Effect of Materials For Interim Restoration on Estimation of Working Length Using Electronic Apex Locator: in vitro Study

ABSTRACT: The aim of this in vitro study was to evaluate measurement accordance using an electronic apex locator for estimation of working length in endodontics when different restorative materials for interim crown restoration are utilized. For this study, 13 single-rooted premolars with endodontic occlusal access cavity were prepared. To establish the working length of each tooth, these were mounted in alginate and with the help of an electronic foramen locator and endodontic file K-file # 15, the working length was established. This length was later compared to the estimated working lengths using different intermediate restoration materials. These materials were: Superior Chemfil, Ketac ™ Molar Easymix and Filtek z350 resin. In the electronic measurements, an acceptable tolerance range of variation up to ± 0.5 mm was considered. Highest discrepancies were considered erroneous. For these measurements, central tendency and dispersion were analyzed. The Bland-Altman method was used, and the ANOVA test with a significance level of p <0,05 for statistic difference. Regarding measurements' acceptability and the type of interim restoration material utilized, 7 were acceptable, and 6 were unacceptable for ChemFil Superior, 12 were acceptable and 1 unacceptable for Ketac™ Molar Easymix, and 11 were acceptable and 2 were unacceptable for Filtek Z350 composite resin. The average difference between all electronic measurements was 0.29 (± 0.44). Chemfill Superior showed the most prominent variation between measurements 0.58 (± 0.45). When using an electronic apex locator, measurements showed statistically significant differences depending on the interim restoration material of choice (p<0.05). In conclusion, the measurement accordance using electronic apex locator to estimation the working length is higher, however the electronic estimation of working length can be significatively affected by the material chosen for interim temporary restoration.

RESUMEN: El objetivo de este estudio in vitro, fue evaluar la concordancia de las estimaciones de longitud de trabajo mediante localizador electrónico de foramen, utilizando diferentes materiales de restauración intermedia coronaria. Para tales fines fueron preparados 13 premolares uniradiculares con cavidad de acceso oclusal endodóntico. Para establecer la a longitud de trabajo de cada diente, estos fueron montados en alginato y con la ayuda de un localizador electrónico de foramen y lima de endodoncia K-file #15 fue establecida la longitud de trabajo. Esta longitud fue comparada posteriormente con las longitudes de trabajo estimadas utilizando diferentes materiales de restauración in- termedia. Estos materiales fueron: Chemfil superior, Ketac™ Molar Easymix y resina Filtek z350. En las mediciones electrónicas, se consideró un rango de tolerancia aceptable de variación hasta ± 0,5 mm. Las discrepancias mayores se consideraron erróneas. Se calcularon medidas de tendencia central y la dispersión. Se utilizó el método de Bland- Altman y la prueba ANOVA con un nivel de significancia de p <0,05. Con respecto a la aceptabilidad de las mediciones y el tipo de material de restauración intermedia, 7 fueron aceptables y 6 fueron inaceptables para ChemFil Superior, 12 fueron aceptables y 1 inaceptable para Ketac ™ Molar Easymix, y 11 fueron aceptables y 2 fueron inaceptables para el compuesto Filtek Z350 resina. La diferencia promedio entre todas las mediciones electrónicas fue de 0,29 (± 0,44). Chemfil Superior mostró la mayor variación entre medicio- nes 0,58 (± 0,45). Las mediciones mostraron diferencias estadísticamente significativas dependiendo del material de restauración intermedio elegido (p <0,05). En conclusión, la concordancia en la estimación de la longitud de trabajo usando localizador electrónico de foramen es alta, sin embargo, puede verse afectada significativamente por el material de obturación intermedio.

Determinación de la Longitud de Trabajo Mediante Localizador Electrónico de Foramen Apical y CBCT a Través del Software 3D Endo de Dentsply Sirona: Estudio Comparativo in vitro / Determination of Working Length Using Electronic Locator for Apex and CBCT with 3D Endo Dentsply Sirona Software: Comparative in vitro Study

RESUMEN: En la historia de la Endodoncia, se han utilizado distintos métodos para determinar la longitud de los canales radiculares, como sensación táctil y radiografías. Últimamente, han adquirido gran importancia los localizadores apicales electrónicos, por su gran precisión. Actualmente se ha incorporado el uso de imagenología con Cone Beam. Debido a que existen muchas formas de medir dicha longitud, es necesario ponerlos a prueba y ver si se asemejan a la técnica gold estándar definida en la literatura como el localizador electrónico de foramen apical. El propósito de esta investigación es determinar si existen diferencias estadísticamente significativas en la medida de la longitud de trabajo entre el localizador electrónico de foramen apical, y el uso de Cone Beam procesado con el software 3D endo de Dentsply Sirona. Para esto, se seleccionaron 30 premolares extraídos; se les tomó un Cone Beam para ser analizados con el software 3D endo y medir la longitud de trabajo. Una vez hecho esto, se realizó manualmente cavidad de acceso y se preparó el tercio cervical con fresas Gates Glidden 1 y 2; luego, los dientes fueron colocados en un modelo Pro Train, que asemejó las propiedades de los dientes en la cavidad oral, para permitir el uso del localizador electrónico de foramen y determinar la longitud de trabajo. Una vez obtenidos los datos, fueron comparados a través del Test de Proporciones (p=0.05 hipotético), dando como resultado p=0,2 lo que indica que no existen diferencias estadísticamente significativas en la medida de la longitud de trabajo entre ambos métodos.

ABSTRACT: Various methods have been used in the history of endodontics, to determine the length of the root canals (working length), such as tactile sensation and X-rays. Recently, apical locators have acquired importance, due to their precision. The use of Cone Beam has now also been incorporated. Because there are many ways to measure this length, it is necessary to test them and see if they resemble the standard gold measurement technique defined in the literature as the electronic apex locators. The purpose of this research is to determine whether there are statistically significant differences in the working length between the electronic apex locators, and the use of Cone Beam processed with the Software 3D Endo by Dentsply Sirona. For this, 30 extracted pre-molars were selected, for Cone Beam tomography and 3D endo Software analysis, to measure the working length. Once this was carried out, cavity preparation was performed manually, and the cervical third approached with gates glidden drills 1 and 2. Subsequently, the teeth were placed in a Pro Train model, which resembled the properties of the teeth in the oral cavity, to allow the use of the electronic apex locators to determine the working length.Once the data were obtained, they were compared through the proportions Test (p = 0.05 hypothetical), resulting in p = 0.2, indicating that there are no statistically significant differences in the working length between the two methods.

An In-vitro Evaluation of Auto Apical Reverse Motion of Tri Auto ZX at Working Length Determined by Dentaport Root ZX

Objective: To evaluate the auto apical reverse motion of Tri Auto ZX at working length determined by Dentaport Root ZX. Study design: Cross-sectional design. Place and duration of study: Department of Operative Dentistry, Islamic International Dental College, and the duration of study was 6 months. Materials and methods: Total 72 extracted teeth were used in the present study and standard access cavities were prepared in all the teeth. For in vitro working of Dentaport Root ZX and Tri Auto ZX an apparatus was designed which used normal saline as the conducting medium to ensure free movement of ions between electrodes of electronic apex locator (EAL). Working length was measured electronically using Dentaport Root ZX and noted as Electronic length (EL). The canals were then prepared using Protpaer files till F2 using Tri Auto ZX and the length at which it starts auto apical revere motion (AAR) was noted as AAR. Results: EL showed a mean of 14.69 ± 1.137 mm and SD of 1.137. Measurement at which Tri Auto ZX started its AAR motion showed that the minimum length of canal was 12.5 mm and maximum length was 17.5 mm with a mean of 14.687 ± 1.089 and SD of 1.087. The difference of root canal length measurements taken by EL and AAR motion of Tri Auto ZX showed a minimum difference of -1.5 mm and a maximum of 1 mm with mean difference of -0.014 ± 0.4819 mm. Out of 72 extracted teeth that were used in the present study the difference between EL and AAR was insignificant (p<0.05). Conclusion: In this study it was also established that not only Root ZX is capable of correct determination of the working length but its canal preparation module i.e. Tri Auto ZX is also capable of preparing the canal at the length determined by Root ZX.

Medición electrónica de la longitud de trabajo en forámenes inmaduros simulados: un estudio ex vivo / Electronic working length measurement in teeth with simulated immature foramens: an ex vivo assay

Objetivo: Evaluar ex vivo la confiabilidad de la medición electrónica de la longitud de trabajo obtenida por dos localizadores apicales en forámenes inmaduros simulados. Materiales y métodos: 20 incisivos centrales superiores humanos extraídos con conductos rectos se dividieron en dos grupos de 10 cada uno. En el grupo A, los conductos y los forámenes se prepararon paralelos hasta un calibre #100. En el grupo B, se procedió de manera similar al grupo A, pero los forámenes se prepararon divergentes. Las raíces se recubrieron con una membrana de intestino porcino simulando el ligamento periodontal y se insertaron individualmente en 20 orificios preparados en la tapa de una cuba de acrílico que contenía hueso bovino particulado humedecido. La tapa fue reposicionada en la cuba cuidando que las raíces quedaran sumergidas en el hueso. Mediante una lima K de tercera serie se determinó la longitud de trabajo con los localizadores apicales RootZx y Mini Apex. Luego, se retiró la tapa con los dientes y las membranas, se los preparó hasta un calibre #120 y se midieron nuevamente. Se repitió el procedimiento preparando los forámenes hasta un calibre #140. Se determinó la longitud de trabajo cuando la pantalla de los localizadores apicales marcaba 0,5. Resultados: Las diferencias entre localizadores apicales no fueron significativas, pero sí lo fueron entre ambos tipos de forámenes al prepararlos hasta un calibre #140. Conclusiones: La medición electrónica ex vivo en dientes con forámenes inmaduros simulados fue confiable excepto cuando se prepararon con calibre #140 (AU)

Aim: To evaluate ex vivo the reliability of two apical electronic localizers to determine the working length in teeth with simulated immature foramens. Materials and methods: Twenty extracted upper central human incisors with straight root canals were assigned to two groups of 10 teeth each. In group A, the canal walls and foramens were prepared parallel to a size #100. In group B, the canals were prepared similar but the foramens were divergent. Each root was surrounded with a porcine intestine membrane simulating the periodontal ligament and then placed through holes prepared on the cover of an acrylic box filled with humid particulate bovine bone. The cover holding the teeth was repositioned taking care that the roots were submerged into the particulate bone. A third series K-file along with Root Zx or Mini Apex apical electronic localizers was used to determine the electronic working length. The cover with the teeth and membranes was then removed, the canals were over-prepared to a #120 size file and the electronic working length was measured, then the foramens were widened to a #140 size and the measurements were repeated. The working length was determined when the apical electronic localizers showed 0.5 on the screen. Results: No significant differences were observed between the apical electronic localizers, while significant differences were detected between both types of foramens when prepared to a size #140 (AU)

Un modelo didáctico ex vivo para la medición electrónica de la longitud de trabajo en la enseñanza de grado y posgrado / An ex vivo didactic model for electronically determination of the working length in undergraduate and graduate training

El propósito de este artículo es presentar un modelo didáctico ex vivo para la determinación electrónica de la longitud de trabajo, mediante el empleo de elementos con propiedades similares a los tejidos perirradiculares humanos. El modelo es especialmente aplicable a la enseñanza de grado y posgrado y permite observar paso a paso, en el interior del conducto radicular, de qué manera se desarrolla el proceso de medición electrónica (AU)

The purpose of this article is to describe an ex vivo didactic model to determine the working length using elements with properties similar to periradicular human tissues that are available. The model is specifically designed to be used by undergraduate and graduate students and allowed step by step visual observation of the operation of electronic canal length measuring devices (AU)

Longitud de trabajo electrónica con Raypex 6 en conductos de molares inferiores / Electronic work length with Raypex 6 in lower molars canals

Resumen: Objetivo: Evaluar la precisión de Raypex 6 para localizar el foramen y ubicarse en la zona cemento dentina conducto (CDC) en conductos de molares inferiores por medio de diafanización. Material y métodos: 52 conductos permeables de 20 molares inferiores extraídos inmersos en alginato fueron utilizados. Se realizó abertura coronaria, localización, permeabilización e irrigación con hipoclorito de sodio al 5.25%. Con el localizador electrónico Raypex 6 se obtuvo conductometría electrónica. Se introdujo lima tipo K #15 o 20 en cada muestra que tenía el clip labial inserto en alginato. La pantalla del dispositivo indicó la posición del foramen apical en la barra roja y se procedió a reajustar la posición de la lima K en las dos primeras barras amarillas y la lima se fijó con resina acrílica. Los dientes se diafanizaron por medio de la técnica de ácido nítrico y se mantuvieron en salicilato de metilo. Las muestras se analizaron con microscopio clínico a 16x y de manera subjetiva se asignó el valor de preciso, si la punta de la lima se ubicó entre 0 a -0.5 mm, fuera o positivo (+) si la lima estuvo +0.1 mm o más y corto o negativo (-) si fue de -0.51 mm o menos con respecto al foramen apical. Resultados: De las 52 muestras analizadas, se encontraron 40 precisas, siete largas y cinco cortas. La estadística descriptiva demostró 76.9% de precisión. Conclusión: La longitud de trabajo electrónica con Raypex 6 mostró una adecuada precisión en conductos mesiales de molares inferiores.

Abstract: Objective: To assess precision of Raypex 6 to locate foramen and establish placement in the canal -dentin-cement (CDC) area in lower molar canals by means of diaphanization. Material and methods: 52 permeable canals from 20 extracted lower molars immersed in alginate were used. Crown opening, location, permeabilization and irrigation with 5.25% sodium hypochlorite were performed. Electronic conductometry was obtained with Raypex 6 electronic locator. A K #15/20 file type was inserted in all samples which had labial clip inserted in alginate. The device's screen indicated position of the apical foramen in the red bar, K files position was readjusted in the first two yellow bars, the file was then fixated with acrylic resin. Teeth were diaphanized by means of the nitric acid technique; teeth were kept in methyl salicylate. Samples were analyzed with clinical microscope at 16x, they were subjectively assigned a value called precise when the tip of the file was located at 0-0.5 mm, external or positive (+), when the file was +0.1 mm or more, and short or negative (-) when it was -0.51 mm or less with respect to the apical foramen. Results: Of the 52 analyzed samples, 40 were found to be precise, seven long and five short. Descriptive statistics showed 76.9% precision. Conclusion: Electronic working length with Raypex 6 showed suitable precision in mesial canals of lower molars.

Evaluación del ajuste apical y la adaptación de los conos de gutapercha ProTaper Next, ProTaper Gold, WaveOne Gold y Reciproc Blue en conductos simulados instrumentados con estos sistemas / Evaluation of the apical tugback and adaptation of ProTaper Next, ProTaper Gold, WaveOne Gold and Reciproc Blue gutta-percha cones in simulated canals prepared with these systems

Objetivo: Evaluar el ajuste y la adaptación apical de los conos de gutapercha de cuatro diferentes sistemas de instrumentación y obturación endodóntica en conductos curvos simulados. Materiales y métodos: Se emplearon 4 Endo Training Blocks (Dentsply Sirona) con conductos curvos simulados, instrumentados hasta el límite de trabajo, fijado en el orificio de salida del conducto. Con ese propósito se empleó un tope metálico confeccionado ad hoc, ajustado en la concavidad de la salida del conducto, a fin de asegurar el límite de la instrumentación en todos los bloques de trabajo. El tope metálico se mantuvo en la posición por medio de una morsa de mesa. Los conductos fueron permeabilizados con una lima tipo K #10 (Dentsply Sirona). A continuación, se procedió con los protocolos de instrumentación de los sistemas por evaluar en cada Endo Training Block. Se emplearon los sistemas ProTaper Next (Dentsply Sirona), ProTaper Gold (Dentsply Sirona), WaveOne Gold (Dentsply Sirona) y Reciproc Blue (VDW) de acuerdo con las especificaciones del fabricante (grupos 1, 2, 3 y 4 respectivamente). Los conductos fueron irrigados con agua destilada a cada cambio de instrumento y al finalizar la preparación, y secados con conos de papel. Luego se evaluaron, en el respectivo Endo Training Block, el ajuste y la adaptación apical a la longitud de trabajo de 10 conos de gutapercha del sistema correspondiente. Para la evaluación del ajuste, se introdujeron los conos de gutapercha en el conducto simulado respectivo y se elevaron ambos hasta 10 cm de altura, manteniéndolos durante 10 segundos. Cuando se conservaban en esa situación, se consideraba que el cono ajustaba; si se desprendían antes de ese lapso, se establecía la falta de ajuste. Así mismo, se constató en cada caso su adaptación apical a la longitud de trabajo con un microscopio clínico operativo a 8,5X. Para la evaluación total se consideraron las siguientes categorías: 1, el cono de gutapercha llegaba a la longitud de trabajo y ajustaba; 2, el cono de gutapercha llegaba a la longitud de trabajo, pero no ajustaba; 3, el cono de gutapercha no llegaba a la longitud de trabajo; y 4, el cono de gutapercha sobrepasaba la longitud de trabajo. Resultados: Entre los grupos 1, 3 y 4 no se observaron variables intrasistemas de ajuste y adaptación apical a la longitud de trabajo. En el grupo 2 sí las hubo, pero la diferencia entre grupos no fue significativa (P>0,05). Conclusiones: De los cuatro sistemas utilizados, en tres de ellos el empleo de un cono único de gutapercha garantizó, en todas las pruebas, la adaptación y el ajuste a la longitud de trabajo (AU)

Aim: To evaluate in the tugback and apical adaptation at the working length of four different mechanized systems gutta-percha cones in simulated curved canals. Materials and methods: Four Endo Training Blocks (Dentsply Sirona) with simulated curved canals were instrumented up to the working length established at the orifice located in the canal exit. A metal stop was adjusted in the concavity present at the exit of the canal to ensure the working length during instrumentation in all blocks. The metal stop was maintained using a table walrus. Canal patency was achieved with a #10 K file (Dentsply Sirona). Then the instrumentation protocols for the different systems were performed in each Endo Training Block. ProTaper Next (Dentsply Sirona), ProTaper Gold (Dentsply Sirona), WaveOne Gold (Dentsply Sirona) and Reciproc Blue (VDW) were used according to the manufacturers' instructions (groups 1, 2, 3 and 4 respectively). The canals were irrigated with distilled water between instruments and at the end of the preparation and dried with paper points. Then, the tugback and the apical adaptation at the working length of 10 gutta-percha cones of each system were evaluated in the corresponding Endo Training Block. For the tugback analysis, the gutta-percha cones were introduced in the respective simulated canal and both were raised up to 10 cm in height, holding them for 10 seconds. If the cones remained intact in their position, it was considered that the cone tugback was appropriate, if the cones were detached, a lack of tugback was considered. Likewise, a clinical operating microscope at 8.5X was used to confirm the apical adaptation to the working length in each case. For the overall evaluation the following categories were considered: 1, the gutta-percha cone reached the working length with tugback; 2, the gutta-percha cone reached the working length without tugback; 3, the gutta-percha cone did not reach the working length; 4, the gutta-percha cone exceeded the working length. Results: In three groups 1, 3 and 4 they were not found intra-systems variables in the tugback at the working length. In one group there were observed intra-systems variables but the differences between groups were not statistically significant (P>0.05) (AU)

Comparative analysis of two electronic apex locators in working length determination using stainless steel and nickel titanium hand files in permanent teeth with simulated apical root resorption – An in vitro study

Background: Exact estimation of root canal length is imperative for the achievement of root canal treatment. Working length (WL) has been defined as „„the distance from a coronal reference point to the point at which canal preparation and obturation should terminate‟‟. Aim: The aim of this study was to evaluate and compare the accuracy of two generations of apex locators in teeth with simulated apical root resorption using stainless steel and nickel titanium hand files. Materials and methods: Eighty single-rooted, maxillary anterior teeth were selected. The extracted teeth were soaked in 5% sodium hypochlorite for 6 hours and then in sterile 0.9% saline until use. An oblique cut of 45 degree was made from facial to palatal wall. Access cavities were prepared and the Haneen Al Otheem, Swati Srivastava, Shahad Alogayyel, Maymonah Abdurhman Alghadouni. Comparative analysis of two electronic apex locators in working length determination using stainless steel and nickel titanium hand files in permanent teeth with simulated apical root resorption - An in vitro study. IAIM, 2018; 5(5): 45-50. Page 46 Visual Working Length (VWL) was measured. The samples were then embedded in alginate and the electronic measurements were recorded using stainless steel and nickel titanium hand files. Statistical analysis was done by Analysis of variance (ANOVA) followed by Tukey HSD test were used for statistical analysis. Results: There was no statistically significant difference seen with DentaPort ZX and i-Root along with the use of stainless steel and NiTi hand files. Conclusion: In the present study, DentaPort ZX and i-Root apex locators showed similar efficacy in determining working length with the use of both stainless steel and NiTi hand files under present study conditions

Modified Bisecting Angle Technique: A Novel Method to Eliminate Zygomatic Superimposition over the Apices of Maxillary Molars

Objectives Intra oral radiographic imaging is the most widely used method for obtaining information about root canal anatomy and working length determination. Measuring exact working length is the most essential step for the success of root canal treatment. Bisecting angle technique (BAT) is the most widely used technique for this purpose. However, zygomatic superimposition over the apices of maxillary molars makes it difficult for the dentist to estimate exact working length. The present study made certain modifications in BAT to overcome these undiagnostic shadows. The aim of the study is to compare three techniques, namely paralleling cone technique (PCT), BAT and modified bisecting angle technique (MBAT) to prevent such superimposition over molar apices. Materials and Methods A total of 53 patients requiring endodontic treatment for maxillary molars were included in the study. Three radiographs one with each PCT, BAT, MBAT were made. Each radiographic image was recorded acceptable or unacceptable based on the zygomatic superimposition. The data thus collected was subjected to statistical analysis using chi-square test. Results The percentage of acceptability in MBAT was 56.6% (n = 30) when compared with BAT which was only 28.3% (n = 15) and PCT was 58.3% (n = 31) indicating statistically significant difference between BAT and MBAT. But no statistically significant difference was found between MBAT and PCT. Conclusion In the present study, MBAT was found to be more accurate than BAT, and it was relatively as accurate as PCT in eliminating zygomatic superimposition over the apices of maxillary molars.

Evaluación de un modelo de capacitación preclínica en el uso de los localizadores electrónicos del foramen, por alumnos de grado de endodoncia / Evaluation of a preclinical training model of undergraduatestudents in the use of electronic foramen locatorsin endodontics

Objetivo: evaluar la capacitación y los resultados del uso de localizadores del foramen en un curso preclínico destinado a alumnos de grado de la Escuela de Odontología de la Universidad del Salvador / AsociaciónOdontológica Argentina, entre 2005 y 2016. Materiales y métodos: Se emplearon 2053 incisivos, caninos y premolares inferiores y superiores humanos extraídos. Los dientes se montaron de modo tal que sus raí-ces quedasen sumergidas en una solución salina, utilizando dos métodos: a) tubos de plástico, b) modelos que simulan la arcada dentaria. Se realizaron los accesos coronarios al conducto radicular de forma convencional y se prepararonlos tercios cervical y medio. Para determinar la longitud de trabajo, se introdujo una lima tipo K de calibre acorde con el conducto radicular, ajustando en ella el terminal del localizador electrónico del foramen. El terminal labial se sumergió en la misma solución salina en que se encontraban las raíces dentarias. En la mayoría de los dientes se empleó, parala determinación, la técnica de ingreso, y en los restantes, la de regreso. El nivel de penetración se estableció con la señal lumínica y/o sonora de 0,5. Se ajustó el tope del instrumento al borde de referencia y se obtuvo una imagen radiográfica periapical del diente evaluado. Se retiró el instrumento del conducto radicular y se midió desde su punta hasta el tope respectivo. Las medidas obtenidas con los localizadores electrónicos del foramen se compararon con las conductometrías radiográficas, considerando una tolerancia de 0,5 mm. Para la evaluación estadística, se tomó en cuenta el cálculo de intervalo deconfianza (95 por ciento) realizado a partir de la distribución binomial.Resultados: De los 2053 dientes en los cuales se determinó la longitud de trabajo, 1743 (84,9 por ciento) fueron consideradas medidas correctas, y 310 (15,1 por ciento), incorrectas...

Aim: To assess the training process and results of the useof electronic apex locators in an Aim: To assess the training process and results of the useof electronic apex locators in an undergraduate preclinicalcourse for students from the University del Salvador / AsociaciónOdontológica Argentina between 2005 and 2016.Materials and methods: Two thousand fifty threeextracted human incisors, canines, maxillary and mandibularbicuspid teeth were used. The teeth were mounted withthe roots submerged in saline solution using two methods: a) plastic tubes, b) models simulating the dental arch. Conventionalcoronal access to the root canal was performedand the cervical and middle portions of the root canal wereflared. To determine the working length a K-file with a caliberaccording to the root canal was selected for each tooth andintroduced in the root canal with the clip adjusted in the file.The labial clip was immersed in the model saline solution. Inthe majority of the teeth the advanced and withdrawal techniquewas employed. The level of penetration was establishedusing the light and/or the acoustic signal at 0.5. Then, the rubberstop was adjusted to the reference line and a radiographwas obtained. The instrument was removed and measuredfrom its tip to the rubber stop. The measurements obtainedwith the electronic apex locators were compared with thoseobtained from the X rays considering a tolerance of 0.5 mm.For the statistical evaluation, 95% confidence intervals werecalculated using the binomial distribution.Results: Out of 2053 teeth in which the working lengthwas determined, 1743 (84.9%) were considered correct measurementsand 310 (15.1%) incorrects...

In vivo assessment of accuracy of Propex II, Root ZX II, and radiographic measurements for location of the major foramen

OBJECTIVES: The aim of this in vivo study was to assess the accuracy of 2 third-generation electronic apex locators (EALs), Propex II (Dentsply Maillefer) and Root ZX II (J. Morita), and radiographic technique for locating the major foramen (MF). MATERIALS AND METHODS: Thirty-two premolars with single canals that required extraction were included. Following anesthesia, access, and initial canal preparation with size 10 and 15 K-flex files and SX and S1 rotary ProTaper files, the canals were irrigated with 2.5% sodium hypochlorite. The length of the root canal was verified 3 times for each tooth using the 2 apex locators and once using the radiographic technique. Teeth were extracted and the actual WL was determined using size 15 K-files under a × 25 magnification. The Biostat 4.0 program (AnalystSoft Inc.) was used for comparing the direct measurements with those obtained using radiographic technique and the apex locators. Pearson's correlation analysis and analysis of variance (ANOVA) were used for statistical analyses. RESULTS: The measurements obtained using the visual method exhibited the strongest correlation with Root ZX II (r = 0.94), followed by Propex II (r = 0.90) and Ingle's technique (r = 0.81; p < 0.001). Descriptive statistics using ANOVA (Tukey's post hoc test) revealed significant differences between the radiographic measurements and both EALs measurements (p < 0.05). CONCLUSIONS: Both EALs presented similar accuracy that was higher than that of the radiographic measurements obtained with Ingle's technique. Our results suggest that the use of these EALs for MF location is more accurate than the use of radiographic measurements.

Influence of Blood on the Accuracy of Raypex 5 and Root ZX Electronic Foramen Locators: An In Vivo Study

Abstract The aim of this study was to evaluate in vivo the accuracy of the Raypex 5 and Root ZX electronic foramen locators (EFLs) in the presence of blood in the root canal space. Forty single-canal teeth scheduled for extraction were selected. Access cavity was prepared and coronal enlargement was carried out. Approximately two drops of blood were collected by finger prick and injected into the root canal space. The electronic working length (EWL) of each tooth by each device was established twice before (NB group) and after (WB group) injecting blood into the root canal. The tooth was extracted and the actual working length (AWL) was determined. Data were analyzed using McNemar's test. The accuracy rates of Raypex 5 and Root ZX within 0.5 mm in the NB group were 88.9% and 91.5%, with 83.3% and 86.2% in the WB group, respectively. There were no significant differences between the accuracy of each EFL in the two groups (p>0.05). Considering the NB and WB groups, there were no statistically significant differences in the accuracy of the EFLs (p>0.05). The presence of blood in the root canal space did not influence the accuracy of the EFLs.

Resumo Este estudo objetivou avaliar in vivo a precisão dos localizadores foraminais eletrônicos (EFLs) Raypex 5 e Root ZX em presença de sangue no canal radicular. Foram utilizados 40 dentes unirradiculares destinados a extração. Foi preparada cavidade de acesso e feita ampliação coronária. Cerca de duas gotas de sangue obtidas por punção digital foram injetadas no canal. O comprimento eletrônico de trabalho (EWL) foi medido duas vezes antes (Grupo NB) e depois (Grupo WB) da injeção do sangue. O dente foi extraído e o comprimento real de trabalho (AWL) foi determinado. Os dados foram analisados com o teste de McNemar. As taxas de precisão a ±0,5 mm de Raypex 5 e Root ZX foram 88,9% and 91,5% no Grupo NB, e 83,3% e 86,2% para o Grupo WB, respectivamente. Não houve diferença significativa entre a precisão de cada um dos EFLs em ambos os grupos (p>0,05). Considerando os grupos NB e WB, não houve diferença significativa entre as precisões dos EFLs (p>0,05). A presença de sangue no canal radicular não influencou a precisão dos EFLs.

Longitud de las piezas dentales en Costa Rica

El profesional en Endodoncia se plantea el dilema de hasta qué punto deben penetrar los instrumentos dentro del conducto. Por esta razón, la longitud real de las diferentes piezas dentales en distintas etnias y zonas geográficas de un mismo país es un dato importante y característico. Este estudio se realizó por medio de un análisis tomográfico en piezas extraídas. Se tomó una muestra representativa de las siete provincias de Costa Rica, utilizando 1470 raíces de 980 piezas dentales, 70 piezas superiores e inferiores, mostrando 210 raíces en su totalidad por provincia. Se logró determinar las longitudes reales de las diferentes piezas dentales de los costarricenses. De acuerdo con la metodología utilizada, la muestra fue probabilística de tipo estratificado, con el fin de asegurar una representación de cada una de las provincias del país; se recolectaron piezas dentales en clínicas dentales privadas y públicas. Los resultados reflejan piezas dentales con medidas que se asemejan a otros estudios realizados en otras partes del mundo.

The great dilemma for the practitioner in endodontics is how far to penetrate with the instruments within the duct. For this reason, the real longitude of the different teeth in various ethnias and geographic zones of the same country is an important and characteristic data. This research was done through a tomographic analysis of the extracted teeth. A representative sample of the seven provinces of Costa Rica was taken, using 1470 roots of 980 teeth, 70 superior teeth and inferior, giving 210 roots in total per province. It was possible to determine the real longitudes of the different teeth of the costaricans. According to the methodology used, the sample was probable of the stratified type with the objective goal of assuring a representation of each one of the provinces of the country; the dental pieces were collected through private and public dental clinics. The results reflect teeth with similar measurements to other studies done in other parts of the world.

Endodontic Management of Variants of C-Shaped Canal: Case Series

A thorough knowledge of the root canal morphology is required for successful endodontic therapy. One of the most important anatomic variations is the C-shaped configuration of the root canal system. The presence of high incidence of transverse anastomoses, lateral canals, and apical deltas makes it difficult to clean and seal the root canal system in these teeth and may complicate endodontic interventions. Meticulous mechanical and chemical debridement of the canal space with additional efforts is essential for complete elimination of pulpal pathology in the anatomical irregularities. Obturation of the canal space also requires special attention as obtaining a three dimensional fill of a C-shaped canal may prove to be a problem due to the various intricacies present within the root canal system. Hence, this case series presents various types of C-shaped canal morphologies of mandibular second molars and their management.

Ex vivo Analysis of Three Electronic Apex Locators Accuracy with Different Settings.

Aims: The correct determination of a root canal length is a fundamental step for an adequate chemical-mechanical preparation and consequently, for a successful endodontic treatment. Electronic apex locators (EAL) were developed to provide fast and reliable working lengths. The aim of the present study was to analyze the accuracy of the Root ZX II, RomiApex A-15, and SmarPex EAL’s to determine the location of apical constriction, with and without the instructions recommended by the manufacturers. Methodology: Fifteen mandibular premolars were randomly selected and root canals were accessed. The real canal length was determined by introducing a #15 K-file until the tip was visualized in the apical foramen, using 40x magnification of an operative microscope. In the sequence, the teeth were inserted in plastic flasks containing floral foam soaked in 0.9% saline solution. The root canals were filled with 1% sodium hypochlorite and the electronic measures were obtained with the selected devices until the “0.0” or the last green bar mark, as showed in devices display, and as per the manufacturers settings recommendation. The data were submitted to statistical analysis with the Friedman and Wilcoxon tests with a 0.05% significance level (p < 0.05). Results: All devices were similar (p > 0.05) and showed precise and acceptable measurements at both times. Without manufacturers setting recommendation, the Root ZX II was the EAL that presented the greater percentage of coincidences with the real teeth length measures (73.33%), followed by the RomiApex A-15 (66.66%) and the SmarPex (40%). After performing the recommended settings the Root ZX II and the SmarPex presented 86.66% of coincidence with the real length, however, only the SmarPex device enhanced the mean precision with the real length (p < 0.05). Conclusion: Considering a clinically acceptable average error of ±0.5 mm, all devices were effective in determining the measurement until the apical constriction. Although, there were no statistical significant difference with and without manufacturers instruction, for Root ZX II, the performance was better when manufacturer instructions were followed.

Efficacy of Electronic Foramen Locators in Controlling Root Canal Working Length during Rotary Instrumentation

Abstract: The present study evaluated the efficacy of electronic foramen locators (EFLs) to control root canal working length during rotary instrumentation and to assess possible reliability variations of different working lengths. Forty-eight human mandibular bicuspids were randomly divided in 2 groups according to the used device, Root ZX II (RZX) and Propex II (PRO). They were further subdivided in 2 subgroups according to the root canal preparation level (0.0 and -1.0). Preparation was performed with the Protaper rotary system using a crown-down technique. RZX was employed on its automatic auto-reverse mode (AAR) and PRO was used with the MPAS-10R contra-angle to monitor the preparation. The last used file (F3) was fixed, and the apical portion of the teeth was worn buccolingually, allowing to measure the extent between the file tip and the apical foramen (AF). The precision values of 0.0 mm and -1.0 mm were 100% and 0.0% for RZX, and 100% and 66.7% for PRO, respectively, with a range of ±0.5 mm. Statistical analysis showed no differences between the groups at 0.0 mm. However, at -1.0 mm, RZX showed the poorest results (0.96±0.11 mm), followed by PRO (0.43±0.23 mm). The difference between RZX and PRO was statistically significant. The EFLs were precise in maintaining the working length during rotary preparation when reaching the AF, but when their penetration was limited, both devices showed decreased precision; the RZX AAR failed in all instances.

Resumo: O presente estudo avaliou a eficiência de localizadores eletrônicos foraminais (LEFs) em controlar o limite apical de instrumentação durante o preparo com instrumentos rotatórios. Adicionalmente, determinou-se possíveis variações quando do emprego de diferentes comprimentos de trabalho. Quarenta e oito pré-molares inferiores humanos foram randomicamente divididos em 2 grupos de acordo com o aparelho empregado, Root ZX II (RZX) e Propex II (PRO). Em seguida foram subdivididos em 2 subgrupos em função do limite de preparo (0,0 e -1,0 mm). O preparo dos canais foi realizado com o sistema Protaper em sentido coroa-ápice. O RZX foi utilizando em sua função auto-reverso automático (ARA) e o PRO associado ao contra-angulo MPAS-10R, foi empregado como ferramenta de monitoramento durante o preparo. O último instrumento utilizado (F3) foi fixado em posição, após o que a porção apical dos dentes foi desgastada permitindo a determinação da distância entre a ponta dos instrumentos e o forame apical (FA). A precisão a 0,0 mm e -1,0 mm foi de 100% e 0,0% para o RZX, e de 100% e 66,7% para o PRO, respectivamente, considerando uma margem de ±0,05 mm. A análise estatística não encontrou diferenças entre os grupos a 0,0 mm, todavia, a -1,0 mm, o RZX ofereceu os piores resultados (0,96±0,11 mm), seguido do PRO (0,43±0,23 mm). Esta diferença foi estatisticamente significante. Os LEFs foram precisos na manutenção do comprimento de trabalho durante o preparo rotatório quando se atingiu o FA, todavia, quando esta penetração foi limitada, ambos os aparelhos perderam em precisão; o sistema ARA do RZX falhou em todos os casos.

Comparison of two different methods of average working length determination in second molars and premolars / Comparación de dos métodos para determinar la longitud de trabajo promedio en segundos molares y premolares

Within the procedures involved in a successful endodontic treatment is the working length (WL) determination. The root canal end must be detected accurately, and a precise control of the WL must be maintained. There are several methods to determine WL. Researchers have published the average teeth length (ATL) to the human permanent dentition. These measurements are used as an anatomical reference. If the WL is evaluated using a radiographic image, it is accepted as clinical success if the limit of the canal sealing is 1 mm coronal to the root apex. One method to determine WL is based in substract 1 mm to ATL. Another method widely used, assert to achieve a more precise WL determination, through the use of an electronic apex locator (AL). Nevertheless, published measures of ATL are still used as anatomical reference, and are used to determine WL in the absence of an AL. The aim of this study was to determine the average WL of second molars and premolars with endodontic treatment indication using a PropexII® AL, and compare these measurements to WL determination using ATL method. A descriptive cross-sectional study with a non-random sample of consecutive cases was executed. Results showed that there were no statistically significant differences between the WL obtained with AL and ATL method in studied teeth, except mesio-buccal canal of second maxillary molars (19.94 mm average using AL, 1.54 mm greater than ATL method 18.40 mm; p= 0.002). The ATL method to determine WL could be used to determine the WL of second molars and premolars in studied population. Further research should be performed to determine if ATL method is safe and reliable to be used in absence of an AL or in patients where this instrument cannot be used.

Entre los procedimientos involucrados en un tratamiento endodóntico exitoso está la determinación de longitud de trabajo (LT). Esta debe mantenerse durante todo el tratamiento, y el extremo del canal radicular (CR) debe detectarse con precisión. Existen varios métodos para determinar LT; los investigadores han publicado la longitud total promedio (LTP) de la dentición permanente humana. Estas mediciones se utilizan como referencia anatómica. Si LT se evalúa usando una imagen radiográfica, se acepta como éxito clínico cuando el límite de la obturación radicular queda 1 mm coronal al ápice radicular. Un método para determinar LT se basa en restar 1 mm a la LTP. Otro método, que permite una determinación de LT más precisa, se realiza utilizando un localizador apical electrónico (LA). Pese a esto último, las medidas publicadas de LTP todavía se utilizan como referencia anatómica, para determinar LT en ausencia de un LA. El objetivo fue determinar LT promedio de los CR de segundos molares y premolares con indicación de endodoncia utilizando LA PropexII®, y comparar estas mediciones con la LT determinada utilizando el método de LTP. Se realizó un estudio descriptivo de corte transversal con una muestra no probabilística de casos consecutivos. No hubo diferencias estadísticamente significativas entre la LT obtenida con LA y el método LTP en los dientes estudiados, salvo en los canales mesio-bucales de segundos molares superiores (19,94mm promedio usando LA, 1,54 mm mayor que el método LTP: 18,40 mm; p= 0,002). El método para definir LT a través de LTP podría utilizarse para determinar LT de segundos molares y premolares en la población estudiada. Se requieren investigaciones posteriores para determinar si el método que utiliza LTP es confiable para ser utilizado en ausencia de un LA o en pacientes en los que este instrumento no pueda ocuparse.

Accuracy of Root ZX mini and Raypex 6 in locating the apical foramen of molars: radiographic and microscopic evaluation

Introduction: The precise localization of the apical foramen and the odontometry determination is an important stage since it locates the apical limit for instrumentation and filling. Objective: To compare the accuracy of Root-ZX Mini and Raypex 6 in locating apical foramen in extracted molars. Material and methods: 80 mesial and buccal canals from 40 mandibular and maxillary human molars were used. A size #15 K-file was introduced to canal, until the locator indicated the apical foramen (red bar/line in both devices). With the file in position, it was re-adjusted for Root-ZX II Mini on the green bar and on the two yellow bars for Raypex 6. All the samples were measured from the tip of the file to the apical foramen with radiovisiograph and the Sidexis software. The apical third of the root was shaved until exposure of the file. The distance from the file tip to the most coronal border of the apical foramen was obtained and it was measured with a clinical microscope at 16-fold magnification. The measured lengths with the radiovisiograph and the clinical microscope were analyzed with the statistical Student's T-test. Results: The average length from the tip of the file to the apical foramen using Root-ZX Mini was 0.695 mm and 0.543 mm with Raypex 6. There was no significant difference. Conclusion: Two devices were accurate in locating apical foramen with an adequate level of reliability.

Effectiveness of three electronic apex locators to determine root canal working length / Efectividad de tres localizadores apicales electrónicos para determinar la longitud radicular de trabajo

This study was to evaluate in vivo the accuracy of three electronic apex locators (EALs) in determining working length (WL) using hand files and a wear technique. Thirty two premolars that were completely formed apically and that were scheduled for extraction for orthodontic reasons from patients between ages of 15 and 20 years old were included. Electronic measurement of WL was performed using the EAL according to the manufacturer’s instructions. The following three EAL were used: A. Root ZX II; B. Raypex 5, and C. Propex II. There were significant difference (p=0.0002) when comparing median differences among the three EAL. Statistical analysis revealed significant differences between Root ZX II vs. Raypex 5 and Root ZX II vs. Propex II (p=0.0044; p=0.0002), while between aypex 5 and Propex II, there were no statistically significant differences with respect to the accuracy of the EAL in determining WL (p=0.1087). The present findings suggest that Root ZX II presented the highest agreement rate for determining the final WL...

Estudio fue evaluar in vivo la exactitud de tres localizadores apicales electrónicos(LAEs) para determinar la longitud de trabajo (LT) usando instrumentos manuales y una técnica de desgaste. Treinta y dos premolares con formación apical completa e indicados para extracción por razones ortodóncicas de pacientes de edad entre 15 y 20 años fueron incluidos en el estudio. Seusaron tres LAE; A. Root ZX II; B. Raypex 5, y C. Propex II. Se encontraron diferencias significativas (p=0.0002) cuando se compararon las medianas entre los tres LAE. El análisismostró diferencias entre Root ZX II vs. Raypex 5 y Root ZX II vs. Propex II (p=0.0044; p=0,0002), mientras queentre Raypex 5 y Propex II, no se encontraron diferencias estadísticamente significativas en la determinación de la LT (p=0.1087). Los presentes hallazgos sugieren que Root ZX II mostró la mayor exactitud para determinar la LT final...

Working width, a deserted aspect of Endodontics

No abstract available.