Clinical Comparison of the accuracy of root canal length determination in permanent teeth by means of Root ZX electronic apex locator, tactile perception and conventional radiography

Document Type : Original Article


1 Department of Endodontics, Faculty of Dentistry, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.

2 Department of Oral and Maxillofacial Radiology, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.

3 Dentist.

4 Department of periodontics, Faculty of Dentistry, Tehran Islamic Azad University,Tehran, Iran

5 Department of Peadiatrics, Faculty of Dentistry, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.


Background and Objectives: Today, several methods have been proposed to determine the root canal length.The purpose of this clinical study was to compare the accuracy of root canal length determination in permanent teeth with ROOT ZX electronic apex locator, tactile perception and conventional radiography. 
Subjects and Methods: Sixty four canals from twenty  molar teeth  from healthy volunteers selected. Access cavities were prepared and working length were determined by means of tactile perception, Root ZX electronic apex locator and conventional radiography and compared with real working length. Data were analyzed via Paired samples T-test.
Results: The accuracy of determination of root canal length by Root ZX, radiography and tactile perception were 93.7, 76.57 and 50% respectively. T test analysis revealed no significant difference between working length determination by Root ZX and real working length (p=0.193). However, there were significant differences between working length determination by   radiographic length and tactile perception with real working length (P<0.001).
Conclusion: The Root ZX apex locator is useful in detecting the root canal length of permanent teeth with radiographic method. However,tactile perception  is not reliable in detecting root canal length


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