Accuracy of Working Length Determination - Electronic Apex Locator Versus Cone Beam Computed Tomography


  • Sunayna Kumari
  • Sharjeel Memon
  • Bilal Arjumand
  • Amna Yusuf Siddiqui
  • Jazib Memon
  • Osama Shujaa Alothmani
  • Rakhi Issrani
  • Muhmmad Rizwan Memon
  • Azhar Iqbal
  • Osama Khattak
  • Namdeo Prabhu


Electronics, Endodontics, Mandible, Maxilla


Objective: To compare the accuracy of working length determination between cone beam computed tomography (CBCT) and electronic apex locator by measuring the actual working length of teeth. Material and Methods: A total of 150 single-rooted tooth assessed by radiograph undergoing root canal therapy were selected. The process was repeated to obtain a buccolingual and mesiodistal section of all teeth. The measurement line was considered from the reference occlusal plane following the center of the canal to the terminus. All information regarding the accuracy of cone-beam computed tomography and apex locator was noted in a pre-designed proforma. Results: CBCT consistently demonstrated high accuracy across all tooth types in both jaws. The electronic apex locator exhibited varying precision, with greater accuracy observed in the mandible. Statistical analyses revealed significant differences in electronic apex locator accuracy among tooth types in the maxilla (p=0.042), emphasizing the importance of specific clinical considerations. Conclusion: Cone beam computed tomography emerges as a reliable diagnostic tool for accurate working length determination, especially in complex cases, while the electronic apex locator remains valuable with careful consideration of potential variations in accuracy. An individualized approach, considering tooth type, jaw location, and clinical context, is crucial for precise working length determination in endodontic practice.


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How to Cite

Kumari, S., Memon, S., Arjumand, B., Siddiqui, A. Y., Memon, J., Alothmani, O. S., Issrani, R., Memon, M. R., Iqbal, A., Khattak, O., & Prabhu, N. (2024). Accuracy of Working Length Determination - Electronic Apex Locator Versus Cone Beam Computed Tomography. Pesquisa Brasileira Em Odontopediatria E Clínica Integrada, 24, e230241. Retrieved from



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