title: Apically Extruded Debris after Retreatment Procedure with Reciproc, ProTaper Next, and Twisted File Adaptive Instruments.
abstract: BACKGROUND
  The aim of this study was to compare the amount of debris extruded from the apex during retreatment procedures with ProTaper Next (PTN; Dentsply Maillefer, Ballaigues, Switzerland), Reciproc (RCP; VDW, Munich, Germany), and Twisted File Adaptive (TFA; SybronEndo, Orange, CA) files and the duration of these retreatment procedures.
  
  
  METHODS
  Ninety upper central incisor teeth were prepared and filled with gutta-percha and AH Plus sealer (Dentsply DeTrey, Konstanz, Germany) using the vertical compaction technique. The teeth were randomly divided into 3 groups of 30 for removal of the root filling material with PTN, RCP, and TFA files. The apically extruded debris was collected in preweighed Eppendorf tubes. The time for gutta-percha removal was recorded. Data were statistically analyzed using Kruskal-Wallis and 1-way analysis of variance tests.
  
  
  RESULTS
  The amount of debris extruded was RPC > TFA > PTN, respectively. Compared with the PTN group, the amount of debris extruded in the RPC group was statistically significantly higher (P < .001). There was no statistically significant difference among the RCP, TFA, and PTN groups regarding the time for retreatment (P > .05).
  
  
  CONCLUSIONS
  Within the limitations of this in vitro study, all groups were associated with debris extrusion from the apex. The RCP file system led to higher levels of apical extrusion in proportion to the PTN file system. In addition, there was no significant difference among groups in the duration of the retreatment procedures.
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Ondokuz Mayis University, Samsun, Turkey.
authors.forename: Koray
authors.initials: K
authors.lastname: Yılmaz
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Ondokuz Mayis University, Samsun, Turkey. Electronic address: tahaozyurek@hotmail.com.
authors.forename: Taha
authors.initials: T
authors.lastname: Özyürek
mesh_terms: D006801:Humans; D019233:Retreatment; D012389:Root Canal Obturation / Q000379:methods; D018915:Root Canal Preparation / Q000379:methods; D012390:Root Canal Therapy / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D016896:Treatment Outcome
keywords: Apical extrusion; ProTaper Next; Reciproc; Twisted File Adaptive; retreatment