In Vitro Evaluation of the Accuracy of Three Electronic Apex Locators Using Different Sodium Hypochlorite Concentrations

Abstract

Background and Objectives: The aim of this study was to compare the accuracy of three types of electronic apex locators (EALs) when two different concentrations of NaOCl irrigation solutions are used by two operators. Materials and Methods: After creating the access cavities for 20 single rooted extracted teeth, the actual canal length (ACL) of each canal was determined visually using a #10 file and magnification. The teeth were subsequently inserted in plastic molds filled with alginate. The electronic measurement of root canal length (EWL) was performed using three different electronic apex locators: Root ZX II, Apex ID, and Dual Pex. Two independent operators, an endodontic specialist with 20 years practice and an undergraduate student in the final year of study, performed the irrigation procedures with two different concentrations of NaOCl (2% and 5.25%), and then measured the EWL using each of the EALs. The accuracy of all EALs, was determined in each case by subtracting the EWL from the ACL. Statistical analyses were performed using one-way ANOVA test. Results: In the presence of 2% NaOCl solution, for a margin error of ±0.5 mm, Root ZX II, Apex ID, and Dual Pex presented an accuracy of 90%, 80%, and 85% respectively. The increase in the concentration of the irrigation solution affected the accuracy of Root ZX II and Apex ID for both operators, diminishing it to 75% for the same margin error, but improved Dual Pex’s accuracy to 100%. Conclusions: The best accuracy in working length determination was obtained by Root ZX II for 2% NaOCl solution and by Dual Pex for 5.25% NaOCl solution with no significant statistical difference when compared.

Evaluation of accuracy of an electronic apex locator in presence of sodium hypochlorite in primary teeth with and without resorption

“…Studies evaluating the accuracy of EALs in the presence of root canal irrigation solutions in permanent molars have produced varying findings. Some studies have determined that irrigation solutions do not affect the accuracy of EALs [22,23], while others have reported that irrigation solutions may cause short or long measurements [20,25]. This is the first study to evaluate the accuracy of an EAL in resorption primary teeth in the presence of NaOCl.…”

“…It has been reported in some studies that modern EALs can maintain their accuracy in the presence of irrigation solutions [22,23]. Some authors argue that the presence of electrolyte solutions in the root canal is one of the most important factors affecting measurements made using EALs.…”

Accuracy of Root ZX Electronic Apex Locator in Relation to Two Different Employment Protocols: An In Vitro Study

“…The use of double stoppers was intended to reduce potential errors from movement while measuring file length [8,9,17]. All measurements were taken twice [9,22,23]. Following this protocol, a total of 450 readings were obtained: 150 recordings to determine the actual length and 300 measurements acquired by the Root ZX.…”

“…We used the Root ZX with K-file size 8 since this size provided significantly higher accuracy compared to size 15 [9]. The use of 5% NaOCl should not have affected our results since the accuracy of Root ZX was not affected by the different concentrations of NaOCl [22,24]. Overall, rigorous efforts were implemented to standardize and control potential factors that could impact the results of the current study.…”