title: Comparison of apical extrusion of sodium hypochlorite using 4 different root canal irrigation techniques.
abstract: BACKGROUND
  We compared the apical extrusion of sodium hypochlorite delivered with a 27-G needle, self-adjusting file (SAF), passive ultrasonic irrigation, or the EndoVac system (SybronEndo, Orange, CA) during the instrumentation and final irrigation of root canals.
  
  
  METHODS
  Matched paired single-canal teeth were divided into 8 groups. The experimental groups were needle irrigation size #30 (NI30) and #50 (NI50), SAF size #30 (SAF30) and #50 (SAF50), passive ultrasonic irrigation size #30 (PUI30) and #50 (PUI50), and EndoVac size #30 (EV30) and #50 (EV50). Teeth were embedded in 0.2% agarose gel (pH = 7.4) containing 1 mL 0.1% m-Cresol purple (Sigma-Aldrich, St Louis, MO), which changes color at a pH level of 9.0. Root canals were irrigated with sodium hypochlorite and EDTA using 4 different techniques, and the amount of irrigant was controlled. Standardized digital photographs were taken 20 minutes after the first irrigant was used and were analyzed to determine the amount of extrusion (expressed as a percentage of total pixels).
  
  
  RESULTS
  The amounts of apical extrusion obtained in the NI30, NI50, SAF30, SAF50, PUI30, PUI50, EV30, and EV50 groups were 30% (3/10), 50% (5/10), 20% (2/10), 70% (7/10), 40% (4/10), 40% (4/10), 10% (1/10), and 10% (1/10), respectively. The overall extrusion frequency, regardless of the apical preparation size, was 40% (8/20) for needle, 45% (9/20) for SAF, 40% (8/20) for ultrasonic irrigation, and 10% (2/20) for EndoVac. Although the SAF group showed more extrusion, the percentage of pixels was significantly higher in the needle irrigation group (P < .01). The EndoVac group showed significantly lower extrusion values than the other techniques in terms of the number of teeth and pixels (P < .05 and P < .01, respectively).
  
  
  CONCLUSIONS
  The risk of apical extrusion is significantly lower with the EndoVac in comparison with the 3 other techniques.
authors.affiliation: Faculty of Dentistry, Department of Endodontics, Marmara University, Istanbul, Turkey. Electronic address: eriboz@yahoo.com.
authors.forename: Emre
authors.initials: E
authors.lastname: İriboz
authors.affiliation: Faculty of Dentistry, Department of Endodontics, Marmara University, Istanbul, Turkey.
authors.forename: Koral
authors.initials: K
authors.lastname: Bayraktar
authors.affiliation: Faculty of Dentistry, Department of Endodontics, Marmara University, Istanbul, Turkey.
authors.forename: Dilek
authors.initials: D
authors.lastname: Türkaydın
authors.affiliation: Faculty of Dentistry, Department of Endodontics, Marmara University, Istanbul, Turkey.
authors.forename: Bilge
authors.initials: B
authors.lastname: Tarçın
mesh_terms: D006801:Humans; D010486:Periapical Tissue / Q000187:drug effects*; D012388:Root Canal Irrigants / Q000494:pharmacology*; D018915:Root Canal Preparation / Q000379:methods*; D012973:Sodium Hypochlorite / Q000494:pharmacology*
chemical_list: D012388:Root Canal Irrigants; D012973:Sodium Hypochlorite
keywords: Apical extrusion; EndoVac; irrigation; passive ultrasonic irrigation; self-adjusting file