Restor Dent Endod.  2013 May;38(2):93-97. 10.5395/rde.2013.38.2.93.

Retrieval of a separated nickel-titanium instrument using a modified 18-guage needle and cyanoacrylate glue: a case report

  • 1Department of Conservative Dentistry, Dr. Z. A. Dental College, Aligarh Muslim University, Aligarh, India.


During root canal preparation procedures, the potential for instrument breakage is always present. When instrument breakage occurs, it leads to anxiety of the clinician and as well as a metallic obstruction of the canal which hinders further cleaning and shaping. Separated instruments must always be attempted for retrieval and if retrieval is not possible bypass should be tried. With the increased use of nickel-titanium (NiTi) instruments the incidence of separated instruments has increased. A considerable amount of research has been done to understand the various factors related to the fracture of NiTi instruments to minimize its occurrence. This paper presents a review of the literature regarding the fracture of NiTi instruments and also describes a case report showing the use of a modified 18-guage needle and cyanoacrylate glue to retrieve a separated NiTi instrument from the mesiolingual canal of a mandibular first molar.


Instrument; Retrieval; Root canal; Separated instrument

MeSH Terms

Dental Pulp Cavity
Root Canal Preparation


  • Figure 1 (a) Radiograph showing separated instrument; (b) Radiograph showing dentine surrounding the coronal end of the separated fragment removed with GG drill.

  • Figure 2 An 18-guage needle, modified by cutting with a carborandum disc from the tip to transform it into a microtube.

  • Figure 3 Separated instrument fragment removed adhered to the microtube.

  • Figure 4 (a) Radiograph confirming instrument removal; (b) Working length reconfirmed.

  • Figure 5 (a) Post-obturation radiograph; (b) Two-year follow up radiograph.

Cited by  1 articles

The top 10 most-cited articles on the management of fractured instruments: a bibliometric analysis
Lora Mishra, Hyeon-Cheol Kim, Naomi Ranjan Singh, Priti Pragati Rath
Restor Dent Endod. 2019;44(1):.    doi: 10.5395/rde.2019.44.e2.


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