An in vitro Comparison of Root Canal Measurement in Permanent Teeth by Electronic Apex Locator, Conventional and Digital Radiography

Abstract

ABSTRACT Introduction In endodontic treatment for permanent teeth, it is important to estimate the working length precisely. Currently, various methods are used in clinical practice for working length estimation. The objective of this study is to compare the accuracy of root canal length in permanent teeth determined by electronic apex locators, conventional and digital radiography. Materials and methods A total of 50 single rooted permanent teeth with mature apices were extracted for periodontal reasons and obtained from different sources without caries were studied. The radiographic measurements were done using paralleling technique. Electronic measurements were done next using third generation, DentAport ZX. Actual canal length of each tooth was measured using direct observation of the apical exit of the file. Measurements obtained from radiographic and electronic methods were compared to the actual tooth length. Interclass correlation coefficients and failure rate for each method and their combinations were calculated using STATA 12.0 software. Results The measurements obtained through all the three techniques showed high interclass correlation coefficients and excellent level of agreement. The failure rate of measurements obtained through conventional radiography, digital radiography and electronic apex locators was 38, 30 and 22% respectively. Combination of conventional radiography with electronic apex locator showed an accuracy of 90%, while combination of digital radiographs and electronic apex locators given an accuracy of 96%. Conclusion A combination of digital radiographic and apex locator methods for determining the root canal length in permanent teeth can be considered safe, reliable and precise.