title: The Influence of Cervical Preflaring on the Amount of Apically Extruded Debris after Root Canal Preparation Using Different Instrumentation Systems.
abstract: BACKGROUND
  The objective of this study was to evaluate the influence of cervical preflaring on the amount of apically extruded debris after root canal preparation using different instrumentation systems.
  
  
  METHODS
  One hundred eighty human maxillary central incisors were selected and randomly divided into 12 groups (n = 15). Root canals were instrumented according to manufacturers' instructions using 2 reciprocating single-file systems (Reciproc [VDW, Munich, Germany] and WaveOne [Dentsply Maillefer, Ballaigues, Switzerland]), 3 full-sequence rotary systems (ProTaper Universal [Dentsply Maillefer], ProTaper Next [Dentsply Tulsa Dental, Tulsa, OK], and ProFile [Dentsply Maillefer]), and K-files (Dentsply Maillefer) driven by an oscillatory system with and without cervical preflaring. Bidistilled water was used as irrigant. Apically extruded debris was collected in preweighed glass vials using the Myers and Montgomery method. After drying, the mean weight of debris was determined using a microbalance. Kolmogorov-Smirnov and Levene tests followed by the Tukey post hoc test were used for statistical analysis.
  
  
  RESULTS
  K-files produced significantly more debris than all of the other systems (P < .05). For all systems, cervical preflaring reduced the amount of apically extruded debris when compared with no cervical preflaring (P < .05).
  
  
  CONCLUSIONS
  All of the systems extruded debris, irrespective of the preparation technique used (with or without cervical preflaring). Cervical preflaring was associated with the extrusion of smaller quantities of apical debris.
authors.affiliation: Department of Oral Sciences, University of Cuiabá, Cuiabá, Mato Grosso, Brazil. Electronic address: alvarohborges@gmail.com.
authors.forename: Álvaro Henrique
authors.initials: ÁH
authors.lastname: Borges
authors.affiliation: Department of Oral Sciences, University of Cuiabá, Cuiabá, Mato Grosso, Brazil.
authors.forename: Thiago Machado
authors.initials: TM
authors.lastname: Pereira
authors.affiliation: Department of Oral Sciences, University of Cuiabá, Cuiabá, Mato Grosso, Brazil.
authors.forename: Alessandra Nogueira
authors.initials: AN
authors.lastname: Porto
authors.affiliation: Department of Oral Sciences, University of Cuiabá, Cuiabá, Mato Grosso, Brazil.
authors.forename: Cyntia Rodrigues
authors.initials: CR
authors.lastname: de Araújo Estrela
authors.affiliation: Department of Oral Sciences, University of Cuiabá, Cuiabá, Mato Grosso, Brazil.
authors.forename: Fabio Luis
authors.initials: FL
authors.lastname: Miranda Pedro
authors.affiliation: Department of Oral Sciences, University of Cuiabá, Cuiabá, Mato Grosso, Brazil.
authors.forename: Andreza Maria Fábio
authors.initials: AM
authors.lastname: Aranha
authors.affiliation: Department of Oral Sciences, University of Cuiabá, Cuiabá, Mato Grosso, Brazil.
authors.forename: Orlando Aguirre
authors.initials: OA
authors.lastname: Guedes
mesh_terms: D000704:Analysis of Variance; D003722:Dental Alloys / Q000737:chemistry; D003786:Dental Pulp Cavity / Q000473:pathology; D004867:Equipment Design; D006801:Humans; D009532:Nickel / Q000737:chemistry; D011897:Random Allocation; D012388:Root Canal Irrigants; D012389:Root Canal Obturation / Q000295:instrumentation / Q000379:methods; D018915:Root Canal Preparation / Q000295:instrumentation* / 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
keywords: Cervical preflaring; debris extrusion; root canal preparation