Canal Cleanliness and Smear Layer Removal Using Different Irrigant Activation Methods - A Scanning Electron Microscopy Study

rrigation is one the most important aspects during root canal treatment of the teeth which can be achieved by mechanical cleaning and shaping with the aid of irrigants. However, the irrigant does not travel to all the places of the root canal especially the apical third. Hence, to make this irrigant reach the apical third, we need irrigant activation methods which will agitate the irrigant and help in accessing the places which are difficult to reach in the root canal system. The objective of this research was to check the canal cleanliness and the removal of the debris after irrigant activation using manual dynamic agitation (MDA), plastic F file, sonic irrigation (SI) and conventional syringe irrigation (CSI). METHODSSixty single rooted teeth were chosen for this study which were biomechanically prepared using ProTaper system (Dentsply Maillefer, USA) up to a preparation of F2 and 3 % NaOCl and 17 % EDTA were used as irrigants. All the samples were equally divided into groups of fifteen each depending on the mode of irrigant activation method used - Group 1, Manual Dynamic Agitation (MDA); Group 2, plastic F file; Group 3, EndoActivator (SI); and Group 4, control group (C). These teeth were then split along the long axis and were observed under the SEM for any debris and to determine the degree of canal cleanliness. RESULTSGroup 4 (control group) showed the maximum debris under SEM with a statistically significant difference with a P value less than 0.05; next was the manual dynamic agitation group. Plastic F file group and sonic irrigation groups showed almost similar results in terms of debris. CONCLUSIONSIrrigant activated using sonic mode and plastic F file efficiently removed the debris in comparison to the other two groups of syringe irrigation and manual dynamic agitation.

Comparación de tres técnicas de irrigación en la remoción de hidróxido de calcio / Comparison of three irrigation techniques in the removal of calcium hydroxide

Objetivos: Comparar la eficacia de tres de protocolos de irrigación en la remoción de hidróxido de calcio (Ca(OH)2) Material y Métodos: Mediante un diseño de estudio comparativo in vitro, se instrumentaron 106 conductos radiculares de incisivos bovinos hasta una lima de diámetro 60, la raíces se fraccionaron en dos mitades siguiendo el eje mayor del diente y se creó un surco estandarizado a 2 mm del agujero apical que fue rellenado con una pasta de hidróxido de calcio, luego se reensamblaron las mitades, se incubaron por 7 días y se realizaron los protocolos de irrigación: ultrasónica pasiva (PUI), sónica con Endo Activator (EA) y activación dinámica manual (MDA), donde se usó como irrigante hipoclorito de sodio (NaOCl) al 5%. Se utilizó un control negativo y positivo. Con un estereomicroscópio se observó la cantidad de residuo, las imágenes se examinaron y se les asignó una puntación de acuerdo a la escala de van der Sluis, finalmente los datos se analizaron con la prueba estadística del Chi Cuadrado. Resultados: Los porcentajes de eficacia para los protocolos de irrigación PUI, EA y MDA fueron del 87,5%; 46,9% y 28,1% respectivamente, la técnica PUI fue superior a EA y MDA y obtuvo diferencias estadísticamente significativas (p<0,001). Conclusiones: PUI fue el método más efectivo en la remoción de Ca(OH)2 de los surcos simulados en los conductos radiculares.

Objectives: To compare efficacy of three irrigation protocols in the removal of calcium hydroxide (Ca(OH)2). Materials and Methods: Through an in vitro comparative study design, 106 root canals of bovine incisors were instrumented up to a file of diameter 60, the roots were fractioned into two halves following the major axis of the tooth and a standardized groove was created 2mm from the apical foramen that was filled with a paste of calcium hydroxide, then the halves were reassembled, incubated for 7 days and the irrigation protocols were carried out: passive ultrasonic (PUI), sonic with Endo Activator (EA) and manual dynamic activation (MDA), where 5% sodium hypochlorite (NaOCl) was used as irrigant. A negative and positive control was used. With a stereomicroscope the amount of residue was observed, the images were examined and assigned a score according to the van der Sluis scale, finally the data were analyzed with the statistical test of Chi-square. Results: The percentages of efficacy for PUI, EA and MDA irrigation protocols were 87.5%; 46.9% and 28.1% respectively, the PUI technique was superior to EA and MDA and obtained statistically significant differences (p <0.001). Conclusions: PUI was the most effective method in the removal of Ca(OH)2 from the simulated grooves in the root canals.

Effect of sonic versus ultrasonic activation on aqueous solution penetration in root canal dentin

The aim of this study was to observe the penetration of an aqueous solution into the root canal dentin under sonic activation and ultrasonic activation. Materials and Method: this study consisted of experimental in vitro research. In order to achieve a closed system, the apex of 45 single-rooted teeth was sealed with wax. The step-back technique was manually performed using a K50 apical master file and 3 groups were organized according to the protocol of the final irrigant activation: group I: non-activated chinese ink for 30 seconds, group II: chinese ink sonically activated with EndoActivator for 30 seconds, and group III: chinese ink ultrasonically activated with Varios 350 equipment for 30 seconds. Teeth were sectioned longitudinally, and the samples obtained were observed under a stereomicroscope at 1X magnification in order to be photographed and scanned to calculate the penetration area using the Image J software. The tinted radicular area was evaluated in relation to the total area of the root dentin. The tukey's post-hoc test and ANOVA were used for the statistical analysis (p<0.05). Results: group I and II obtained 9.13 percent and 9.42 percent penetration respectively, while in group III the highest degree of dye infiltration was achieved (13.9 percent), being statistically significant (p<0.001). Conclusions: ultrasonic activation produced a significantly higher penetration of the dye when compared to conventional activation and sonic activation.

Activación sónica versus ultrasónica de EDTA al 10% para remoción de barrillo dentinario en el tercio apical del canal radicular / Sonic versus ultrasonic activation of 10% EDTA for smear layer removal in the root canal apical third

El objetivo de este estudio fue evaluar la efectividad de la activación sónica y ultrasónica del ácido etilendiaminotetraacético (EDTA) al 10% para remover barrillo dentinario en el tercio apical y el grado de erosión producido sobre las paredes del canal radicular. Se realizó un estudio cuantitativo experimental in vitro. Se instrumentaron 40 dientes manualmente con la técnica step-back hasta lima maestra número 55 y fueron asignados a 4 grupos según protocolo de irrigación final: I: agua destilada estéril sin activación, II: EDTA 10% sin activación por 30 segundos, III: EDTA 10% activado sónicamente por 30 segundos y IV: EDTA 10% activado ultrasónicamente por 30 segundos. Las muestras fueron observadas en MEB a una magnificación de 5000X. Se evaluó la presencia de barrillo dentinario remanente y grado de erosión según criterios de Torabinejad et al. Para el análisis estadístico se utilizó la prueba de Kruskal-Wallis y Post Hoc de Tukey con un nivel de significancia 5% (p=0,05). El grupo I (agua sin activación) presentó mayor cantidad de barrillo que el resto de los grupos (p<0,01). En cuanto a la presencia de barrillo, entre los grupos II (EDTA sin activación), III (EDTA con sonido) y IV (EDTA con ultrasonido) no hubo diferencias estadísticamente significativas. En cuanto a la erosión, el grupo II presentó una mayor erosión que el resto siendo significativa con los grupos I y III (p=0,006). Entre los grupos I, III y IV no hubo diferencias estadísticamente significativas. La activación sónica y ultrasónica del EDTA 10% no produjo una remoción de barrillo significativamente superior al compararlo con la irrigación convencional, pero sí hubo diferencias en cuanto a erosión, siendo menor con la activación sónica

The purpose of this study was to observe the effect of passive sonic and ultrasonic irrigation with 10% Ethilenediaminotetracethic acid (EDTA) on smear layer of the apical third of instrumented root canals as well as the level of erosion produced on the canal walls. For this quantitative experimental in vitro study 40 teeth were hand instrumented with step back technique until master file num 55 and divided in four groups according to the final irrigation protocol: I: distilled water without activation, II: 10% EDTA for 30 seconds without activation, III: 10% EDTA sonic activated for 30 seconds, IV: 10% EDTA ultrasonic activated for 30 seconds. Samples were prepared for MEB observation at 5000X. The presence of smear layer and erosion on dentine walls was quantified according to Torabinejad et al. criteria. Data were submitted at Kruskal-Wallis test and Tukey Post Hoc with a significance level of 5% (P=0.05). When evaluating the smear layer presence, there were no statistically significant differences between the groups II, III and IV. Group I had a highest amount of smear layer (p<0.01). As for erosion, group II showed higher erosion than the others, being significant with groups I and III (p=0.006). Among groups I, III and IV there were not statistically significant differences. Sonic and ultrasonic activation of EDTA 10% did not produce a significantly superior removal of smear layer when compared with conventional irrigation. Erosion of root canal walls was significantly lower after sonic activation