A comparative assessment of the accuracy of electronic apex locator (Root ZX) in the presence of commonly used irrigating solutions

Comparative evaluation of working length determined using integrated apex locator and root ZX mini under various irrigating solutions: An in vivo study

Background

Electronic apex locators (EALs) are frequently used as adjuvant to radiographs in working length (WL) determination. The introduction of integrated apex locators (IALs) further simplified the root canal treatment by continuous monitoring of the apex while root canal shaping.

Aim

The aim of this study was to evaluate the efficacy of radiographs, EAL, and IAL in determining the WL in the presence of various irrigants.

Materials and Methods

The present in vivo study was carried out on 30 patients who were divided into 10 in each group, based on the type of irrigant used; 0.9% saline (Group 1), 0.2% chlorhexidine (Group 2), and 2.5% of sodium hypochlorite (NaOCL) (Group 3). In each group, WL is determined using conventional radiographs, Root ZX Mini (EAL), and CanalPro CL2i (IAL).

Statistical Analysis

Kruskal-Wallis test and Friedman's two-way ANOVA test were used for statistical analysis.

Results

Mean WL was comparably lower with Root ZX Mini, while the WL by CanalPro CL2i and the radiographic method were comparable. In all methods, the type of solutions used did not influence the WL, with a higher mean WL when NaOCL is used as an irrigant. Nevertheless, the above comparisons were not statistically significant.

Conclusion

the irrigation solutions employed in this study had no impact on the performance of apex locators and radiographs.

Effect of Sodium Hypochlorite Concentration on Electronic Apex Locator Reliability

This ex vivo study aimed to measure the performance of an electronic apex locator (EAL) in the presence of sodium hypochlorite irrigants with different concentrations. Two EALs (Root ZX Mini and Locapex 6) were used to locate the apical foramen in 10 extracted single-rooted teeth in the presence of 0.5%, 2.5% and 5% sodium hypochlorite. Visual working lengths were also determined using #10 K-file under a microscope before the electronic measurements were made. The performance of both EALs was compared for the electronic working lengths determined under the different concentrations of sodium hypochlorite. A multiple-way ANOVA and PLSD Fisher’s test with an α risk fixed at 5% were conducted. There were no statistical differences in the working lengths determined by both EALs between the three groups with different concentrations of sodium hypochlorite and their visual control measurements. When a ± 0.5 mm margin was applied, the Root ZX Mini and the Locapex 6 presented 88% and 83% accuracy, respectively. Sodium hypochlorite concentration in irrigants does not affect the accuracy and reliability of either the Root ZX Mini or the Locapex 6. Electronic apex locators are reliable with any concentration of sodium hypochlorite irrigants.

Apexoconnection: A Novel Technique to Determine Working Length

Purpose

The aim of this study was to evaluate and compare the accuracy of working length (WL) determination when using the conventional electronic WL (EWL) technique versus using the novel Apexoconnection technique involving EWL with a connector (EWLc).

Materials and Methods

Sixty extracted posterior teeth with a total of 118 root canals were selected for the study. The real WL (RWL) of each canal was verified using a dental microscope under 25.6x magnification. Root canal lengths were measured with an apex locator using the attachment device directly attached to the hand file in the root canal and then adding another hand file as a connector between the attachment device and the file in the root canal. The distance from the file’s stopper to its tip was measured using a digital caliper. Statistical analysis was carried out to analyze the data between experimental groups.

Results

The results of the statistical test showed that the differences in the WL determined by either technique and the proper length as determined under the microscope were not statistically significant. The results of the statistical test comparing the groups were also not statistically significant.

Conclusion

In this in vitro study, both the novel and conventional techniques were equally accurate for determining WL when compared with the RWL.

Comparative Evaluation of Accuracy of Two Electronic Apex Locators in the Presence of Contemporary Irrigants: An In vitro Study

Aim:

The present study was aimed to compare the accuracy of Root ZX Mini and Propex II in the presence of 0.1% octinidine dohydrochloride (OCT), 2% chlorhexidine gluconate (CHX), and 5% sodium hypochlorite (NaOCl) heated and nonheated before and after preparation.

Materials and Methods:

Eighty extracted single-rooted teeth were selected for the study and decoronated. Teeth were mounted in an alginate model. Actual working length (AL) was measured using a stereomicroscope under ×4 magnification. Electronic working length measurements were recorded using Root ZX Mini and Propex II apex locators in the presence of 0.1% OCT, 2% CHX, and 5% NaOCl (nonheated and heated to 60°C) before and after preparation. Mean and standard deviation differences before and after preparation were calculated and statistically analyzed using analysis of variance and paired t-test.

Results:

The accuracy of Root ZX Mini before and after preparation within ±0.5 mm of AL was consistently high in the presence of irrigants than Propex II. 5% NaOCl (heated and nonheated) showed more variation than the other irrigants, in the working length determination in both the apex locators.

Conclusion:

Electronic length measurements were shorter with heated and nonheated 5% NaOCl and longer with 0.1% OCT and 2% CHX for both the electronic apex locators.

Influence of Root Canal Curvature on the Accuracy of Root ZX Electronic Foramen Locator: An In Vitro Study

Introduction:

The aim of this in vitro study was to evaluate the correlation between accuracy of Root ZX electronic foramen locator and root canal curvature.

Methods and Materials:

One hundred and ten extracted mandibular molars were selected. Access cavity was prepared and coronal enlargement of mesiobuccal canal was performed. A #10 Flexofile was inserted into the mesiobuccal canal, and a radiography was taken to measure the degree of curvature by Schneider's method. The actual working length (AWL) was defined by inserting the file until its tip could be observed at a place tangential to the major apical foramen and then 0.5 mm was subtracted from this measurement. For the electronic working length (EWL) measurement, the apical 3 or 4 mm of the root was embedded in alginate as the electrolyte material. The file was inserted into the root canal to the major foramen, until the APEX reading was shown on the electronic device and then pulled back until the visual display showed the 0.5-mm mark. The AWL was subtracted from the EWL to define the distance between the file tip and the point 0.5 mm coronal to the major apical foramen. Data were analyzed using the Pearson’s correlation coefficient.

Results:

The accuracy of Root ZX within ±0.1 mm and ±0.5 mm was 38.2% and 94.6%, respectively. There was no correlation between the distance from the EWL to the AWL and the degree of root canal curvature (r=0.097, P=0.317).

Conclusion:

Root canal curvature did not influence the accuracy of Root ZX foramen locator.

Foramen Changes following Over Instrumentation of Curved Canals with Three Engine-Driven Instruments: An In Vitro Study

INTRODUCTION

The present in vitro study aimed to evaluate and compare the changes in shape and surface area of the major foramen following shaping of curved canals with three new generation NiTi engine-driven instruments naming ProTaper Next, BT RaCe and WaveOne Gold- with 3 different levels of protrusion beyond the major apical foramen.

METHODS AND MATERIALS

A total of 45 extracted human molars with at least one curved canal were distributed in 3 comparable groups of 15 that were instrumented using either ProTaper Next (PTN), BT RaCe (BTR) or WaveOne Gold (WOG). The canals were instrumented to the major foramen and then over instrumented with the final file 0.5 mm, 1 mm and 1.5 mm beyond the foramen. Standardized pre- and post-instrumentation photographs of the foramen were obtained for all groups using a stereomicroscope. Foramen shape and surface area were evaluated using the AmScope software for measurements and compared between groups and levels of instrumentation applying binary conditional logistic regression and repeated measures ANOVA. The level of significance was set at 0.05.

RESULTS

Foramen shape tended to gradually change from circular to oval as the level of instrumentation increased in all groups. The original foramen shape in WOG group remained better than other groups. Foramen surface areas increased in all groups with Group BTR demonstrating significantly greater values than the other 2 groups.

CONCLUSION

Over instrumentation resulted in apical enlargement and ovalization in all 3 groups but with different patterns. These differences can be attributed to the final file size, design characteristics and kinematics of the 3 systems.

The Effect of File Size and Type and Irrigation Solutions on the Accuracy of Electronic Apex Locators: An In Vitro Study on Canine Teeth

Measurements of the root canal during endodontic treatment have a significant influence on the course of the therapeutic process as well as on its final result in both human and veterinary medicine. The apical constriction should be the termination point for the preparation and filling of the root canal. This research was conducted with the use of a Septodont kit consisting of a small chamber filled with the examined solution in which a healthy second incisor was placed. The step back method was applied for the root canal preparation and master apical file of 30 was used. The working length was 22 mm. The examination was conducted with the use of steel as well as nickel titanium hand instruments. Different irrigation solutions and two types of apex locators were used. Measurements of the working length of the root canal showed dependence on the size of the instrument. Examinations carried out in various environments showed that analogical measurements were obtained only for sodium hypochlorite solutions. In other environments the measured sections were shortened. Comparative examinations with the use of steel instruments demonstrated insignificant measurement differences. Compared to these results, the measurements in nickel titanium group were characterized by more considerable deviations.