title: Assessment of apically extruded debris produced by the self-adjusting file system.
abstract: BACKGROUND
  This study was designed to quantitatively evaluate the amount of apically extruded debris by the Self-Adjusting-File system (SAF; ReDent-Nova, Ra'anana, Israel). Hand and rotary instruments were used as references for comparison.
  
  
  METHODS
  Sixty mesial roots of mandibular molars were randomly assigned to 3 groups (n = 20). The root canals were instrumented with hand files using a crown-down technique. The ProTaper (Dentsply Maillefer, Ballaigues, Switzerland) and SAF systems were used according to the manufacturers' instructions. Sodium hypochlorite was used as an irrigant, and the apically extruded debris was collected in preweighted glass vials and dried afterward. The mean weight of debris was assessed with a microbalance and statistically analyzed using 1-way analysis of variance and the post hoc Tukey multiple comparison test.
  
  
  RESULTS
  Hand file instrumentation produced significantly more debris compared with the ProTaper and SAF systems (P < .05). The ProTaper system produced significantly more debris compared with the SAF system (P < .05).
  
  
  CONCLUSIONS
  Under the conditions of this study, all systems caused apical debris extrusion. SAF instrumentation was associated with less debris extrusion compared with the use of hand and rotary files.
authors.affiliation: Department of Endodontology, Grande Rio University, Duque de Caxias, Rio de Janeiro, Brazil. Electronic address: endogus@gmail.com.
authors.forename: Gustavo André
authors.initials: GA
authors.lastname: De-Deus
authors.affiliation: Department of Endodontology, Grande Rio University, Duque de Caxias, Rio de Janeiro, Brazil.
authors.forename: Emmanuel João
authors.initials: EJ
authors.lastname: Nogueira Leal Silva
authors.affiliation: Department of Endodontology, Grande Rio University, Duque de Caxias, Rio de Janeiro, Brazil.
authors.forename: Edson Jorge
authors.initials: EJ
authors.lastname: Moreira
authors.affiliation: Department of Endodontology, Grande Rio University, Duque de Caxias, Rio de Janeiro, Brazil.
authors.forename: Aline
authors.initials: A
authors.lastname: de Almeida Neves
authors.affiliation: Department of Endodontology, Rio de Janeiro State University, Rio de Janeiro, Brazil.
authors.forename: Felipe Gonçalves
authors.initials: FG
authors.lastname: Belladonna
authors.affiliation: Department of Endodontology, Grande Rio University, Duque de Caxias, Rio de Janeiro, Brazil.
authors.forename: Michele
authors.initials: M
authors.lastname: Tameirão
mesh_terms: D003722:Dental Alloys / Q000737:chemistry; D003786:Dental Pulp Cavity / Q000473:pathology*; D004867:Equipment Design; D006801:Humans; D008963:Molar / Q000473:pathology; D009532:Nickel / Q000737:chemistry; D011897:Random Allocation; D012388:Root Canal Irrigants / Q000627:therapeutic use; D018915:Root Canal Preparation / Q000295:instrumentation*; D012399:Rotation; D016369:Smear Layer / Q000145:classification / Q000473:pathology*; D012973:Sodium Hypochlorite / Q000627:therapeutic use; D007507:Therapeutic Irrigation / Q000379:methods; D014025:Titanium / Q000737:chemistry; D019227:Tooth Apex / Q000473:pathology*
chemical_list: D003722:Dental Alloys; D012388:Root Canal Irrigants; C040654:titanium nickelide; D009532:Nickel; D014025:Titanium; D012973:Sodium Hypochlorite
keywords: Anatomy; cone-beam computed tomography imaging; mandibular molars; morphology; root canal