posterior location and limited surgical field, compounded by prominent buccal and palatal contours, severely limit visual clarity and operative maneuverability. Second, the complex root canal anatomy‒particularly isthmuses and the second mesiobuccal canal‒increases the difficulties and risks associated with root-end resection and retrograde obturation. Third, the intimate proximity of root apices to the maxillary sinus floor poses substantial risks of sinus membrane perforation and subsequent complications. To address these challenges, we propose a systematic analytical approach and refine operational strategy throughout the entire surgical procedure, aiming to thoroughly eliminate the source of infection, achieve reliable apical sealing, maximize tooth structure preservation, and ensure the safety of adjacent critical structures. This study systematically analyzes the three major challenges and offers corresponding surgical strategies and recommendations for risk prevention and control, to standardize practice and improve treatment outcomes in maxillary posterior endodontic microsurgery.