Breaking the Barrier: CPR in Action Conservative Canal Preparation & Ultrasonic Retrieval in Molar Canals - A Case Series

AbstractIntroduction: Instrument separation during root canal treatment is a recognized procedural complication that may compromise canal debridement and treatment outcome. Management depends on the location of the fragment, with coronal third fragments showing higher success rates for conservative approaches such as bypass and ultrasonic retrieval.Case Presentation: Two clinical cases with separated instruments in the coronal third of molar canals are presented. Both patients had a history of previously initiated root canal treatment.Radiographic examination confirmed the presence of fractured instruments obstructing canal access. After achieving isolation and access refinement, bypass was successfully performed using #8 and #10 K-files to establish canal patency and glide path. This was followed by ultrasonic activation using the Endo-X ultrasonic system under continuous sodium hypochlorite irrigation, which facilitated safe retrieval of the fragments. Subsequent biomechanical preparation was completed using rotary instrumentation, followed by obturation and post-endodontic restoration.Conclusion: The combination of bypass technique and ultrasonic retrieval provides a conservative, effective, and predictable approach for managing separated instruments in the coronal third. This method preserves radicular dentin and enables successful completion of endodontic therapy.