Separated Instrument Management as a Procedural Accident in Endodontics Using the EDTA (C10H16N2O8) Aided Bypassing Technique and the Ultrasonic Removal Method. An in vitro Study

Abstract

Fracture of endodontic files can be considered a real concern during root canal treatment. This procedural accident is caused both by overusing instruments due to economic reasons and using an incorrect technique in root canals with difficult anatomy. A broken endodontic file does not always regard the treatment as a failure. Frequently the broken fragment can be bypassed, and the root canal treatment completed. In other cases, when the file is separated in a tooth with associated apical disease, its retrieval using ultrasonic tips is advised. Separation of a file usually occurs in molars, mainly in the mesiobuccal canal due to major curvature, poor access or small diameter. Our research was conducted to determine the in vitro efficiency of the ultrasonic removal method and the bypass technique by using 40 extracted molars with moderately curved roots. #25 K-files were deliberately broken in the middle third of mesiobuccal root canals after making a small excavation in the apical third of their active part. The results showed a significantly higher success rate of the ethylenediaminetetraacetic acid (EDTA) aided bypassing technique compared to the ultrasonic removal method.

Separated Instrument Retrieval using Ultrasonic Vibration and the Braiding Technique: A case report

“…Such mishap was reported to take place in one of two ways; torsional failure, where a continuous large load exceeding the instrument's torsional strength causes its separation, or flexural cyclic fatigue failure, where repeated cycles of small load subject the instrument to repeated compression and tension, forming cracks that propagate rapidly until the instrument separates (10). Removing separated instruments is a time-consuming process that requires much time and effort (7).…”

“…The literature provides ample evidence of the high success rate of ultrasonic vibration in removing separated instruments (6,7). However, the drawbacks of this technique include the unavoidable removal of root dentin, excessive generation of heat that could transfer to the surrounding periodontium, possible secondary fracture of the separated instrument, and probable lateral root perforation (8).…”

A Comparative Evaluation of Root Fracture Resistance of Three Techniques of Retrieval of Separated Endodontic Instruments from Curved Root Canals (An In Vitro Study)

“…The introduction of nickel-titanium (NiTi) instruments made a revolution in the scope of endodontics. The super elasticity and shape memory properties make nickel-titanium instruments more exible than stainless steel instruments (2,3). Nickel-titanium instruments provide more centered preparation inside canals so, less procedural errors (4) .…”