MIGUITA, Kenner Bruno et al. Comparative analysis of two electronic apex locators in working length determination at endodontic therapy: an in vitro study. RSBO (Online) []. 2011, 8, 1, pp. 27-32. ISSN 1984-5685.

INTRODUCTION: Endodontic treatment comprises individual steps that should be effectively performed in order to achieve therapeutic success. Among these steps is the determination of the real tooth length, which prevents damage to the periapical tissues during instrumentation and obturation, due to restrict the operator action, favoring tissue repair. OBJECTIVE: The present study aimed to evaluate in vitro the reliability of two electronic apical locators (Root ZX II^® and Propex II^®) in working length determination, compared to direct visual measurement. MATERIAL AND METHODS: Forty single-rooted human teeth were selected; the pulp chamber was accessed and a size 10 Kerr file was inserted into the canal until its tip was visible at the apical foramen with x8 magnification. At this point, a rubber stop was placed on the file, at the incisal edge, and this length was measured with an endodontic ruler, therefore, recording the real tooth length (RTL). Then, the teeth were embedded in a vegetable sponge (loofah) base, soaked in saline solution. Electronic measurements were carried out using Root ZX II^® and Propex II^® locators, until an "Apex" reading was observed. The measurements obtained by the different methods were compared. RESULTS: Root ZX II^® apical locator showed 93% of correct readings, while Propex II^® locator was correct in 90% of the measurements. No statistically significant difference was observed between the two apex locators tested (p = 0.05). CONCLUSION: Both apex locators showed an acceptable percentage of correct readings and, therefore, may be recommended for clinical use.

: Endodontics; apical locator; working length.