|Year : 2012 | Volume
| Issue : 1 | Page : 21-24
Retrieval of separated instrument with instrument removal system
Sanjeev Kunhappan1, Neerja Kunhappan2, Sanjay Patil3, Pratibha Agrawal4
1 Department of Conservative Dentistry and Endodontics, Government Dental College, Raipur, Chhattisgarh, India
2 Department of Orthodontics, Government Dental College, Raipur, Chhattisgarh, India
3 Department of Conservative Dentistry and Endodontics, Swargiya Dada Saheb Kalmegh Dental College, Nagpur, Maharashtra, India
4 Triveni Institute of Dental Sciences, Hospital and Research Centre, Bilaspur, Chhattisgarh, India
|Date of Web Publication||23-Apr-2014|
Department of Conservative Dentistry and Endodontics, Government Dental College, Raipur, Chhattisgarh
Source of Support: None, Conflict of Interest: None
| Abstract|| |
One of the most frequent endodontic mishaps is the separation of the endodontic instrument in the root canal. The separation influences the final outcome of the root canal therapy. It interferes with the proper debridement and shaping procedures as well as with irrigation of the canal portion apical to the level of obstruction. It also prevents three dimensional fluid tight sealing of the root canal system. When an attempt to bypass such a fragment becomes difficult it is advised to retrieve it by mechanical devices. Instrument removal system (IRS) is one such a device for orthograde removal of intracanal metallic obstructions. This clinical case describes the usage of IRS for retrieval of separated instrument in the posterior teeth.
Keywords: Instrument removal system, instrument retrieval, instrument separation, modified gates glidden drills
|How to cite this article:|
Kunhappan S, Kunhappan N, Patil S, Agrawal P. Retrieval of separated instrument with instrument removal system. J Int Clin Dent Res Organ 2012;4:21-4
|How to cite this URL:|
Kunhappan S, Kunhappan N, Patil S, Agrawal P. Retrieval of separated instrument with instrument removal system. J Int Clin Dent Res Organ [serial online] 2012 [cited 2019 Apr 18];4:21-4. Available from: http://www.jicdro.org/text.asp?2012/4/1/21/131394
| Introduction|| |
Intracanal separation of endodontic instruments may hinder cleaning and shaping procedures within the root canal system. Its incidence ranges from 2% to 6% of the cases investigated.  The clinical outcome of the cases with fractured instruments depends on several factors such as: the position of the instrument in the canal, type of material, instrument size and canal anatomy. Failure in retrieval of the fractured instrument does not automatically result in failure of the case. The difficulty in the retrieval of these instruments ranges from surprisingly easy to downright impossible. While methods for obstruction bypass have been described, there are times when bypass is not possible or when complete removal of an obstruction is preferable to bypass. An attempt to bypass or retrieve the instrument should be made before leaving it and obturating the canal system. This clinical case describes the usage of IRS for retrieval of separated instrument from distal root of mandibular first molar.
| Case Report|| |
This was a case report of a 35-year-old male patient who was referred to the Department of Conservative Dentistry and Endodontics with the complaint of pain in the lower right posterior region for past 45 days and also he gave a history of root canal treatment of tooth number 36 1 month back in a private clinic. On clinical examination, the canals were found un-obturated. On inserting a file, an obstruction was encountered in the middle of the canal of distal root. A diagnostic radiograph was made, which revealed the presence of a separated instrument extending from middle to apical third of canal [Figure 1].
Since the efforts of bypassing the fragment went futile an attempt to retrieve it was made with ethylenediamene tetraacetic acid and H-file technique that proved unsuccessful. Hence, retrieval was planned using instrument removal system (IRS) The radicular straight line access to the coronal end of the fragment was obtained by funneling the root canal with sequential use of modified gates glidden drills #1 and #2 sectioned at their maximum cross-sectional to obtain a flat end [Figure 2]. IRS system was then employed for retrieval. Microtube of the IRS system was inserted into the canal with the long part of its beveled end oriented to the outer wall of the canal to "scoop up" the head of the separated instrument and guide it into the microtube [Figure 3]. Success in guiding the head of the separated instrument into the microtude could be achieved after few attempts [Figure 4]. Same color-coded screw wedge was then inserted and slided internally through the microtube's length until it contacted the separated instrument. The separated instrument was engaged by gently turning the screw wedge handle counterclockwise. A few degrees of rotation served to tighten, wedge and often displace the head of the separated instrument through the microtube window [Figure 5]. The separated instrument was removed by rotating the microtube and screw wedge assembly out of the canal in counterclockwise [Figure 6]. The microtube and the screw wedge were taken out of the canal along with the separated instrument [Figure 7] and [Figure 8].
Radiographs were taken sequentially to confirm the position of the microtube and also to make sure that finally the canal was cleared of obstruction [Figure 9]. Working length radiograph was then taken and the canals were prepared and obturated with gutta-percha using thermoplastic obturation technique.
| Discussion|| |
Separation of instruments in the canal during endodontic treatment may block access to the apical terminus. Intracanal separation of instruments usually prevents access to the apex, which impedes thorough cleaning and shaping of the root canal and thus may compromise with the outcome of endodontic treatment and reduce the chances of successful treatment.
The common causes for file separation are improper use, limitations in physical properties, inadequate access, root canal anatomy and possibly manufacturing defects.  The most ideal management of separated instruments is to prevent the occurrence in the first place. Adhering to proven concepts, integrating best strategies and utilizing safe techniques during the root canal preparation procedures will virtually eliminate the broken instrument procedural accident.  Prevention may also be greatly facilitated by thinking of negotiating and shaping instruments as disposable items. Simply discarding all instruments after the completion of each endodontic case will reduce breakage, lost clinical time and upsets. However, on occasion an instrument will break and in spite of the best existing technologies and techniques the broken file segment may not be able to be bypassed or retrieved.
Several methods and techniques have been advocated over the years for the removal of separated solid objects such as silver points and fragments of endodontic instruments.  If the coronal aspect of the fragment to be removed is accessible, it has the ability to be withdrawn from the canal by a variety of instrument systems. , Examples of such systems include Masseran™ Endodontic Kit,  the Cancellier IRS™ and the Ruddle IRS™. Recently, the use of piezoelectric ultrasonic units with their numerous compatible tips has facilitated the incremental removal of dentin surrounding separated instruments as well as their vibratory removal. 
The IRS system provides a procedural breakthrough for the removal of intracanal obstructions such as silver points, carrier-based obturators or broken file segments. The IRS system is indicated when ultrasonic efforts prove to be unsuccessful to remove broken instruments that are lodged in the straightaway portions of the root or partially around the canal curvature. ,
One of the most important factors to be considered prior to instrument retrieval by this system is to obtain a straight line access to the coronal end of the separated instrument by the use of modified gates glidden drills, #1 and #2 sectioned at their maximum cross-sectional to obtain a flat end. The objective here is to create a straight line access to the coronal aspect of the separated fragment. However, this leads to removal of a considerable amount of radicular dentin and can cause iatrogenic damage like perforation. Close inspection of pre-operative radiographs and knowledge of root anatomy is imperative before attempting the removal procedure in any tooth to ascertain the relative amount of surrounding dentin and the risk of perforation. File removal generally results in ledge formation and therefore a possible stress concentration point.  When the file is located in the middle or apical third of the root, removal procedure significantly reduces the root strength.
| Conclusions|| |
This case report attempt to address and report conventional techniques must be tried before but if they prove to be unsuccessful alternative devices should be used for the removal of broken endodontic instruments. For the successful working of the IRS system, straight-line coronal and radicular access is required to expose and subsequently visualize the coronal-most end of the broken instrument. This leads to removal of a considerable amount of radicular dentin and thus weakens the root structure.
Nonetheless, the case may be described as a success if one considers the perfect seal of the root canal system and a failure if one considers the amount of dentin lost in the retrieval process.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9]