BACKGROUND: This study aimed to investigate the perspectives, preferences, and clinical experiences regarding using electronic apex locator and apex locator integrated instrumentation of dentists and endodontists.
METHODS: A web-based questionnaire consisting of 3 parts and 23 closed-ended questions to achieve the objective of the study was carried out in ethical conditions between August and October 2023. The first part of survey included demographic information, while the second part was about evaluating electronic apex locator usage. In the last part, only participants\' use of apex locator-integrated instrumentation was evaluated. Data were analyzed at a significance level of p < 0.05.
RESULTS: A total of 297 clinicians, including 59 endodontists and 34 endodontic residents/Ph.D. students participated in the questionnaire. Endodontists and endodontic residents/Ph.D. students perform statistically significantly more root canal treatments per week on average (p = 0.001). For the working length determination method (multiple option question), 78.5% of participants use an electronic apex locator and 39.7% apex locator-integrated engines. However, the preference rate for electronic apex determination technique was generally 95.6%, with the full rate confirmation of endodontists and endodontic residents/Ph.D. students (100%). A total of 21 endodontists out of 59 prefer apex locator integrated engine-driven instrumentation. Although many of these specialized clinicians use this technique, they stated that they measure electronic working length passively for confirmation of the working length before (90.5%) and after the preparation (66.7%).
CONCLUSIONS: Dentists, as well as endodontists, are skeptical about apex locator-integrated engine-driven instrumentation. Using this technique as a supporter rather than a primary way for preparation within safe limits may give safer results in terms of treatment outcomes.

UNASSIGNED: An accurate working length (WL) estimation is fundamental to a successful endodontic therapy. The objective of this comparative in vitro research was to investigate the performance of iPex II and the Root ZX Mini electronic apex locators (EALs) in measuring root canal WL with different irrigant solutions and their relation to the electrical conductivity of irrigation solutions.
UNASSIGNED: Seventy sound permanent lower premolar teeth, each with a single root and developed apices, were used. Under an X15 stereomicroscope, the real working length was determined with the aid of a #10 file. After that, teeth were placed into an alginate model, and the iPex II and Root ZX Mini were used for the detection of electronic working length with various irrigants. Seventy teeth were randomly distributed into seven groups, 10 per each group (group I: dry canal; group II: distilled water; group III: ozonated water; group IV: 5% sodium hypochlorite (NaOCl); group V: 2% chlorhexidine, group VI: 17% ethylenediaminetetraacetic acid (EDTA) solution, and group VII: 17% EDTA gel). The difference in WL was calculated by deducting real working length from its electronic working length. The study also evaluates the electrical conductivity of the seven endodontic irrigant solutions. The two-way analysis of variance (ANOVA) test was used for statistical analysis.
UNASSIGNED: Statistically, neither both types of EALs (P = 0.088) nor various irrigating solutions with varying electrical conductivities (P = 0.099) significantly affect the accuracy of EL estimation.
UNASSIGNED: There were no significant differences between the accuracy of the Root ZX Mini and the iPex II. The accuracy of both apex locators is unaffected in the presence of various irrigation solutions with varying electrical conductivities in this research.

BACKGROUND: Endodontic treatment aims to eradicate both microbial infection and inflammatory processes within the root canal space as well as in the periapical (PA) region of the tooth. To achieve this, the canals should be cleaned, shaped, disinfected, and obturated to the proper working length. Clinically, the working length is described as the measurement from the coronal reference point to the physiological apex located at the apical foramen. In the available literature, electronic apex locators (EAL) with periapical (PA) radiographs are the most reliable and precise tools for determining the working length in routine root canal treatment. Therefore, the aim of this retrospective clinical study is to evaluate if cone beam computed tomography (CBCT) scans are reliable and accurate in measuring endodontic working length compared to standard clinical measurement methods.
METHODS: Patients who fit the inclusion criteria were identified. A postgraduate endodontic resident blinded to the cone beam computed tomography scan results treated all teeth in the field of view that needed endodontic treatment. The root canal length was determined using J Morita Root ZX II apex locator (J Morita Corp., Kyoto, Japan) and periapical radiographs. The dental radiology specialist interpreted the pre-existing cone beam computed tomography (CBCT) scan images and determined the working length. Statistical comparisons of the working length measurements of EAL and CBCT were performed using paired sample t-tests after verifying normality.
RESULTS: No statistically significant differences in the working lengths were found in all canals with the exception of the palatal canal only (t=2.16, p=0.034), suggesting consistent measurements between EAL and CBCT.
CONCLUSIONS: In teeth requiring endodontic treatment, pre-existing cone beam computed tomography scan images are accurate as electronic apex locators when determining the working length. A limitation of this study is that it only includes a limited number of samples and is affected by operator variation.

BACKGROUND: Successful endodontic treatment needs accurate determination of working length (WL). Electronic apex locators (EALs) were presented as an alternative to radiographic methods; and since then, they have evolved and gained popularity in the determination of WL. However, there is insufficient evidence on the post-operative pain, adequacy, and accuracy of EALs in determining WL.
OBJECTIVE: The systematic review and meta-analysis aims to gather evidence regarding the effectiveness of EALs for WL determination when compared to different imaging techniques along with postoperative pain associated with WL determination, the number of radiographs taken during the procedure, the time taken, and the adverse effects.
METHODS: For the review, clinical studies with cross-over and parallel-arm randomized controlled trials (RCTs) were searched in seven electronic databases, followed by cross-referencing of the selected studies and related research synthesis. Risk of bias (RoB) assessment was carried out with Cochrane\'s RoB tool and a random-effects model was used. The meta-analysis was performed with the RevMan software 5.4.1.
RESULTS: Eleven eligible RCTs were incorporated into the review and eight RCTs into the meta-analysis, of which five had high RoB and the remaining six had unclear RoB. Following meta-analysis, no significant difference in postoperative pain was found among the EAL and radiograph groups (SMD 0.00, CI .29 to .28, 354 participants; P value = 0.98). Radiograph group showed better WL accuracy (SMD 0.55, CI .11 to .99, 254 participants; P value = 0.02), while the EAL group had 10% better WL adequacy (RR 1.10, CI 1.03-1.18, 573 participants; P value = 0.006).
CONCLUSIONS: We found very low-certainty evidence to support the efficacy of different types of EAL compared to radiography for the outcomes tested. We were unable to reach any conclusions about the superiority of any type of EAL. Well-planned RCTs need to be conducted by standardizing the outcomes and outcome measurement methods.

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.

UNASSIGNED: Apex locators are important devices that can be used to determine working length during root canal treatment. However, it is not known whether electronic devices with various wave length frequencies influence the accuracy of apex locators. The aim of this study was to determine whether a cordless phone set, MP4 player, FM radio, asymmetric digital subscriber line (ADSL), or a mobile phone could influence the accuracy of working length determination by the Dentaport ZX apex locator.
UNASSIGNED: In this study, twenty-four sound intact single-rooted extracted human teeth were used. After determining the root canal length with a file and a microscope, the canals were measured with three separate Dentaport ZX apex locators while one of the test devices (ADSL, MP4, FM radio, mobile phone, and cordless phone) was used at a distance of 50 cm from the apex locator. Bland-Altman plots was used for reliability and consistency.
UNASSIGNED: Except for the FM radio, all other devices showed significant difference with actual working length (P<0.05). ADSL and MP4 player showed the least consistency compared to the other devices.
UNASSIGNED: Based on this in vitro study, the use of ADSL, MP4 player, mobile phone, and cordless phone during root canal treatment may influence working length determination with the Dentaport ZX apex locator.

UNASSIGNED: Electronic apex locators are among the most acceptable instruments for determining root canal length. The present study aimed to evaluate the effect of long service life on the accuracy of the Dentaport Root ZX (DP ZX) electronic apex locator (EAL).
UNASSIGNED: In this study, fifty single-rooted freshly extracted human teeth were used. After determining the root canal length with a K-file and a dental operative microscope, the canals were measured with four separate DP ZX apex locators (two with more than 6 years of life service while two others had less than 6 years of life service). Data were analyzed by repeated ANOVA measurement.
UNASSIGNED: No significant difference was found between the EALs with different years of life services (P=0.62). All EALs could determine root canal length with high accuracy of more than 94%.
UNASSIGNED: Based on the results of this in vitro study, the long service life had no significant impact on the accuracy of DP ZX EALs in terms of root canal length determination.

This study aimed to compare the accuracy of three types of apex locators versus digital radiography for working length (WL) determination. This experimental study was conducted on 58 extracted maxillary premolars. The teeth were decoronated, the access cavity was prepared, and WL was determined using a #15 K-file to serve as reference. The WL was then measured by Woodpex V, Woodpex III, and Root ZX apex locators in the presence of 0.9% saline, and also on a photostimulable phosphor plate (PSP) digital radiograph taken by the parallel technique. The values were compared with the actual WL using the paired t-test (alpha = 0.05). Digital radiography, Root ZX, Woodpex V, and Woodpex III determined the WL within ±0.5 mm from the actual value in 84.48%, 100%, 89.66%, and 87.93% of the cases, respectively. Woodpex V (p = 0.039), Woodpex III (p = 0.001), and Root ZX (p = 0.001) significantly over-estimated the WL. The WL measured on digital radiographs was not significantly different from the actual WL (p = 0.213). The position of the apical foramen (central/lateral) had no significant effect on the accuracy of WL determination by different techniques (p >0.05). Within the limitations of this in vitro study, all the tested modalities showed acceptable accuracy for WL determination in maxillary premolars.

We evaluated in vitro the influence of nickel-titanium instruments kinematics on the accuracy and variation of root canal working length measurements, performed with an integrated apex locator, at glide path and at the end of shaping. Forty-four mandibular incisors, included in an alginate model, were allocated at random to two groups: reciprocating and rotary. Working length was determined at glide path stage and at the end of shaping. Measurements given by the integrated apex locator were matched with visual measurements. The apex locator accuracy was based on inter-group comparison. The variation in working length was based on intra-group comparison. Kinematics influenced the accuracy of measurements only after shaping (p < 0.05), and not in the glide path (p > 0.05). Rotary had values closer to the visual measurements. Diminishing of measures occurred after shaping for reciprocating (p < 0.05); and at glide-path stage for rotary (p > 0.05). The integrated apex locator was more accurate with rotary kinematics.

This study aims to evaluate the ability of Raypex 6, Propex Pixi, Dentaport ZX, Apex ID, Propex II and Dr.\'s Finder NEO to detect minimum root canal perforation diameter. One hundred single-rooted, extracted human teeth were artificially perforated by 5 burs in different diameters (0.25-1.25 mm) in 5 mm above the apex. Twenty teeth were assigned to each group. The actual canal lengths (AL) were measured under stereomicroscope followed by a measurement of electronic canal length (EL) using each electronic apex locator (EAL). None of the EALs were able to detect the perforation at diameters of 0.50 and 0.25 mm. Although all EALs used in our study were unable to detect perforations at diameters of 0.5 mm and 0.25 mm, they were highly successful in the determination of simulated root perforations at diameters of 1.25, 1 and 0.75 mm.