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25Dental Tribune Middle East & Africa Edition | September-October 2014 Dr Ala Al-Dameh is Assistant Professor of Endodontics at Dubai College of Dental Medi- cine. About The Author Figure 1. Separation of a second instrument while attempting to remove the first separated instrument is not uncommon. Figure 2. Steiglitz forceps for removal of accessible fragments. Figure 3. A selection of ultrasonic tips with contra-angled designs & different lengths to enable removal of dentine from the root canal system and facilitate instrument removal . Management of Intracanal Separated Instruments By Dr Ala Al-Dameh O ccasionally during non- surgical root canal ther- apy, an instrument will separate in a canal system, hin- dering cleaning and shaping procedures and blocking ac- cess to the canal terminus. Any instrument may break-steel, nickel-titanium (NiTi), hand, or rotary. Separation rates of stainless steel (SS) instruments have been reported to range be- tween 0.25% and 6.0%1 , while separation rates of NiTi rotary instruments have been report- ed to range between 1.3% and 10.0%2 . Even with experienced clinicians this problem can occur and is a source of disap- pointment for both clinicians and patients. There are many factors that contribute to instrument sep- aration. The most common causes are improper use, limi- tations in physical properties, inadequate access, root canal anatomy and possibly manu- facturing defects3 . The purpose of this article is to summarize current understanding of the impact of separated instru- ments on prognosis, treatment options, and to make recom- mendations for their manage- ment. Prognosis The prognostic impact of a re- tained separated instrument on endodontic treatment and re- treatment has been investigat- ed in only a few studies, most of which are based on small num- bers of cases. Recent clinical studies document that progno- sis is not significantly affected by the separated instrument itself. Prognosis depends on how much undebrided and un- obturated canal apical to and including the instrument re- mains. The outcome is better if the canal was instrumented to the later stages of preparation when the separation occurs4 . If vital and uninfected pulp tissue was present, and there was no apical periodontitis, the presence of the separated in- strument should not affect the prognosis5 . If the instrument can be removed without caus- ing iatrogenic complications such as perforations, ledg- ing, extrusion of the fragment through the apex, or excessive weakening of tooth structure (Figure 1), the prognosis will not be affected. However, if the instrument cannot be removed or bypassed in a tooth with a necrotic infected pulp and api- cal periodontitis, the prognosis will be uncertain. These cases should be followed closely and if symptoms persist, apical sur- gery or extraction should be considered4 . Treatment Options A clinician could either (1) at- tempt to remove the separated instrument, (2) bypass it, (3) prepare and obturate to the segment. Before a clinician makes the decision to remove a separated instrument, he/she should ensure the availability of and successful handling of the required armamentarium. The surgical operating micro- scope is an invaluable tool in helping to remove separated instruments. It increases vis- ibility by the use of magnifica- tion and light and increases the efficiency and safety of almost all techniques used. Various methods have been proposed for removing sepa- rated instruments. Chemical solvents have historically been used to achieve intentional corrosion of metal objects6 . If the separated instrument is clinically visible in the coronal access and there is sufficient space for a hemostat or Stieglitz Pliers (Henry Schein, Melville, NY) (Figure 2), these should be used to remove the fragment through the access cavity prep- aration. In more recent times, specialized devices and tech- niques have been introduced. Masserann instruments, wire loop techniques, hypodermic surgical needles, extractors, the Post Removal System (Syb- ronEndo), the EndoPlus System (EndoTechnic, San Diego, CA) and the Instrument Removal System (DENTSPLY Tulsa Dental, Tulsa, OK) have all shown limitations7 . Ultrasonic instruments have been shown to be very effective for the removal of separated in- struments8 . Nevertheless, suc- cessful removal relies on fac- tors such as the position of the instrument in relation to the canal curvature, depth within the canal, and the type of the separated instrument7 . To re- move the instrument predict- ably, the clinician must create straight-line coronal radicular access. Ultrasonics tips can then be used to create a staging platform to trephine dentine around the fragment (Figure 3). With this trephining action and the vibration being trans- mitted to the fragment, the latter often begins to loosen and occasionally it will ap- pear to jump out of the canal3 . Care must be taken, however, to avoid complications such as ultrasonic separation or root perforation. Clinical Recommendations and Conclusions Removing a separated instru- ment requires skilled use of the operating microscope and is generally considered within the remit of the endodontic spe- cialist. Attempts at removing a sepa- rated instrument can be estab- lished as a first management option if the instrumented sep- arated at an early stage of root canal cleaning and shaping, and the fragment is accessible. If the fragment is at or beyond the canal curve, retrieval is much less predictable. As re- moval is associated with con- siderable risk, by passing the instrument should be consid- ered. If retrieval attempts prove unsuccessful without fur- ther compromising the tooth, and the tooth continues to be symptomatic or fails to show any signs of healing at recall reviews, alternative treatment options such as apical surgery, intentional replantation or ex- traction can always be consid- ered. In all situations, manage- ment options should always be thoroughly discussed with the patient and the definite treat- ment plan should take into consideration factors that will affect prognosis (especially the presence of periapical pathol- ogy) and should be towards the patient’s best interest. References 1. Spili P, Parashos P, Messer HH. The impact of instrument frac- ture on outcome of endodontic treatment. J Endod 2005; 31: 845- 50 2. Madarati A, Hunter M, Dum- mer P. Management of intracanal separated instruments. J Endod 2013; 39: 569-581 3. Bachall JK, Carp S, Miner M, Skidmore L. The causes, preven- tion, and clinical management of broken endodontic rotary files. Dent Today 2005; 24. 74, 76, 78- 80. 4. Torabinejad M, Walton RE, editors: Priniciples and practice of endodontics, ed 4, St. Louis, 2009, Saunders. 5. Crump MC, Nakatin E: Re- lationship of broken root canal instruments to endodontic case prognosis: a clinical investiga- tion. J Am Dent Assoc 1970; 80: 1341-7 6. Hulsmann M. Methods for re- moving metal obstructions from the root canal. Endod Dent Trau- matol 1993; 9: 223-37 7. Parashos P, Messer HH. Rotary NiTi instrument fracture and its consequences. J Endod 2006; 32: 1031-43 8. Ruddle CJ. Nonsurgical re- treatment. J Endod 2004; 30: 827- 45