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VOLUME 18 , ISSUE 5 ( May, 2017 ) > List of Articles


Accuracy of Working Length Determination using NovApex and Root-ZX Apex Locators: An in vitro Study

Vahid Zand, Saeed Rahimi, Paria Davoudi, Abubakr Afshang

Citation Information : Zand V, Rahimi S, Davoudi P, Afshang A. Accuracy of Working Length Determination using NovApex and Root-ZX Apex Locators: An in vitro Study. J Contemp Dent Pract 2017; 18 (5):383-385.

DOI: 10.5005/jp-journals-10024-2051

Published Online: 01-09-2017

Copyright Statement:  Copyright © 2017; The Author(s).



This ex vivo study evaluated the accuracy of the Root-ZX electronic apex locator (EAL) (J. Morita, Tokyo, Japan) and the NovApex (Forum Technologies, Rishon Lezion, Israel) in determining the working length (WL) during endodontic treatment.

Materials and methods

Forty extracted single-rooted human teeth were selected for this study. The actual WL was measured with visual technique by a size #15 k-file under magnification. Then, the canal lengths were measured electronically with both Root-ZX and NovApex apex locators within ±0.5 and ±1 mm. Mean percentage of data was analyzed between groups using paired t-test, with a statistically significant level of p < 0.05.


The accuracy of NovApex apex locator was 85% within ±0.5 mm and 92.5% within ±1 mm. The accuracy of Root-ZX apex locator was 70% within ±0.5 mm and 97.5% within ±1 mm. There was no significant difference between the accuracy of the two EALs.


Both the NovApex and Root-ZX EALs are useful for measuring the WL with high accuracy.

Clinical significance

Given the importance of accurate WL determination in the success of endodontic treatments, the accuracy of different apex locators should be evaluated.

How to cite this article

Zand V, Rahimi S, Davoudi P, Afshang A. Accuracy of Working Length Determination using NovApex and Root-ZX Apex Locators: An in vitro Study. J Contemp Dent Pract 2017;18(5):383-385.

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