Journal of AdvancedMedical and Dental Sciences Research

Background: The success of root canal treatment depends on the removal of infected pulp tissue, necrotic material, and microorganisms from the root canal and achieves homogeneous filling of the entire canal. Therefore, determining an accurate working length (AWL) is one of the most important steps of endodontic therapy. Material and method: 40 single rooted completely formed freshly extracted teeth were used for this study. After administering local anesthesia access was opened and no 15 file was used to determine the working length with apex locators. The sequence of use of Raypex 5 and Root ZX was kept at random to remove bias. The file was sealed at this position using permanent dental cement and the excess coronal portion was cut off using an orthodontic cutter. This was followed by atraumatic tooth extraction and immersing in hypochlorite solution to remove organic debris. Apical 5 mm of the root apex was then shaved off with a bur under a microscope. The last layers were removed by a BP blade. This was followed by measuring the distance of the end of the file to the minor diameter under stereomicroscope at ×10. Results: The mean distance between the instrument tip and the minor diameter was +.0001± 0.2054 mm for the Root ZX and +0.042 ± 0.229 mm for the Raypex 5. The minor diameter was coinciding with the tip of the instrument in 9 cases when Root ZX was used and in 10 cases when Raypex was used. In 92.5% of cases tested with Root ZX the minor diameter was within the limit of ±0.5 mm. In 95% of cases, minor diameter was within a limit of ±0.5 mm with Raypex 5. No significant difference was seen between the results of Root ZX and Raypex 5 in determining the minor diameter. Conclusion: Root ZX and Raypex 5 were almost equally effective in determining the minor diameter of teeth. Key words: Minor diameter, Raypex 5, Root ZX