Comparison of working length determination by NSK electronic apex locator with the radiographic method on necrotic deciduous molars: In vitro

Working length determination is a basic procedure in endodontic treatment of permanent and deciduous teeth. Radiography is the conventional method of canal length determination. In this method the distance between tip of the file inserted in the root canal and the tip of the radiographic apex is measured. The purpose of this study was to compare working length determination by NSK (NSK; Japan) electronic apex locator (EAL) with the radiographic method on necrotic deciduous molars. Subjects and

This in vivo study performed on 60 root canals of 20 primary molars. Canal length measured by NSK (NSK; Japan) electronic apex locator compared with radiographic method. Paired samples test was used for the statistical analysis.

The mean canal length of D teeth was 13. 82 mm with the radiologic method، and 13. 83 mm with EAL. There were no significant differences between the two methods (P= 0. 81). The average canal length of E teeth was 15. 03 mm with the radiologic method، and 15 mm with EAL showed no statistically significant differences between the two methods (P= 0. 57). Totally the canal length was 14. 43mm with the radiologic method، and 14. 42 mm with EAL with no statistical significant differences (P=0. 85).

According to these results of this study we can use EAL instead of radiographic method in working length determination of primary teeth.