Accuracy of Working Length Determination of Curved Canal Using Digital and Film-Based Radiography

Digital and film-based radiography are the most common methods of working length determination. The objective of this study was to compare the accuracy of working length determination of curved canals using digital and film-based radiography.

This experimental and interventional study, included forty teethwith curved canals conducted atthe Dentistry Faculty of Isfahan University of Medical Sciences, in 2018. After access cavity preparation, the direct observation method of the apical tip of the file in the root apex determined the actual working length. Teeth were mounted in acrylic blocks. Canal curvature was calculated based on Schneider’s method using software of indirect digital radiography. Images gathered by E-speed film and digital sensors. A pre-curved file was used to measure the working length offilm-based images. In digital radiography, a digital caliper was used to measure the working length with three and six clicks. Data were analyzed by repeated measure analysis, paired t-test, and Intraclass Correlation Coefficient. The Level of significance was set at 0.001.

All groups overestimated the actual length although there weren’t any significant differences (p value > 0.05). Paired t-test didn’t show any significant differences between digital and film-based groups (p value > 0.05).

Considering several advantages of digital radiography over the film-based method, it is the preferred method for working length determination of curved canals.