Instrument Retrieval in Endodontics: A Literature Review

Abstract

Instrument separation poses a notable challenge in endodontic therapy, with occurrence rates between 2% and 6%. While a separated instrument does not automatically equate to treatment failure, it can hinder complete debridement and obturation, which might result in bacterial survival and inflammatory responses. This review of the literature examines the various factors that contribute to instrument separation, including mechanical fatigue, instrument design, and clinical aspects such as canal curvature and operator experience and evaluates the current methods available for retrieving these instruments. These methods encompass mechanical techniques (e.g., ultrasonics, retrieval kits), chemical solutions (e.g., EDTA), and surgical procedures when non-surgical methods are ineffective. Advances in technology, including improved magnification, ultrasonic devices, and platforms like Endo Rescue, have enhanced retrieval success rates. Additionally, bioceramic materials and CAD/CAM-assisted restorations provide better outcomes following retrieval. Nonetheless, challenges persist, including the risk of root perforation, tooth fractures, and the presence of retained fragments. The success of the retrieval process depends on the position and size of the fragment, the anatomy of the canal, and the clinician's expertise. Research indicates that the presence of a retained instrument may not significantly impact prognosis when apical periodontitis is absent, though outcomes worsen in cases with infection. Ultimately, the clinician’s expertise, proficiency, and the integration of modern tools are crucial for effective management. Ongoing research and continuous professional development are vital for enhancing retrieval methods and improving patient results in endodontics.

Keywords:  Instrument separation, Endodontic complications, Fractured file removal, Ultrasonic retrieval, Nickel-titanium instruments, Root canal anatomy, Endodontic retreatment, Masserann kit