Retreatability of calcium silicate-based sealers based on micro-computed tomographic evaluation - A systematic review

Introduction: Endodontic retreatment procedures with calcium silicate-based sealers (CSS) have been receiving greater credibility in clinically challenging situations. The objective of this systematic review was to analyze the published in vitro studies for the retrievability of CSS in comparison to resin-based sealers evaluated using microcomputed tomography (micro-CT) in terms of the volume of the residual root canal filling materials, time taken, efficacy of the solvent, and different systems used during the retreatment procedure. Methods: The study protocol was registered in the International Prospective Register of Systematic Reviews and conducted in adherence to PRISMA 2020 checklist. Accordingly, an electronic literature search was done to identify studies published in English language, within the time frame from January 2004 to June 2024. The search was conducted through popular databases including PubMed (Medline - National Library of Medicine), Scopus (Science Direct), EMBASE and Google Scholar following the inclusion and exclusion criteria answering the research question in focus. Results: After thorough scrutiny, 15 studies qualified for the systematic review. Following retreatment, in all of the studies pre-treatment working length was achieved, with both the types of endodontic sealers. However, none of the micro-CT studies reported complete removal of endodontic filling material from the root canals. Irrespective of the sealer type used, within each root canal, apical third had the greatest amount of remaining filling material, followed by the middle and coronal thirds. Conclusions: Retreatment of canals obturated with bioceramic sealers is feasible in most cases using traditional instruments and techniques. Active irrigation and supplemental mechanical removal, which employs lasers, XPFinisher, and ultrasonics, adds advantage to maximize material removal.