Mini Apex Locator Research Articles

Comparative Assessment of Working Length Determination: Apex Locators versus Endomotor with Built-in Apex Locator in Single-Rooted Permanent Teeth.

To compare the effectiveness of Apex Locators and Endomotor with built-in Apex Locators for determining the working length in root canal treatment. A total of 120 patients were randomly assigned to three groups: Group 1 (Root ZX Mini Apex Locator), Group 2 (Minipex Apex Locator), and Group 3 (Endopilot Endomotor with built-in Apex Locator). Working length was determined using respective devices, followed by canal preparation and radiographic confirmation with a master cone. There was no statistically significant difference in working length determination between Apex Locators and Endomotor with built-in Apex Locators. Acceptable working length was achieved in 105 out of 120 cases. The Root ZX Mini, Minipex, and Endopilot demonstrated comparable efficacy in determining working length during root canal treatment. These devices offer reliable alternatives to traditional radiographic methods, providing clinicians with accurate measurements and contributing to successful treatment outcomes.

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

This study compared the accuracy of Root ZX mini apex locator in presence of sodium hypochlorite (NaOCl) in primary molars with and without apical resorption. Sixty-four extracted primary lower molar teeth with 32 root resorption and 32 without resorption were selected. To determine the actual working length (AWL), a K-file was inserted into the root canal until the tip of the file was visible at the major foramen or the resolution level. It was then withdrawn 1 mm. This value was recorded as AWL. The teeth were then divided subgroups (with/without NaOCl). To determine the electronic working length, a Root ZX mini apex locator in canals with/without NaOCl was used. A K-file was inserted into the canal to just beyond the foramen, as indicated by the flashing "APEX" bar, and the electronic working length was determined by subtracting 1 mm from this length. The deviation of the Root ZX mini measurement from the AWL was determined. Student's t-test was used for statistical analysis. In teeth with no resorption, the measurement accuracy rates (within+/-0.5 mm) of non-NaOCl and NaOCl groups were 84.37% and 81.25%, respectively (p > 0.05); within+/-1 mm, the non-NaOCl and NaOCl demonstrated 100% and 96.87% accuracy, respectively (p > 0.05). In teeth with resorption, the measurement accuracy rates (within+/-0.5 mm) was 81.25% for the non-NaOCl and 62.50% for the NaOCl, respectively (p < 0.05). The measurement accuracy rates (within+/-1 mm) of the non-NaOCl and NaOCl was 96.87% and 84.37%, respectively (p < 0.05). The presence of NaOCl in the root canal affected the accuracy of the Root ZX mini in primary teeth with apical resorption, but not in teeth without resorption.

Comparison of Radiovisiography, an Apex Locator and an Integrated Endomotor-inbuilt Apex Locator in Primary Teeth Endometrics.

Aim and objectiveTo compare the accuracy of radiovisiography (RVG), Root ZX mini Apex locator, and Endo radar's inbuilt Apex Locator during working length determination determination in primary teeth with the actual/direct canal length.Materials and methods58 primary teeth indicated for extraction in children of age group 4-12 years were selected. RVG, Root ZX mini Apex Locator, and Endo radar's Apex Locator were used to determine the working length intraorally. Following extraction of the teeth, the actual working length was determined with magnifying loupes (2.5×) using a K-file and an endodontic ruler. The data was tabulated and statistically analyzed.Results84 canals (58 teeth) were evaluated and Root ZX mini Electronic Apex Locator (EAL) showed no statistically significant difference with the actual measurement (p = 0.18) whereas Endo radar and RVG showed statistically significant difference. Endo radar underestimated, while RVG overestimated the working length. The most accurate method for working length measurements of the root canals in primary teeth was Root ZX mini EAL, followed by Endo radar and the least accurate was RVG.ConclusionThe Root ZX mini Apex Locator showed the most promising results and had an excellent degree of agreement with actual working length, followed by Endo radar and RVG.How to cite this articleKhan SA, Khanna R, Navit S, et al. Comparison of Radiovisiography, an Apex Locator and an Integrated Endomotor-inbuilt Apex Locator in Primary Teeth Endometrics. Int J Clin Pediatr Dent. 2022;15(S-1):S18-S21.

Evaluation of the effect of irrigants on the accuracy and repeatability of three electronic apex locators: an ex vivo study

Objective: To evaluate the effect of 2% chlorhexidine (CHX) and 2.5% sodium hypochlorite (NaOCl) on the accuracy and repeatability of three Electronic Apex Locators (EALs). Methodology: Thirty one human teeth were connected to a platform, irrigated with 2.0% CHX, and obtained two readings, again irrigated with 2.5% NaOCl and obtained two more readings. The distance between the tip of the file and the apical constriction was measured. Repeatability was calculated using the intraclass correlation coefficient (ICC) and repeatability coefficient (CR). Results: For CHX 2%, with the Mini Apex Locator, 25 of 31 electronic measurements were accurate (80.6%), 28 of 31 measurements for iPex (90.3%) and for Root ZX II 26 (83, 9%). For 2.5% NaOCl, with the Mini Apex Locator, 25 of the 31 measurements were accurate (80.6%), 28 of the 31 measurements for the iPex (90.3%) and for the Root ZX II, 24 (77, 4%). There were no differences between the two irrigants (p&gt;0.05). The values ​​(ICC) were 0.975 and 0.994 for the Mini Apex Locator, 0.981 and 0.971 for the i Pex and 0.994 and 0.995 for the Root ZX II. When using CHX, the (CR) was 0.196 for the Mini Apex Locator, 0.152 for the iPex and 0.088 for the Root ZX II. When using 2.5% NaOCl, the (CR) was 0.088 for the Mini Apex Locator, 0.196 for the iPex and 0.088 for the Root ZX II. Conclusions: The use of 2% CHX and 2.5% NaOCl did not affect the accuracy and repeatability of the three devices.

Comparative evaluation of root ZX Mini® apex locator and radiovisiography in determining the working length of primary molars: An In Vivo study

IntroductionWorking length determination is a crucial step for success of pulpectomy. Various new modalities have been developed. The newest technology includes EAL. Electronic apex locators require less chair side time, do not produce pain and avoid unnecessary radiation which makes it more superior in paediatric endodontic procedures. AimTo evaluate and compare Root ZX mini apex locator and Radiovisiography (RVG) for determining working length in primary molars. Materials and methodsA sample of 30 primary molar teeth was subjected to working length determination by Root ZX mini and RVG. The data was collected and then tabulated and subjected to statistical analysis. ResultsOn comparison among two groups, it was found there was no difference between the efficiency of modalities. A positive correlation was seen among Root ZX mini and RVG (ICC ​= ​0.99). ConclusionRoot ZX mini and radiovisiography are seen to be precise in determination of working length in primary molars. It can be said that Root ZX mini i. e the electronic apex locators can be used as an adjunct to Radiovisiography and conventional radiography.

Distance From File Tip to Apical Constriction/Apical Foramen in Relation To Numeric Scale Reading on Display of Two Electronic Root Canal Length Determining Devices

Modern Electronic root canal length determining devices (ERCLD) or Electronic apex locators (EALs), claim to determine accurately the tooth length based on the principle of measuring the impedance between the canal fluid and tip of the file with various frequencies. Many manufacturers claim the electronic apex locators (EALs) to exactly display the reading corresponding to the canal parameters. This invitro evaluation compared if the marks ‘‘0.5’’ and ‘‘0.0/APEX’’ on the of display of two EALs Sybron endo Apex ID (SID) and Mini apex locator (MINI) were accurately representing the apical constriction or the apical foramen respectively. Materials and Methods: Sixty extracted, single rooted human teeth were used with alginate model. The electronic length was determined using 2 EALs, at the numeric scale/target ‘‘0.5’’ and ‘‘0.0/APEX’’ mark using K-file (electrode). After cementing the file coronally with type II glass ionomer cement, the apical 3–4 mm was trimmed until the file tip was visible under an operating microscope (X16). Images were captured under Dental operating microscope and the error between electronic length (EL) and actual length (AL) at target interval 0.5 (apical constriction) and 0.0 (major foramen) were analyzed by used Image J software. RESULTS: t-test revealed statistically significant differences between EL determination and AL for both EALs, at “0.0”/Apex, p=0.001, and at 0.5 (apical constriction) p=0.007. CONCLUSION: The numeric meter display of newer generation EALs like Apex ID, represent better correlation with the histologic landmarks and could become a useful guide for inexperienced clinicians, however they do not always indicate the position of the file in the canal.

Evaluating Electromagnetic Interference of Communication Devices with Root ZX Mini Apex Locator

Introduction: The correct determination of working length is a critical factor in the success of endodontic treatment. Nowadays, the electronic apex locators (EALs) is more used because of their ease of use, high accuracy, and the uncertainty of other methods. Because EALs use the electronic method, it is likely that electromagnetic waves (EMWs) affect their performance. This study aims to investigate the possibility of this interference. Materials and Methods: The visual canal length (CL) of 12 maxillary incisors (Vertucci’s type I) was measured with a K-file and magnifying glass. Root ZX mini apex locator is used to measure CL in the absence/presence of EMWs in both the second (2G) and third generations (3G) of mobile communication network at the mode of ringing and conversation at direct contact and the distances of 25 and 50 cm. Results: The mean CL at presence of EMWs in all conditions and distances (by removing the conversation with 2G at direct contact group) were not significantly difference with CL and EAL and absence of investigated EMWs group (Repeated-Measures Analysis of Variance (ANOVA), P = 0.083). The indicator of EAL were unstable on apex sign at least 5 seconds for 5 teeth (41.7% of samples) in conversation with 2G at the direct contact group. Conclusion: EMWs of 2G and 3G not causes malfunctions of the Root ZX mini apex locator except conversation with 2G at the direct contact.

An in vitro evaluation of the accuracy of four electronic apex locators using stainless-steel and nickel-titanium hand files.

ObjectivesThe purpose of this in vitro study was to evaluate the accuracy of working length (WL) determination of four electronic apex locators (EALs), namely, Root ZX (RZX), Elements diagnostic unit and apex locator (ELE), SybronEndo Mini Apex locator (MINI) and Propex pixi (PIXI) using Stainless steel (SS) and nickel-titanium (NiTi) hand files. The null hypothesis was that there was no difference between canal length determination by SS and NiTi files of 4 EALs.Materials and MethodsSixty extracted, single rooted human teeth were decoronated and the canal orifice flared. The actual length (AL) was assessed visually, and the teeth were embedded in an alginate model. The electronic length (EL) measurements were recorded with all four EALs using SS and NiTi files at '0.5' reading on display. The differences between the AL and EL were compared.ResultsThe results obtained with each EAL with SS and NiTi files were compared with AL. A paired sample t test showed that there was a statistical significant difference between EAL readings with SS and NiTi files for RZX and MINI (p < 0.05). The accuracy of RZX, ELE, MINI and PIXI within ± 0.5 mm of AL with SS/NiTi files were 93.3%/70%, 90%/91.7%, 95%/68.3%, and 83.3%/83.3%, respectively.ConclusionsThe results of this study indicate that Root ZX was statistically more accurate with NiTi files compared to SS files, while MINI was statistically more accurate with SS files compared to NiTi files. ELE and PIXI were not affected by the alloy type of the file used to determine WL.

Interference of apex locator, pulp tester and diathermy on pacemaker function.

Aim:The purpose of this study was to evaluate the effects of three electronic apex locators (EAL), electric pulp tester (EPT) and diathermy on pacemaker function in vitro.Materials and Methods:Three EALs: Root ZX (J. Morita Co., Tustin, CA, U.S.A.), Propex (Dentsply), Mini Apex locator (SybronEndo, Anaheim, CA, USA), EPT (Parkell pulp vitality tester Farmingdale, NY, USA) and Diathermy (Neomed 250 B) were tested for any interference with one pacemaker (A medtronic kappa KVDD901-serial number: PLE734632S). Directly connecting the pacemaker lead with the EAL/EPT/diathermy operating on a flat bench top, the telemetry wand was held directly over the pacemaker to monitor the pacing pattern for a period of 30 s. Pacemaker activity was continuously recorded on the telemetric programmer and electro gram (EGM) readings examined for pacer inhibition, noise reversion or inappropriate pacemaker pulses.Results:All the three apex locators showed no pacing interference or background noise during its function or at rest. The EGM readings of EPT showed varying levels of background noise in between pacing however, this did not affect the normal pacing pattern and the pacing interval remained constant. EGM readings of diathermy showed an increase in the pacing interval (irregular pacing pattern) followed by complete inhibition of the pacing system.Conclusion:The tested EALs do not interfere with cardiac pacemaker function. The tested EPT showed varying levels of background noise but does not interfere with cardiac pacemaker function. Use of Diathermy interfered with the normal pacing, leading to complete inhibition of the pacing system.

Comparison of accuracy of Root ZX II and Root ZX Mini in presence of various irrigants: an in vitro study

Aim: Comparison of the effect of QMix, 7% maleic acid and 2.5% sodium hypochlorite on the accuracy of Root ZX II and Root ZX Mini apex locator. Methodology: 45 single rooted teeth were decoronated. Patency was checked and coronal flaring was done. They were then divided into 3 groups: i) QMix, ii) 7% Maleic acid and iii) 2.5% Sodium hypochlorite. The actual length of each tooth was determined before embedding them in an alginate model. 5ml of the respective irrigant was introduced into the canal. Working length was measured with Root ZX and Root ZX Mini apex locators. For each sample, an average of a total of three readings was considered. Statistical analysis was performed using Anova, Two Way, Post hoc, Paired t-tests. Results: Group I (QMix) showed no statistically significant results. Group II (7% Maleic acid), showed statistically significant difference from the actual length with Root ZX Mini (p=0.002). Group III (2.5% sodium hypochlorite) showed statistically significant difference from the actual length with Root ZX II (p=0.04) and Root ZX Mini (p=0.0002). A statistically significant difference was seen in the readings by both the apex locators (p=0.005). Conclusion: QMix does not affect the accuracy of apex locators. Root ZX II is more accurate than Root ZX Mini in the presence of 7% maleic acid and 2.5% sodium hypochlorite.

Accuracy and Repeatability of 3 Apex Locators in Locating Root Canal Perforations: An Ex Vivo Study

IntroductionThis study was an ex vivo evaluation of the accuracy and repeatability of 3 electronic apex locators (EALs) in locating simulated root canal perforations. MethodsThirty-five human teeth were used. Perforations were placed 5 mm from the apex of each specimen. A #15 K-file was attached to a micrometer, and the specimens were fixed in a mounting model. The EALs were connected to the files, and electronic measurements of the simulated perforations were obtained. This procedure was repeated, the files were cemented in place, and x-rays were obtained to evaluate the distances between the measurement files and the simulated perforations. The obtained results were compared with the corresponding control lengths. Three investigators evaluated the distance of the file position in relation to the perforation for each specimen. The 3 investigators reached consensus regarding these measurements. ResultsStatistical analyses of the results revealed that the EAL reliabilities in the exact detections of the root canal perforations were 97.1% for the Mini Apex Locator, 100% for the Root SW, and 91.4% for the Root ZX II. Analysis of variance revealed that the accuracies of the 3 devices were not different (P > .05). The results also indicated high levels of repeatability for each of the 3 EALs (intraclass correlation coefficients: 0998, 0.999, and 0.999 for the Mini Apex Locator, Root SW, and Root ZX II, respectively). ConclusionsIt was concluded that each of these 3 EALs provided excellent ex vivo accuracy in locating root perforations and that all tested devices possess excellent ex vivo repeatability.

Accuracy of five electronic foramen locators with different operating systems: an ex vivo study

Objective:The aim of this study was to evaluate, ex vivo, the precision of five electronic root canal length measurement devices (ERCLMDs) with different operating systems: the Root ZX, Mini Apex Locator, Propex II, iPex, and RomiApex A-15, and the possible influence of the positioning of the instrument tips short of the apical foramen.Material and Methods:Forty-two mandibular bicuspids had their real canal lengths (RL) previously determined. Electronic measurements were performed 1.0 mm short of the apical foramen (-1.0), followed by measurements at the apical foramen (0.0). The data resulting from the comparison of the ERCLMD measurements and the RL were evaluated by the Wilcoxon and Friedman tests at a significance level of 5%.Results:Considering the measurements performed at 0.0 and -1.0, the precision rates for the ERCLMDs were: 73.5% and 47.1% (Root ZX), 73.5% and 55.9% (Mini Apex Locator), 67.6% and 41.1% (Propex II), 61.7% and 44.1% (iPex), and 79.4% and 44.1% (RomiApex A-15), respectively, considering ±0.5 mm of tolerance. Regarding the mean discrepancies, no differences were observed at 0.0; however, in the measurements at -1.0, the iPex, a multi-frequency ERCLMD, had significantly more discrepant readings short of the apical foramen than the other devices, except for the Propex II, which had intermediate results. When the ERCLMDs measurements at -1.0 were compared with those at 0.0, the Propex II, iPex and RomiApex A-15 presented significantly higher discrepancies in their readings.Conclusions:Under the conditions of the present study, all the ERCLMDs provided acceptable measurements at the 0.0 position. However, at the -1.0 position, the ERCLMDs had a lower precision, with statistically significant differences for the Propex II, iPex, and RomiApex A-15.

The effects of six electronic apex locators on pacemaker function: an in vitro study

To assess the effects of six electronic apex locators (EALs) on pacemaker function in vitro. Six EALs (Mini Apex Locator®, Dentaport ZX®, Novapex®, Raypex5®, Root ZX mini®, and Justy II®) were tested for electromagnetic interference (EMI) with one pacemaker (Saint Jude Medical). The pacemaker, with a single electrode, was immersed in a saline solution bath adjusted to 400-800 hms to simulate the electrical resistance of the human body and to register the activity by the system. The pacemaker was tested with each of the EALs to analyse the presence of EMI with the EAL switched on, the EAL switched off and during EAL operation. Each series of tests began with a 15-second baseline recording (R0) and continued until all the recording conditions had been covered. The conditions were as follows: R1: recording with the lead of the EAL <2 cm from the tip of the electrode; R2: recording with the lead of the EAL <2 cm from the generator; R3: recording with the lead of the EAL <2 cm from the sensing arc; and R4: recording with the lead of the EAL 15 cm from the sensing arc. If any of the EALs produced interference, its characteristics were categorized. When the lead of the EAL was <2 cm from the tip of the electrode, the majority of the EALs tested produced only background noise. Only one (the Mini Apex Locator) resulted in EMI that was detected as false heart activity. When the EAL was <2 cm from the generator, just one EAL detected background noise (the Mini Apex Locator). When the EAL was <2 cm from the sensing arc or 15 cm from the sensing arc, the recordings were not affected by any of the EALs. There were no significant differences amongst the EALs analysed with respect to the production of EMI. EMI occurred when the EALs were placed close to the tip of the electrode and occasionally when close to the pacemaker; however, no EMI was detected when the EALs were placed near to or 15 cm from the sensing arc in this laboratory experimental model.

The Evaluation of Three Electronic Apex Locators in Teeth with Simulated Horizontal Oblique Root Fractures

ABSTRACT Aim The accuracy of three electronic apex locators (EALs) to locate the apical limit in teeth with simulated horizontal oblique root fractures was investigated. Material and Methods A horizontal oblique incomplete root fracture was simulated on 30 freshly extracted maxillary anterior teeth by means of a notch made on the vestibular root plane 8 mm from the anatomic apex. The EALs investigated were the ProPex II (Dentsply Maillefer, Ballaigues, Switzerland), the Mini Apex Locator (Sybron Endo, Orange CA), and the Dentaport ZX (J. Morita Corp, Kyoto, Japan). The electronic measurements were compared with the real “working length.” Results The accuracy obtained was Dentaport ZX in 66.66% (n=20), the Mini Apex Locator in 63.33% (n=4) and the Propex II in 53.34% (n=4). The analysis of variance and chi-square test showed no statistical significant differences between Propex and Dentaport ZX EALs (Elecronic Apex Locators) at 0.5 mm and 1.0 mm tolerance levels. These results suggest that electronic apex locators can effectively and reproducibly detect oblique root fractures. Conclusion Although Propex II apex locator was not able to determine the working length accurately, but Dentaport ZX and Mini Apex Locator were able to determine the working length within acceptable range.

Evaluation of two compact electronic apex locators in the presence of different endodontic solutions

The purpose of this study was to evaluate the accuracy of two compact electronic apex locators, the Root ZX mini and the Mini Apex Locator, in the presence of different endodontic solutions and to compare their performance to the Root ZX electronic apex locator. The sample consisted of 60 extracted single-rooted human teeth. Manufacturers’ recommendations were followed to operate each electronic apex locator to determine electronic length in the presence of 5.25% Sodium Hypochlorite, 2.625% Sodium Hypochlorite, 1.0% Sodium Hypochlorite, 0.9% NaCl, 2% lidocaine with 1:80,000 Epinephrine, and 2% Chlorhexidine. The difference between the electronic (EL) and actual length (AL) was calculated. In addition, EL measurements were classified into three categories: “correct” (AL±0.5mm), “long” (>0.5mm from AL), “short” (<−0.5mm from AL). There were no statistically significant differences in the accuracy of each of the three apex locators in the presence of the six endodontic solutions used in this study. The Root ZX mini and the Mini Apex Locator had similar accuracy to the Root ZX in the presence of each endodontic solution. It is concluded that the Root ZX mini and Mini Apex Locator have similar accuracy to the Root ZX and that the function of the three apex locators was not affected by the type of endodontic solution used.

Evaluation of the Raypex 5 and the Mini Apex Locator: An In Vivo Study

Introduction The purpose of this study was to compare the accuracy in vivo of 2 electronic apex locators (EALs), the Raypex 5 and the Mini Apex Locator. Methods The working length (WL) was determined electronically for 40 human root canals by using a K-file and 1 of the 2 EALs. The files were fixed at the WL, and the teeth were extracted. The apical 4 mm of each canal was trimmed to expose the file tip. The samples were observed under a scanning electron microscope, and the distance from the file tip to the point 0.5 mm coronal to the major foramen (the final WL) was measured. The data were analyzed by using Student t test, and significance was set at P < .05. Results No statistically significant differences were found between the Raypex 5 and the Mini Apex Locator devices. The mean distance from the final WL to the file tip was 0.174 ± 0.38 mm for the Raypex 5 and 0.286 ± 0.30 mm for the Mini Apex Locator. In determining the final WL, the Raypex 5 was accurate 75% of the time to ±0.5 mm and 100% of the time to ±1 mm, whereas the Mini Apex Locator was accurate 77.8% of the time to ±0.5 mm and 100% of the time to ±1 mm. Conclusions Under the in vivo conditions of this study, no statistically significant differences were observed between the Raypex 5 and the Mini Apex Locator EALs.

Effect of chloroform, orange solvent and eucalyptol on the accuracy of four electronic apex locators

The aim of this study was to evaluate the effect of three retreatment solutions on the accuracy of four electronic apex locators, the Root ZX mini, the Mini Apex Locator, the Root ZX and the Elements Diagnostic Unit and Apex Locator. Forty extracted single-rooted human teeth were used in this study. The four electronic apex locators were operated according to the manufacturer's instructions to locate the 'apical constriction' in the presence of chloroform, orange solvent or eucalyptol in the canal. The accuracy of each apex locator was not affected by the type of retreatment solution present in the root canal. In addition, the accuracy of the four apex locators was similar in the presence of each of the tested solutions.

Preflaring effects on the accuracy of three electronic apex locators

PURPOSE: To compare the accuracy of three electronic apex locators (EALs) and evaluate the influence of cervical preflaring in them. METHODS: The working length (WL) of thirty extracted human mandibular incisors was determined visually. All teeth were mounted in conducting medium and tested with: Novapex, Mini Apex Locator and Propex II. The electronic WL was determined before and after preflaring with LA Axxess burs. Differences between the electronic and visual WL were calculated and analyzed by Friedman and Wilcoxon tests. Radiographs were taken using the electronic WL of each EAL and the distance between the instrument tip and the radiographic apical vertex was measured. This value was compared to a reference or ideal value (1 mm) by one-sample t test. RESULTS: The Novapex was the most accurate EAL before and after the preflaring procedure, which was confirmed by the radiographic analysis. All EALs tested increased their accuracy after preflaring, but no significant difference was noted for the Novapex. CONCLUSION: The Novapex was more accurate compared to the Mini Apex and Propex II. Preflaring procedure was advantageous for all EALs.

Evaluación in vitro de la exactitud del localizador apical miniapex (sybronendo)

The purpose of this study was to determine the accuracys grade of the mini apex locator in the location of the CDC when this it indicates the measure of 0.0mm, confirmed with the SEM. 84 root canals were taken from permanent extracted lower first molars for periodontics of prostodontics reasons this were separated of the distal roots, cut them to level of the enamel-cementum joint, with a carbide disk to low speed, to later on the COE was made using gates glideen burs # 2y 3, irrigating each one of them with NaOCl to 5.25% and later they were introduced sybronendo K flex files #0.8, 10, or 15 depending of the root canal diameter. The Asakos method was used for determine the work's length, followed step was to fit the files inside of the root canal with fluid resin, subsequently to proceeded to cut the filess handle with a and to observe the position of the D0 of the file with respect to the CDC with the SEM with a magnification of 400X. The results show that in the 85.7 %( 52 roots canals) of the samples the D0 of the file was between 0.0 -0.5mm of the CDC and the 14.3 %( 12 root canals) was for under of the CDC. Test showed no significant differences between measurements demonstrated like that the accuracy of Mini Apex locator in determining the working length of root canals during endodontic treatment.

Ex vivo evaluation of the accuracy and coefficient of repeatability of three electronic apex locators using a simple mounting model: a preliminary report

To compare ex vivo the accuracy and coefficient of repeatability of three electronic apex locators in locating the apical constriction. Thirty-one single-rooted teeth were used. The teeth were sectioned at the cement--enamel junction. A mounting model was used for the measurement of electronic length (EL). The Root ZX-II, the Mini Apex Locator and the Novapex were used for electronic measurements. Each electronic measurement was obtained and repeated. After the last measurement, the file was cemented in place, and the apical 4 mm of each root canal was exposed. The distance from the tip of the file to the apical constriction was determined by three investigators and compared with the corresponding ELs. The coefficient of repeatability of all devices was acceptable: Root ZX-II, 0.04 mm; Mini Apex Locator, 0.10 mm; and Novapex, 0.08 mm. There was little variation in inter-examiner agreement; the rho(C) (Lin) correlation coefficient was 0.83 for examiners 1 and 2, 0.88 for examiners 1 and 3 and 0.99 for examiners 2 and 3. Using the Root ZX-II, 13 of 31 electronic measurements were located at the apical constriction (42%). Otherwise, the tip of the file was not located at the apical constriction in any of the electronic measurements with the other two devices. The Wilcoxon signed rank test did not reveal any statistical difference between the Root ZX-II measurements and the actual length (P = 0.628), but there was a statistical difference between the Mini Apex Locator and Novapex measurements and the actual length position (P < 0.05). The devices tested in this study had a high coefficient of repeatability. The Root ZX-II was accurate, but the Mini Apex Locator and Novapex were not accurate in locating the apical constriction.