Effectiveness of three electronic apex locators to determine root canal working length.

  • Carolina Campillo-Cortes Faculty of Dentistry, San Luis Potosi University.
  • Héctor Flores-Reyes Faculty of Dentistry, San Luis Potosi University.
  • Claudia Dávila-Pérez Faculty of Dentistry, San Luis Potosi University.
  • Daniel Silva-Herzog Faculty of Dentistry, San Luis Potosi University.
  • Verónica Méndez-González Faculty of Dentistry, San Luis Potosi University.
  • Amaury Pozos-Guillén Faculty of Dentistry, San Luis Potosi University.


The aim of this study was to evaluate in vivo the accuracy of three electronic apex locators (EALs) in determining working length (WL) using hand files and a wear technique. Thirty two premolars that were completely formed apically and that were scheduled for extraction for orthodontic reasons from patients between ages of 15 and 20 years old were included. Electronic measurement of WL was performed using the EAL according to the manufacturer’s instructions. The following three EAL were used: A. Root ZX II; B. Raypex 5, and C. Propex II. There were significant difference (p = 0,0002) when comparing median differences among the three EAL. Statistical analysis revealed significant differences between Root ZX II vs. Raypex 5 and Root ZX II vs. Propex II (p = 0,0044; p = 0,0002), while between Raypex 5 and Propex II, there were no statistically significant differences with respect to the accuracy of the EAL in determining WL (p = 0,1087). The present findings suggest that Root ZX II presented the highest agreement rate for determining the final WL.


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How to Cite
CAMPILLO-CORTES, Carolina et al. Effectiveness of three electronic apex locators to determine root canal working length.. Journal of Oral Research, [S.l.], v. 4, n. 4, p. 249-254, june 2015. ISSN 0719-2479. Available at: <https://www.joralres.com/index.php/JOR/article/view/joralres.2015.049>. Date accessed: 01 aug. 2021. doi: https://doi.org/10.17126/joralres.2015.049.


Electronic apex locator; working length; major foramen; minor foramen; Raypex 5; Root ZX II; Propex II.