A comparative study of smear layer removal and erosion in apical intraradicular dentine with three irrigating solutions: a scanning electron microscopy evaluation

Introduction: This study compared the efficacy of BioPure MTAD (Dentsply Tulsa, Tulsa, OK), 17% EDTA, and 42% citric acid in endodontic smear layer removal and degree of erosion in the apical third of endodontic canals. Methods: Ninety-six extracted single-rooted human teeth were randomized into four groups (n = 24) and instrumented using System GT nickel-titanium rotary instruments (Dentsply Tulsa, Tulsa, OK). Each canal was irrigated with one of the following solutions: BioPure MTAD, 17% EDTA, 42% citric acid, or 5.25% NaOCl (control). Next, all specimens were irrigated with 5.25% NaOCl. Results: Evaluation by scanning electron microscopy showed no significant differences among test irrigants in removing the smear layer. However, the efficacy of BioPure MTAD and 17% EDTA in removing the smear layer was significantly greater than 5.25% NaOCl (control). The erosive effects of irrigating solutions could not be evaluated. Conclusions: In conclusion, the protocols used in this study were not sufficient to completely remove the smear layer in the apical third of prepared root canals. © 2009 American Association of Endodontists

Accuracy of three electronic apex locators in anterior and posterior teeth: an ex-vivo study.

Abstract Introduction: The aim of this study was to determine in anterior teeth, bicuspids, and molars (1) the accuracy of 3 different electronic apex locators (EALs) in detecting the apical foramen and (2) the accuracy of digital radiography in determining the working length (WL), compared with visible control under a microscope. Methods: By using radiovideography (RVG), we measured the lengths of 120 root canals with 3 different EALs (Endex, ProPex II, and Root ZX) and compared them with the actual lengths. The accuracy of EALs and RVG was related to each dental category. An endodontic training kit (Pro-Train) was used during experimental procedures. Results: Statistical analysis showed that the 3 EALs and RVG were less accurate in anterior teeth and molars than in bicuspids. The paired-sample t test showed no statistically significant difference between mesiodistal plane and buccolingual plane digital radiography in all groups. Conclusions: The 3 EALs tested were more accurate in detecting the apical foramen in bicuspids than in both molars and anterior teeth. Radiographic measurements were not reliable for determining WL in all dental groups in both radiographic planes. (J Endod 2011;37:684–687

Precisione nella determinazione della lunghezza di lavoro mediante localizzatori elettronici d’apice, radiologia digitale e prova visiva: presentazione di una nuova metodica sperimentale di indagine – uno studio ex-vivo. Exact determination of the working length by electronic apex locators, digital radiology, and visual test: presentation of a new experimental research strategy – an ex-vivo study.

Abstract Objectives: This study compared: 1) the accuracy of three different electronic apex locators (EALs) in detecting the apical foramen ex-vivo under clinical conditions; 2) the accuracy of digital radiography and EALs in determining the K-file position in the root canal; 3) the accuracy of two different radiographic planes; (4) the precision of #10, #15, and #20 K-files in electronic measurements; 5) the precision of EALs in relation to the dental anatomy classification (anterior, bicuspids, and molars). Materials and methods: The length of 101 extracted human teeth was measured with three different EALs (Endex, Propex II and Root ZX), with RVG and compared to the actual length. Experimental procedures were performed using an endodontic training kit (Pro-Train). Results: The statistical analysis showed that Endex and Propex II were more accurate than Root ZX in determining the working length (WL). The t-test showed no statistically significant difference of accuracy between the two radiographic planes examined. The t-test showed no significant difference between the three different K-file size measurements. EALs and RVG are less accurate in anterior teeth. Conclusions: To prevent overestimation of the root canal length using the EALs tested, 1 mm should be subtracted from the measurement on the ‘‘APEX’’ mark. Instrument sizes did not affect the accuracy of EALs. EALs showed to be more accurate in determining the WL than RVG. 2011 Societa` Italiana di Endodonzia. Published by Elsevier Srl. All rights reserved

Smear layer removal and canal cleanliness using different irrigation systems (EndoActivator, EndoVac, and Passive Ultrasonic Irrigation) : Field Emission Scanning Electron Microscopic Evaluation in an In Vitro Study.

Abstract Introduction: The purpose of this study was to evaluate the effectiveness of different irrigating methods in removing the smear layer at 1, 3, 5, and 8 mm from the apex of endodontic canals. Methods: Sixty-five extracted single-rooted human mandibular premolars were decoronated to a standardized length of 16 mm. Specimens were shaped to ProTaper F4 (Dentsply Maillefer, Ballaigues, Switzerland) and irrigated with 5.25% NaOCl at 37 C. Teeth were divided into 5 groups (2 control groups [n = 10] and 3 test groups [n = 15]) according to the final irrigant activation/delivering technique (ie, sonic irrigation, passive ultrasonic irrigation [PUI], or apical negative pressure). Root canals were then split longitudinally and observed by field emission scanning electron microscopy. The presence of debris and a smear layer at 1, 3, 5, and 8 mm from the apex was evaluated. Scores were analyzed by Kruskal- Wallis and Mann-Whitney U tests. Results: The EndoActivator System (Dentsply Tulsa Dental Specialties, Tulsa, OK) was significantly more efficient than PUI and the control groups in removing the smear layer at 3, 5, and 8 mm from the apex. The EndoVac System (Discus Dental, Culver City, CA) removed statistically significantly more smear layer than all groups at 1, 3, 5, and 8 mm from the apex. At 5 and 8 mm from the apex, PUI and the EndoVac did not differ statistically significantly, but both performed statistically better than the control groups. Conclusions: In our study, none of the activation/delivery systems completely removed the smear layer from the endodontic dentine walls; nevertheless, the EndoActivator and EndoVac showed the best results at 3, 5, and 8 mm (EndoActivator) and 1, 3, 5, and 8 mm (EndoVac) from the apex. (J Endod 2013;39:1456–1460

FESEM evaluation of smear layer removal from conservatively shaped canals: laser activated irrigation (PIPS and SWEEPS) compared to sonic and passive ultrasonic activation—an ex vivo study

Background: Irrigation of the pulp space is a mandatory step to get rid of all its organic and inorganic content. Activation of the irrigants play a key role in the era of minimally invasive endodontics. The aim of this study was to assess the effectiveness of different irrigants activation methods in removing the smear layer at 1, 3, 5 and 8 mm from the apex from conservatively shaped canals. Methods: Eighty-five human mandibular premolars were selected. Specimens were shaped to TruShape 25/.06 and divided into 5 groups (1 control and 4 test groups) according to the final activation technique (EndoActivator, EA), Ultrasonic (EndoUltra, PUI) and Laser (PIPS and SWEEPS). EDTA (Ethylenediaminetetraacetic acid) followed by NaOCl (Sodium Hypochlorite) and again EDTA were activated for each test group. Specimens were then split longitudinally and observed by Field Emission Scanning Electron Microscopy (FESEM). Blinded evaluation of the presence of smear layer was performed at 1000X magnification, according to a 5-score index system. Comparison between groups were analysed statistically using the Kruskal–Wallis non-parametric analysis of variance. Bonferroni multiple comparison tests were used. Results: At 1 mm only PIPS and SWEEPS performed better than the control group. At 3, 5 and 8 mm from the apex, every activation technique showed statistically significant reduction of smear layer when compared to the control group. PIPS and SWEEPS obtained better cleanliness result compared to EA, while only PIPS was superior to PUI in terms of cleanliness. Conclusions: PIPS and SWEEPS showed the best results in conservative canal preparations. Nowadays, contemporary rotary instruments allow fast and minimally invasive shaping of the endodontic space. In this scenario irrigants’ activation may be regarded as a mandatory step to a favourable clinical outcome

Accuracy of three electronic apex locators compared with digital radiography: an ex vivo study

Introduction: This study compared (1) the accuracy of three different electronic apex locators (EALs) in detecting the apical foramen ex vivo under clinical conditions; (2) the accuracy of digital radiography and EALs in determining the working length (WL) with visible control under a microscope; and (3) the precision of #10, #15, and #20 K-files in electronic measurements. Methods: The length of 101 extracted human teeth was measured with three different EALs (Endex [Osada Electric Co, Tokyo, Japan], ProPex II [Dentsply-Maillefer, Ballaigues, Switzerland], and Root ZX [J. Morita Co, Tustin, CA]), with radio videography (RVG) and compared with the actual length. An endodontic training kit (Pro-Train; Simit Dental, Mantova, Italy) was used during the experimental procedures. Results: Statistical analysis showed that Endex and ProPex II were more accurate than Root ZX in determining the WL. The paired sample t test showed no statistically significant difference between the accuracy of the two radiographic planes examined. The t test showed no significant difference between the three different K-file sizes measurements. Conclusions: Endex and ProPex II were more accurate than Root ZX in determining the actual WL. Instrument sizes of hand files did not affect the accuracy of EALs. EALs showed to be more accurate in determining the WL than RVG. (J Endod 2010;36:2003–2007

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