Accuracy of the Raypex-4 and Propex apex locators in detecting horizontal and vertical root fractures: an in vitro study.

Unforeseen root fractures during endodontic therapy are often difficult to diagnose and treat. Apex locators have been shown to be accurate in measuring the working lengths of root canals, and it was postulated whether they could also be used to determine the position of root fractures. This study was undertaken to assess the accuracy of two different apex locators in determining the position of fractures. One hundred single rooted teeth were randomly divided into two groups. One group had simulated horizontal fractures cut into them and the other group had vertical fractures. All fractures were detected in both groups using both a Propex (third generation) and a Raypex-4 (fourth generation) apex locator. The actual lengths of the fractures were then measured under 2.5 times magnification, and the results subjected to statistical analysis. Both locators produced similar results and were found to be very accurate, with measurements that correlated closely to the actual lengths. Clinically, treatment options for root fractures vary depending on their location. Thus apex locators may be a valuable aid in not only determining the presence of a root fracture, but also its exact location, which will help the clinician decide on the most appropriate management.