Comparative Evaluation of Working Length Using Conventional Radiographic Method, Radiovisiography, and Apex Locator in Single-rooted Permanent Teeth

Ab s t r Ac t Introduction: The success of any root canal treatment depends on the accurate determination of the working length, biomechanical preparation, and obturation. Radiographs (conventional and radiovisiographs) have remained the mainstay modality in the determination of working length, although they are associated with disadvantages of high radiation exposure and increased treatment time. Apex locators are relatively regularly used equipment in working length determination, but their accuracy has been questioned time and again. Aim and objective: The present study was done to evaluate and compare the accuracy of conventional radiographs, radiovisiographs (RVGs), and apex locators for the determination of working length. Materials and methods: The present in vitro study was carried on 60 extracted single-rooted permanent teeth, and the working length was determined using three methods viz. conventional radiography, RVG, and apex locators. The three methods used were intercompared, and in addition comparison with actual working length of the tooth was also made. Results: Among the three methods, the conventional radiographic method was found to be closest to the actual root canal length followed in order by RVG and electronic apex locator. Intercomparison between all three methods and actual root canal working length was found to be statistically significant except between conventional radiography and actual root canal working length. The difference between the mean values of root canal working length for conventional radiography and actual root canal working length was 0.01 mm, for RVG and actual root canal working length was 0.13 mm, and for electronic apex locator and actual root canal working length was 0.70 mm. Conclusion: All the three methods for the determination of working length used in the study are clinically acceptable and are associated with advantages and disadvantages. Further research and advances may make electronic apex locator the technique of choice in working length determination, or a combination of the RVG and apex locator may be the future in endodontic therapy.