title: Apical extrusion of intracanal debris and irrigant following use of various instrumentation techniques.
abstract: OBJECTIVE
  The purpose of this study was to compare in vitro the amount of debris and irrigant extruded apically from extracted teeth, using manual technique and crowndown pressureless technique by K3, RaCe, and FlexMaster instruments.
  
  
  METHODS
  Sixty human single-rooted mandibular premolar teeth were randomly assigned to 4 groups, 15 teeth each. The teeth in 4 groups were instrumented until the working length with RaCe, K3, FlexMaster, and K-type stainless steel instruments respectively. Debris and irrigant extruded from the apical foramen were collected into vials and the amounts were determined. The data obtained were analyzed using Kruskal-Wallis 1-way analysis of variance and Mann-Whitney U tests, with alpha = 0.05 as the level for statistical significance.
  
  
  RESULTS
  No statistically significant difference was observed among the groups in terms of debris extrusion (P > .05). On the other hand, a statistically significant difference was observed between K3 and manual technique groups in terms of irrigant extrusion (P < .05). The difference between other groups was not statistically significant (P > .05).
  
  
  CONCLUSIONS
  Based on the results, all instrumentation techniques produced extruded debris and irrigant; however, the engine-driven nickel-titanium systems were associated with less apical extrusion and irrigant.
authors.affiliation: Department of Endodontics, School of Dentistry, Cumhuriyet University, Sivas, Turkey.
authors.forename: Alper
authors.initials: A
authors.lastname: Kuştarci
authors.forename: Kerem Engin
authors.initials: KE
authors.lastname: Akpinar
authors.forename: Kürşat
authors.initials: K
authors.lastname: Er
mesh_terms: D000704:Analysis of Variance; D001641:Bicuspid; D003722:Dental Alloys; D003762:Dental Instruments / Q000009:adverse effects*; D005119:Extravasation of Diagnostic and Therapeutic Materials / Q000209:etiology*; D006801:Humans; D009532:Nickel; D012388:Root Canal Irrigants; D018915:Root Canal Preparation / Q000009:adverse effects* / Q000295:instrumentation* / Q000379:methods; D016369:Smear Layer; D012973:Sodium Hypochlorite; D018709:Statistics, Nonparametric; D014025:Titanium; D019227:Tooth Apex
chemical_list: D003722:Dental Alloys; D012388:Root Canal Irrigants; C040654:titanium nickelide; D009532:Nickel; D014025:Titanium; D012973:Sodium Hypochlorite