Objective: The aim of this study was to compare the influence of the pulp condition (vital or necrotic) on the determination of the root canal length by using a fourth generation electronic apex locator (EAL).
Study design: The Elements Diagnostic Unit and Apex Locator was used to measure 143 teeth, totaling 294 canals with different conditions (236 necrotic and 58 vital pulp), for root length. After assessing the root canal and ascertaining the tooth length by using the EAL, the position of the file was confirmed by radiograph. The distance between the file tip and the root end was measured radiographically and was compared with the electronic measurement.
Results: Under clinical conditions within an acceptable range lower than 0.5 mm, the concordance between the 2 measurements was 96.6%. This new EAL showed no significant difference (P < or = .05) on accuracy of root canal length determination between vital cases (94.8%) and necrotic cases (97%).
Conclusion: This device proved to be reliable regardless of the pulpal vitality.