Final Endodontic Irrigation with 70% Ethanol Enhanced Calcium Hydroxide Removal from the Apical Third.

INTRODUCTION: The purpose of this study was to evaluate the cleanliness of root canal walls and dentinal tubules after attempting to remove the calcium hydroxide dressing with different irrigant solutions and the use of nonactivated irrigation or passive ultrasonic irrigation (PUI). METHODS: After root canal instrumentation, 80 single-rooted teeth were filled with calcium hydroxide mixed with propylene glycol and 0.1% rhodamine B dye and inserted into canals with a Lentulo spiral. The calcium hydroxide dressing was initially removed with 10 mL saline solution and reinstrumentation with the master apical file. Then, the samples were randomly assigned into 8 experimental groups (n = 10) according to the irrigant solution with or without PUI: 2.5% sodium hypochlorite, 17% ethylenediaminetetraacetic acid + 1.25% sodium lauryl ether sulfate (EDTA-T), 37% phosphoric acid, or 70% ethanol. A final flush with 5 mL saline solution was performed. The percentage of clean root canal walls and the depth of clean dentinal tubules were measured with images of confocal laser scanning microscopy. The groups were compared using the 2-way analysis of variance test with the Bonferroni post hoc test for depth analysis and the Kruskal-Wallis with Dunn post hoc test for the perimeter analysis. RESULTS: Irrigation with 70% ethanol presented a significantly higher percentage of clean root canal walls and a higher depth of clean dentinal tubules when compared with irrigation with 2.5% sodium hypochlorite and 17% EDTA-T for both irrigation methods (P < .05). No differences were observed between nonactivated irrigation or PUI protocols (P > .05). CONCLUSIONS: Seventy percent ethanol enhanced calcium hydroxide removal from the apical root third compared with 2.5% sodium hypochlorite or 17% EDTA-T.

Influence of File Motion on Shaping, Apical Debris Extrusion and Dentinal Defects: A Critical Review.

Advances in endodontics have enabled the evolution of file manufacturing processes, improving performance beyond that of conventional files. In the present study, systems manufactured using state of the art methods and possessing special properties related to NiTi alloys (i.e., CM-Wire, M-Wire and R-Phase) were selected. The aim of this review was to provide a detailed analysis of the literature about the relationship between recently introduced NiTi files with different movement kinematics and shaping ability, apical extrusion of debris and dentin defects in root canal preparations. From March 2016 to January 2017, electronic searches were conducted in the PubMed and SCOPUS databases for articles published since January 2010. In vitro studies performed on extracted human teeth and published in English were considered for this review. Based on the inclusion criteria, 71 papers were selected for the analysis of full-text copies. Specific analysis was performed on 45 articles describing the effects of reciprocating, continuous and adaptive movements on the WaveOne Gold, Reciproc, HyFlex CM and Twisted File Adaptive systems. A wide range of testing conditions and methodologies have been used to compare the systems. Due the controversies among the results, the characteristics of the files used, such as their design and alloys, appear to be inconsistent to determine the best approach.

Evaluation of the efficacy of filling material removal and re-filling after different retreatment procedures.

This study analyzed the influence of different retreatment protocols on amount of remaining filling material and amount of new sealer after endodontic retreatment. Forty mandibular molars with curved mesial roots were prepared with ProTaper Universal system, and filled with AH Plus sealer mixed with 0.1% rhodamine B and gutta-percha. After 7 days, the specimens were randomized according to the retreatment protocol (n = 10): ProTaper Retreatment System (PTR); PTR+Orange Oil (PTR+OO); PTR+Passive Ultrasonic Irrigation (PTR+PUI). No retreatment was performed in the control group (CG). After retreatment, the root canals were filled with AH Plus mixed with 0.1% fluorescein and gutta-percha. Samples were evaluated under confocal laser scanning microscopy and analyzed using Image J software. Data were analyzed using Kruskal-Wallis and Dunn tests (p < 0.05). Regarding presence of residual filling, the Kruskal-Wallis test indicated no differences among the different retreatment techniques in the perimeter and the isthmus analyses (p > 0.05); however, PTR+PUI was associated with a lesser amount of residual filling material in the canal area analysis (p < 0.05). In evaluating the new filling, the perimeter analysis showed a lesser amount of new endodontic sealer in the PTR group (p < 0.05). Moreover, the PTR+PUI group presented a significantly greater amount of new endodontic sealer in the canal area analysis (p < 0.05). There was no difference among groups in the isthmus analysis (p > 0.05). It can be concluded that PTR associated to PUI yielded better results in removing root canal filling material from the canal area. However, none of the protocols resulted in root walls completely free of remnants.

Evaluation of the efficacy of filling material removal and re-filling after different retreatment procedures

Abstract This study analyzed the influence of different retreatment protocols on amount of remaining filling material and amount of new sealer after endodontic retreatment. Forty mandibular molars with curved mesial roots were prepared with ProTaper Universal system, and filled with AH Plus sealer mixed with 0.1% rhodamine B and gutta-percha. After 7 days, the specimens were randomized according to the retreatment protocol (n = 10): ProTaper Retreatment System (PTR); PTR+Orange Oil (PTR+OO); PTR+Passive Ultrasonic Irrigation (PTR+PUI). No retreatment was performed in the control group (CG). After retreatment, the root canals were filled with AH Plus mixed with 0.1% fluorescein and gutta-percha. Samples were evaluated under confocal laser scanning microscopy and analyzed using Image J software. Data were analyzed using Kruskal-Wallis and Dunn tests (p < 0.05). Regarding presence of residual filling, the Kruskal-Wallis test indicated no differences among the different retreatment techniques in the perimeter and the isthmus analyses (p > 0.05); however, PTR+PUI was associated with a lesser amount of residual filling material in the canal area analysis (p < 0.05). In evaluating the new filling, the perimeter analysis showed a lesser amount of new endodontic sealer in the PTR group (p < 0.05). Moreover, the PTR+PUI group presented a significantly greater amount of new endodontic sealer in the canal area analysis (p < 0.05). There was no difference among groups in the isthmus analysis (p > 0.05). It can be concluded that PTR associated to PUI yielded better results in removing root canal filling material from the canal area. However, none of the protocols resulted in root walls completely free of remnants.

Root and canal morphology of permanent mandibular incisors / Morfología de raíz y ranal de incisivos molares permanentes

There are no studies in the literature reporting the prevalence of root canal ramifications in samples of lower incisors in the population of northern Brazil. The knowledge of the usual endodontic morphology and its possible anatomical variations is important. The aim of this study was to evaluate the prevalence of canals in the lower incisors in the population of northern Brazil using the descaling and diaphanization method. In addition, external measurements were performed and the direction of the apical foramen was observed. One hundred teeth were used for this study, and 18 % of them had two canals, with type 3 being the most prevalent, and the lowest incidence was type 5. The average length of the teeth was 18.5 mm, with 76.31 % of the teeth having a foramen that coincided with the long axis of the tooth. Prior knowledge of such changes should be considered before endodontic therapy.

No hay estudios en la literatura que reporten la prevalencia de las ramificaciones del canal radicular en muestras de incisivos inferiores en la población del Norte de Brasil. El conocimiento de la morfología dentaria en endodoncia y sus posibles variaciones anatómicas es importante. El objetivo del estudio fue evaluar la prevalencia de canales en los incisivos inferiores en la población del Norte de Brasil utilizando el método de descalcificación y diafanización. Además, se realizaron mediciones externas y se observó la dirección del foramen apical. Cien dientes fueron utilizados en este estudio, 18 % tenían dos canales, siendo el tipo 3 el más prevalente, y solo un diente presentó el tipo 5. La longitud promedio de los dientes fue de 18,5 mm, de los cuales en el 76,31 % de éstos se observó un foramen que coincidió con el eje longitudinal del diente. El conocimiento previo de éstas variaciones debe ser considerado antes de la terapia endodóntica.