Retrieval of Intracanal Broken Instruments Using the Microsonic Technique

Objectives: One of the most frustrating complications in endodontic therapy is the intracanal breakage of endodontic instruments. The aim of this study was to evaluate the clinical effect of microsonic technique on removal of intracanal broken instruments. Methods: 44 teeth with 47 intracanal broken instruments, which could not be successfully managed by conventional methods, were endodontically retreated with ultrasonic instruments under the operating microscope. The success rate was calculated and cases were reviewed 5 to 19 months after retreatment. Results: 34(34/47) broken instruments in 33(33/44) teeth were complelety removed with a success rate of 75%. Root canal preparation and obturation were subsequently performed on these teeth. 13 separated instruments in 11 teeth, however, could not be eliminated from the canals. For these teeth, canal spaces coronal to the intracanal obstructions were cleaned, shaped and obturated. Root canal perforation or vertical fracture was not occurred. None of these teeth showed periapical deterioration in the follow-up examination. Conclusions: The combined use of operating microscope and ultrasonic instruments in endodontic retreatment enriched the way of managing complicated cases with intracanal broken instruments.