title: Apical extrusion of debris using ProTaper Universal and ProTaper Next rotary systems.
abstract: OBJECTIVE
  To assess and compare the amount of extruded debris after canal preparation using ProTaper Universal and ProTaper Next files.
  
  
  METHODS
  Forty extracted mandibular premolars with single canals and of similar lengths were instrumented using the ProTaper Universal F3 or the ProTaper Next X3. The extruded debris during instrumentation was collected into pre-weighed Eppendorf tubes. The tubes were stored in an incubator for 5 days. The tubes were weighed to obtain the final dry weight of the extruded debris. The amount of apically extruded debris was calculated by subtracting the initial weight of the tube from the final weight. The distribution of the data was examined using the Shapiro-Wilks test. Continuous variables were compared with an independent-samples t-test for two groups.
  
  
  RESULTS
  All specimens were associated with apical debris extrusion. The ProTaper Universal group produced a significantly greater amount of debris extrusion (P < 0.001). The lowest and highest amounts of debris for PTU and PTN groups were recorded as 0.00117-0.00165 g and 0.00017-0.00067 g, respectively.
  
  
  CONCLUSIONS
  ProTaper Next files was associated with significantly less extruded apical debris when compared to ProTaper Universal files.
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Bülent Ecevit University, Zonguldak, Turkey.
authors.forename: M M
authors.initials: MM
authors.lastname: Koçak
authors.forename: E
authors.initials: E
authors.lastname: Çiçek
authors.forename: S
authors.initials: S
authors.lastname: Koçak
authors.forename: B C
authors.initials: BC
authors.lastname: Sağlam
authors.forename: N
authors.initials: N
authors.lastname: Yılmaz
mesh_terms: D001641:Bicuspid; D003762:Dental Instruments; D004867:Equipment Design; D006801:Humans; D066298:In Vitro Techniques; D008422:Materials Testing; D018915:Root Canal Preparation / Q000295:instrumentation*; D019227:Tooth Apex / Q000601:surgery*
keywords: ProTaper Next; ProTaper Universal; apical extrusion; debris