![]() ![]() Coronal part of the canal: removal of fractured instrument should be attempted with minimal dentin removal.ī.If bypass is impossible, obturate canal up to instrument and follow up, apical surgery should be considered. Middle part of the canal: one should try to bypass the broken instrument.Obturation up to the fragment is recommended. Apical third of the canal: removal of the fractured file fragment should not be routinely attempted.Recommendations are the same as in vital pulp cases: Instrument fractured after major cleaning and shaping- canal is prepared to at least size #30. The stage of shaping and cleaning at the moment of file breakage influences our decisions-Ī. Removal of a fractured instrument should be attempted with minimal dentin removal, different types of grasping equipment can be used Instrument fractured in coronal part of canal. Bypass with afterward hand files shaping up to #30. 19 If the broken instrument prevents effective disinfection and the apical lesion does not heal or a new lesion is developed, apical surgery can be used without sacrificing peri-cervical dentin.įigure 4. 19 Nowadays, total sterilization of canals is still a utopic goal. Periapical healing takes place if during Endodontic treatment disinfection decreases microbial load beneath the specific threshold. 18 We often see teeth with fractured instruments that were treated many years ago and have no clinical or radiologic signs of periapical inflammation (Fig 2). 17 A broken file by itself does not induce inflammation. 16 The most common cause of periapical lesions is intra-radicular infection. The goal of endodontics is to treat or prevent apical periodontitis. Removal of healthy dentin and especially peri-cervical dentin decreases root strength and can predispose the root to vertical root fracture 11-15 (Fig1).The first principle of medicine is do not hurt your patient, please remember it. The rate of successful fragment removal is high 10 but can it be defined as endodontic treatment success? Immediate untoward results of dentin removal may be perforation or strip perforation at the danger zone 11. The use of an operative microscope to facilitate canal widening to the level of the broken fragment and its removal by ultrasonic tips and/or some type of grasping equipment is accepted worldwide. ![]() The common approach for dealing with a broken instrument is its removal. 4,6 Unfortunately, it is theoretically impossible to create nonbreaking instruments because of the fact that more flexible instruments, that are more resistant to cyclic fatigue, have been assumed to be less resistant to torsional load and vice versa. 6-7 Common reasons for fracture of rotary NiTi files are flexural and/or torsional fatigue. 3-5 The single use of rotary NiTi instruments reduces the chance of breakage to 0.9% but does not prevent the chance of fracture entirely. 1 Stainless steel instrument fracture can be prevented mostly by discarding instruments that show signs of metal fatigue 2 however, NiTi instrument separation can happen without any sign of fatigue. The reported frequency rate for fractured instruments varies from 0.7% to 6% of cases. The fracture of endodontic instruments during root canal treatment is a complication every endodontist must have to deal with. ![]()
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