The Dental Operating Microscope in Endodontics: A Narrative Review of Clinical Applications, Supporting Evidence, and...

The dental operating microscope (DOM) is now widely used in endodontics, but the strength of the evidence supporting its use differs between procedures. This narrative review summarizes the historical development and technical principles of the DOM, evaluates the evidence for its use in the main endodontic procedures, and outlines its limitations. A structured PubMed search covering 1981 to 2026 was supplemented by hand-searching of reference lists. The DOM combines magnification, coaxial illumination, and an upright working posture. In non-surgical root canal treatment, magnification consistently improves the detection of canal orifices, particularly the second mesiobuccal (MB2) canal of maxillary molars, and supports the management of calcified canals, complex anatomy, separated instruments, and perforations. Direct outcome data in non-surgical treatment are limited to observational studies. In vital pulp therapy and regenerative endodontic procedures, the DOM is used mainly to assess the pulp tissue and bleeding and to place materials precisely, but its independent effect on outcomes has not been tested. The strongest outcome evidence comes from endodontic microsurgery, in which a meta-analysis reported a pooled success rate of 94% with high-power magnification, compared with 88% without it, with the benefit concentrated in molars. However, two Cochrane reviews found no eligible randomized controlled trials, and a retrospective comparison of loupes and the microscope in endodontic surgery found no significant difference between them. Longer treatment time, cost, the learning curve, and restricted access in some patients are the main practical limitations. The DOM proves most advantageous when managing microscopic features that require high magnification and significantly impact the clinical outcome. Well-designed clinical trials are needed to determine whether its diagnostic advantages lead to better long-term outcomes.