Accuracy of the electronic apex locator, tactile, and radiographic methods in working length determination

Frank Osei-Bonsu; Patrick Caldicock Ampofo; Ebenezer Anno Nyako; Sandra Ama Hewlett; Victoria Afi Buckman; Akua Boakyewa Konadu; Paa-Kwesi Blankson; Tom Ndanu

doi:10.4103/jcd.jcd_45_23

Accuracy of the electronic apex locator, tactile, and radiographic methods in working length determination

J Conserv Dent. 2023 May-Jun;26(3):311-315. doi: 10.4103/jcd.jcd_45_23. Epub 2023 May 16.

Authors

Frank Osei-Bonsu^{1

2}, Patrick Caldicock Ampofo², Ebenezer Anno Nyako², Sandra Ama Hewlett², Victoria Afi Buckman², Akua Boakyewa Konadu², Paa-Kwesi Blankson³, Tom Ndanu⁴

Affiliations

¹ Dental Department, Greater Accra Regional Hospital, Accra, Ghana.
² Department of Restorative Dentistry, University of Ghana Dental School, Accra, Ghana.
³ Department of Oral and Maxillofacial Radiology, University of Ghana Dental School, Accra, Ghana.
⁴ Department of Community and Preventive Dentistry, University of Ghana Dental School, Accra, Ghana.

Abstract

Background: Determination of working length (WL) is necessary for the successful outcome of root canal treatment (RCT). Common methods in WL determination include tactile, radiographic, and electronic apex locators (EAL).

Aim: The aim of this study was to compare three methods of WL determination to the actual visualization of the apical constriction (AC).

Materials and methods: Consecutive patients with indications for extraction of single-rooted single canal teeth at the University of Ghana Dental School clinic were randomly assigned to three groups. In-vivo root canal WL was determined by tactile sensation, digital radiography, and a 5^th generation EAL (Sendoline S5). Files were cemented in the canals after the in-vivo measurements. The apical 4-5 mm of the roots was trimmed to expose the inserted files and the AC. Actual WL, as determined by visualization of the AC, was done using a digital microscope. Different WLs were then compared for the various groups, and the mean actual canal lengths were reported.

Results: EAL accurately predicted the AC in 31 (96.9%) teeth, while the digital radiographic and tactile sensation methods accurately predicted the constriction in 19 (59.4%) and 8 (25%) teeth, respectively, in the study population. The mean working canal lengths for single-rooted teeth showed no observable difference among sexes, age categories, and side of the jaw.

Conclusion: The EAL provided more reliable and accurate WL measurements for single-rooted teeth among Ghanaians, compared to digital radiography and tactile methods.

Keywords: Apical constriction; electronic apex locator; root canal treatment; tactile sensation; working length.