title: Not all electronic foramen locators are accurate in teeth with enlarged apical foramina: an in vitro comparison of 5 brands.
abstract: BACKGROUND
  Electronic working length measurement during root canal treatment in teeth with enlarged apical foramina is a challenge. The aims of this in vitro study were (1) to assess the influence of foramen widening on the accuracy of 5 different electronic foramen locators (EFLs) and (2) to compare the accuracy of EFLs in different foramen sizes.
  
  
  METHODS
  The following EFLs were used: MiniApex, Root ZXII, iPex, Propex II, and Elements Apex Locator. Each EFL was used in 3 groups (n = 20) of extracted teeth, with foramen diameters of 0.27 mm (G27), 0.47 mm (G47), and 0.72 mm (G72). Working length was measured according to manufacturer's instructions and compared with visual measurements (control method). Results were classified as accurate (equal or differences ≤ 0.05 mm) or inaccurate (differences > 0.5 mm).
  
  
  RESULTS
  In G27, all EFLs yielded accurate findings (intragroup reliability; Fisher exact test, P < .05), compared with only MiniApex, Root ZXII, and Elements Apex Locator in G47 and G72. MiniApex, Root ZXII, and Elements Apex Locator were similarly accurate regardless of foramen size. iPex and Propex II were the least accurate among the devices tested, and foramen diameter influenced their accuracy, with greater diameters yielding poorer EFL performance.
  
  
  CONCLUSIONS
  Foramen diameter did not influence the accuracy of MiniApex, Root ZXII, and Elements Apex Locator EFLs. iPex and Propex II showed decreased accuracy as foramen size increased.
authors: Department of Endodontics, School of Dentistry, Universidade Santa Cecilia, Santos, São Paulo, Brazil.
authors: Eduardo
authors: E
authors: Akisue
authors: Private practice, São Bernardo do Campo, São Paulo, Brazil.
authors: Simone Domingues
authors: SD
authors: Gratieri
authors: Department of Restorative Dentistry, School of Dentistry, Universidade Luterana do Brasil (ULBRA), Canoas, Rio Grande do Sul, Brazil.
authors: Fernando Branco
authors: FB
authors: Barletta
authors: Department of Cosmetic Dentistry, School of Dentistry, Universidade de São Paulo (USP), São Paulo, São Paulo, Brazil.
authors: Celso Luiz
authors: CL
authors: Caldeira
authors: Graduate Program in Dentistry, ULBRA, Canoas, Rio Grande do Sul, Brazil. Electronic address: regrazziotin@gmail.com.
authors: Renata
authors: R
authors: Grazziotin-Soares
authors: Department of Endodontics, School of Dentistry, Universidade Santa Cecilia, Santos, São Paulo, Brazil; Department of Cosmetic Dentistry, School of Dentistry, Universidade de São Paulo (USP), São Paulo, São Paulo, Brazil.
authors: Giulio
authors: G
authors: Gavini
mesh_terms: D002138:Calibration; D003786:Dental Pulp Cavity / Q000033:anatomy & histology*; D055615:Electrical Equipment and Supplies / Q000592:standards* / Q000706:statistics & numerical data; D004867:Equipment Design / Q000592:standards; D006801:Humans; D008422:Materials Testing; D009811:Odontometry / Q000295:instrumentation* / Q000592:standards; D015203:Reproducibility of Results; D018915:Root Canal Preparation / Q000295:instrumentation* / Q000592:standards; D019227:Tooth Apex / Q000033:anatomy & histology*
keywords: Apical foramen; apical widening; electronic apex locator; file size; root canal instrumentation; root length determination