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INTRODUCTION: The purpose of this study was to evaluate whether the mixing method of AH Plus Jet sealer affects its physicochemical and mechanical properties. METHODS: The properties of AH Plus Jet sealer were analyzed when mixed using either the Auto Mix Tip or manual mixing. The evaluated properties included radiopacity (n = 5), initial and final setting times (n = 5), flow (n = 5), and solubility (n = 3), following specifications outlined in ISO 6876/2012 and ADA Nº 57/2000. pH levels were measured at intervals of 3, 24, 72, and 168 hours (n = 10). The push-out bond strength test was conducted using a universal testing machine and using bovine teeth (n = 30). Failure modes were analyzed with stereomicroscopy. Porosity was evaluated under micro-CT (n = 5), and scanning electron microscopy was also performed (n = 5). One-way analysis of variance and Tukey, unpaired t-tests, or Mann-Whitney tests were used with a significance level of 5%. RESULTS: The Auto Mix exhibited a radiopacity value of 12.11 mmAl, whereas manual mixing resulted in 12.55 mmAl (P > .05). For initial and final setting times, Auto Mix showed 901 minutes and 1779 minutes, respectively, while manual mixing recorded values of 631 minutes and 1504 minutes (P < .05). In terms of flow, Auto Mix demonstrated higher values (25.26 mm) than manual mixing (21.71 mm) (P < .05). No statistical differences were observed between the two methods for solubility and pH (P > .05). Manual mixing presented a higher bond strength value (14.52 MPa) than Auto Mix (9.81 MPa) (P < .05). The mixed failure mode was the most frequent outcome for both methods. The highest porosity was observed for Auto Mix (P < .05). Scanning electron microscopy analysis revealed that manual mixing resulted in a smoother surface with fewer pores and smaller, more evenly distributed agglomerates compared to automatic mixing. CONCLUSION: The mixing method employed for AH Plus Jet sealer influences some physicochemical and mechanical properties of the material.

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Objective: This study aimed to investigate of bioactive materials with specific properties, particularly highly plastic bioceramic cements. These materials are being studied extensively due to their potential to maintain pulp vitality and promote tissue regeneration. Material and Methods: Tooth discoloration induced by an experimental tricalcium silicate-based cement (EC) was evaluated and compared with that of Biodentine (BD) and white MTA-Angelus (MTA). Cavities were prepared on the lingual surfaces of thirty-two blocks of healthy bovine incisors. The blocks were chemically cleaned and then subjected to an initial color evaluation (CIELab values) using a spectrophotometer and randomly divided into three experimental groups (n=10); two additional blocks served as controls. After manipulation, the cements were placed in the cavities, which were subsequently restored with composite restorations. After another color measurement (baseline), they were immersed in bottles of distilled water; they were stored at 37 °C and 100% humidity for the entire test period. The color change (ΔE) was measured after 14, 30, 120 and 150 days. ANOVA and Tukey tests showed significant differences after 14 days (EC vs. MTA), 30 days (EC vs. BD) and 120/150 days (EC vs. BD/MTA) (p < 0.05). Results: All tested materials induced ΔE changes, with the EC group showing the least change at the end of the experiment (ΔE=4.08). Conclusion: EC induced less color change over a 5-month period and thus showed color stability over the entire period, whereas BD and MTA showed progressive discoloration. (AU)

Objetivo: O objetivo deste estudo foi investigar materiais bioativos com propriedades específicas, particularmente cimentos biocerâmicos altamente plásticos. Esses materiais estão sendo amplamente estudados devido ao seu potencial para manter a vitalidade da polpa e promover a regeneração dos tecidos. Material e Métodos: A descoloração dentária induzida por um cimento experimental à base de silicato tricálcico (CE) foi avaliada e comparada com a do Biodentine (BD) e do MTA-Angelus branco (MTA). Foram preparadas cavidades nas superfícies linguais de trinta e dois blocos de incisivos bovinos saudáveis. Os blocos foram quimicamente limpos e, em seguida, submetidos a uma avaliação inicial de cor (valores CIELab) usando um espectrofotômetro e divididos aleatoriamente em três grupos experimentais (n=10); dois blocos adicionais serviram como controles. Após a manipulação, os cimentos foram colocados nas cavidades, que foram posteriormente restauradas com compósito. Após outra medição de cor (valor de referência), eles foram imersos em frascos de água destilada; oram armazenados a 37 °C e 100% de umidade durante todo o período de teste. A alteração de cor (ΔE) foi medida após 14, 30, 120 e 150 dias. Os testes ANOVA e Tukey mostraram diferenças significativas após 14 dias (CE vs. MTA), 30 dias (CE vs. BD) e 120/150 dias (CE vs. BD/MTA) (p < 0,05). Resultados: Todos os materiais testados induziram alterações de ΔE, sendo que o grupo EC apresentou a menor alteração no final do experimento (ΔE=4,08). Conclusão: O EC induziu menos alterações de cor em um período de 5 meses e, portanto, apresentou estabilidade de cor durante todo o período, enquanto o BD e o MTA apresentaram descoloração progressiva.(AU)

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The aim of this study was to evaluate the influence of cervical preflaring on the choice of reciprocating file size (Reciproc system) and the difficulty in reaching the working length for instrumentation of molar root canals. A total of 352 human molars were divided into 2 groups of 176 molars each. In the no preflaring (NPF) group, no cervical preflaring was performed. A reciprocating file (R25, R40, or R50) was selected, and instrumentation was performed in accordance with the manufacturer's recommendations. In the preflaring (PF) group, a file was selected, and cervical preflaring was performed with the use of No. 30/.10 or No. 25/.08 orifice shaper instruments. The clinician then selected a new reciprocating file or used the originally selected file to perform the instrumentation as done in the NPF group. Any changes in choice of file after preflaring were documented for the PF group, and the number of insertions required to reach the working length was recorded for both groups. After preflaring, the selected file was changed from R25 to R40 in 20.08% of canals, from R25 to R50 in 0.40% of canals, and from R40 to R50 in 42.14% of canals. After preflaring, 2.88% of the canals with an initial selection of an R50 file required an instrument with a larger diameter for effective preparation. There was a statistically significant difference between the groups for all file size changes (P < 0.001; χ² test). The mean numbers of instrument insertions needed for the NPF and PF groups, respectively, were 4.09 and 2.42 (R25); 3.49 and 2.31 (R40); and 2.70 and 1.81 (R50). There was a statistically significant difference between the groups for all file sizes (P < 0.001; Kruskal-Wallis test). Under the conditions of this study, preflaring enabled a more suitable selection of reciprocating instrument, which, in turn, allowed for fewer insertions of the file up to the working length.

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INTRODUCTION: The obturation quality of the mandibular molar mesial canals and isthmuses with two thermoplastic techniques, ultrasonic vertical condensation (UVC) and continuous wave of condensation (CWC), was evaluated using computed microtomography (µCT). METHODS: Thirty-six human mandibular molars had been previously scanned and analyzed using µCT for mesial roots with morphologically similar isthmuses for this study. Coronal access and confirmation of foraminal patency were performed, and the actual length of the teeth was established using a clinical microscope (40X magnification). The canals were prepared using ProTaper Gold instruments up to #F3, with 2.5% sodium hypochlorite as the irrigant solution, followed by a passive ultrasonic irrigation protocol. The specimens were randomly divided into the UVC and CWC groups based on the obturation technique to be used. Obturation was performed with #F3 gutta-percha cones cemented using AH Plus Jet sealer. The µCT scans were performed after 15 days, and the images were evaluated by a calibrated examiner blinded to the experimental groups to determine the filling rate of the entire canal area, including the main canal and isthmus. Student's t-test was used for statistical analysis; P values ≤0.05 were considered significant. RESULTS: Neither of the thermoplastic obturation techniques achieved complete filling of the canals (86.3% for UVC and 91.4% for CWC), with a statistically significant difference between them (P = .029). CONCLUSIONS: Under the conditions of the study, it can be concluded that none of the techniques completely filled the canal/isthmus of the mandibular molars; however, the CWC exhibited better performance.

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This paper aims to describe a case of endodontic treatment associated with surgical treatment with apical curettage, apicectomy and transsurgical filling of a right upper lateral incisor with extensive periapical lesion. The patient attended the dental office reporting pain, facial swelling and fever. On clinical examination, an increase in extra and intra-oral volume was observed, affecting the bottom of the right upper sulcus; there was a negative response to the sensitivity test on tooth 12. The periapical radiograph showed the presence of an extensive periapical lesion involving the apices of teeth 11 and 12. In light of these findings, conventional endodontic treatment was chosen. The chemical-mechanical preparation was performed with X1-Blue mechanized files associated with 2.5% sodium hypochlorite and, after three changes of intracanal medication with calcium hydroxide, exudation through the canal persisted. Therefore, a periapical surgery was performed with curettage of the lesion, apicectomy and transsurgical obturation associated with AH Plus sealer. After 7 months of follow-up, complete regression of the periapical lesion was observed. In view of the limitations, the success of this case can be attributed to the association of endodontic treatment with the chosen surgical technique, since a repair of the periapical bone radiolucency was observed.

Este trabalho tem como objetivo descrever um caso de tratamento endodôntico associado ao tratamento cirúrgico com curetagem apical, apicetomia e obturação transcirúrgica de um incisivo lateral superior direito com extensa lesão periapical. Paciente compareceu ao consultório odontológico relatando dor, inchaço na face e febre. Ao exame clínico observou-se um aumento de volume extra e intra-oral acometendo o fundo de sulco superior direito; obteve-se resposta negativa ao teste de sensibilidade no dente 12. A radiografia periapical mostrou a presença de extensa lesão periapical envolvendo os ápices dos dentes 11 e 12. Diante dos achados optou-se pelo tratamento endodôntico convencional. O preparo químico-mecânico foi realizado com as limas mecanizadas X1-Blue associado com hipoclorito de sódio a 2,5% e, após três trocas de medicação intracanal com hidróxido de cálcio, a exsudação via canal persistia. Diante disso, foi realizada uma cirurgia periapical com curetagem da lesão, apicetomia e obturação transcirúrgica associada com o cimento AH Plus. Após 7 meses de acompanhamento foi observado a regressão completa da lesão periapical. Diante das limitações, o sucesso desse caso pode ser atribuído à associação do tratamento endodôntico com a técnica cirúrgica escolhida, visto que foi observado um reparo da radiotransparência óssea periapical.

El objetivo de este artículo es describir un caso de tratamiento endodóntico asociado a tratamiento quirúrgico con curetaje apical, apicetomía y obturación transquirúrgica de un incisivo lateral superior derecho con lesión periapical extensa. El paciente acudió a la clínica dental refiriendo dolor, hinchazón en la cara y fiebre. El examen clínico mostró un aumento de volumen extra e intraoral que afectaba al surco superior derecho, con una respuesta negativa a la prueba de sensibilidad en el diente 12. La radiografía periapical mostró la presencia de una extensa lesión periapical que afectaba a los ápices de los dientes 11 y 12. Se optó por un tratamiento endodóntico convencional. La preparación químico-mecánica se realizó con las limas mecanizadas X1-Blue asociadas a hipoclorito sódico al 2,5% y, tras tres cambios de medicación intracanal con hidróxido de calcio, persistía la exudación a través del conducto. Por lo tanto, se realizó una cirugía periapical con curetaje de la lesión, apicetomía y obturación transquirúrgica asociada a cemento AH Plus. Tras 7 meses de seguimiento, se observó una regresión completa de la lesión periapical. Dadas las limitaciones, el éxito de este caso puede atribuirse a la asociación del tratamiento endodóntico con la técnica quirúrgica elegida, ya que se observó una reparación de la radiotransparencia ósea periapical.

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The aim of the present study was to evaluate the influence of ultrasonic activation (UA) on the setting time and flow of four endodontic sealers: AH Plus (AH), Sealer Plus (SP), MTA Fillapex (MTAF), and BioRoot RCS (BIO). Properties were evaluated as required by ANSI/ADA Specification N° 57 (2008); only the size of the specimens was modified. UA was applied using a smooth tapered ultrasonic tip coupled to a piezoelectric ultrasonic device (30% power) on the freshly mixed materials in two cycles of 20 seconds. The results were statistically analyzed using the ANOVA and Kruskal-Wallis tests, followed by the Tukey and Dunn posthoc tests, respectively, depending on the normality of the data. The shortest setting times, initial and final, were, 115 (BIO/UA) and 148.6 (BIO/UA) min, whereas the longest were 1215 (AH) and 1928 (AH) min. The MTAF sealer did not set throughout the experimental period (2880 minutes). Significant differences were observed between BIO and MTAF and the other sealers, with or without UA, both in the initial and final setting time (P < 0.05). UA did not change the initial setting times; however, it reduced the final setting of BIO (P < 0.05). The highest and lowest flow values observed were 25.52 mm (AH/UA) and 18.66 mm (BIO/UA), respectively. The AH sealer, regardless of UA, exhibited higher flow values compared to the other sealers (P < 0.05), except for the MTAF/UA group, which was the only sealer in which UA promoted a significant flow increase (P < 0.05). Under the conditions of the study, it can be concluded that the BIO, under UA, presented the lowest setting time; however, it exhibited the lowest flow values. The MTAF sealer did not reach its final setting. Moreover, the SP groups exhibited intermediate results in all analyses. In summary, only the final setting time of the BIO group and the flow values of the MTAF group were influenced by UA.

O objetivo do presente estudo foi avaliar a influência da ativação ultrassônica (UA) no tempo e fluxo de ajuste de quatro selantes endodônticos: AH Plus (AH), Sealer Plus (SP), MTA Fillapex (MTAF) e BioRoot RCS (BIO). As propriedades foram avaliadas conforme exigido pela Especificação N° 57 (2008) da ANSI/ADA; apenas o tamanho dos espécimes foi modificado. O UA foi aplicado usando uma ponta de ultrassom suave cônica acoplada a um dispositivo ultrassônico piezoelétrico (30% de potência) nos materiais recém-misturados em dois ciclos de 20 segundos. Os resultados foram analisados estatisticamente usando os testes ANOVA e Kruskal-Wallis, seguidos pelos testes póstticos de Tukey e Dunn, respectivamente, dependendo da normalidade dos dados. Os tempos de ajuste mais curtos, iniciais e finais, foram 115 (BIO/UA) e 148,6 (BIO/UA) min, enquanto os mais longos foram 1215 (AH) e 1928 (AH) min. O selador da MTAF não foi colocado durante todo o período experimental (2880 minutos). Foram observadas diferenças significativas entre o BIO e o MTAF e os demais seladores, com ou sem UA, tanto no tempo de ajuste inicial quanto final (P < 0,05). A UA não alterou os tempos de ajuste inicial; no entanto, reduziu o ajuste final da BIO (P < 0,05). Os valores de fluxo mais alto e mais baixo observados foram 25,52 mm (AH/UA) e 18,66 mm (BIO/UA), respectivamente. O selador AH, independentemente do UA, apresentou valores de fluxo mais elevados em comparação com os outros seladores (P < 0,05), exceto para o grupo MTAF/UA, que foi o único selador no qual o UA promoveu um aumento significativo do fluxo (P < 0,05). Nas condições do estudo, pode-se concluir que o BIO, sob UA, apresentou o menor tempo de ajuste; no entanto, exibiu os menores valores de fluxo. O selador MTAF não atingiu seu ajuste final. Além disso, os grupos de SP apresentaram resultados intermediários em todas as análises. Em resumo, apenas o tempo de ajuste final do grupo BIO e os valores de fluxo do grupo MTAF foram influenciados pelo UA.

El objetivo del presente estudio fue evaluar la influencia de la activación ultrasónica (AU) sobre el tiempo de ajuste y flujo de cuatro selladores endodónticos: AH Plus (AH), Sealer Plus (SP), MTA Fillapex (MTAF) y BioRoot RCS (BIO). Las propiedades se evaluaron según lo requerido por la especificación ANSI/ADA N° 57 (2008), sólo se modificó el tamaño de los ejemplares. El AU se aplicó utilizando una punta ultrasónica cónica lisa acoplada a un dispositivo piezoeléctrico ultrasónico (30% de potencia) sobre los materiales recién mezclados en dos ciclos de 20 segundos. Los resultados se analizaron estadísticamente mediante las pruebas ANOVA y Kruskal- Wallis, seguidas de las pruebas postcográficas de Tukey y Dunn, respectivamente, dependiendo de la normalidad de los datos. Los tiempos de fraguado más cortos, inicial y final, fueron 115 (BIO/UA) y 148,6 (BIO/UA) min, mientras que los más largos fueron 1215 (AH) y 1928 (AH) min. El sellador MTAF no se ajustó durante todo el período experimental (2880 minutos). Se observaron diferencias significativas entre BIO y MTAF y los demás selladores, con o sin AU, tanto en el tiempo de ajuste inicial como final (P < 0,05). La AU no modificó los tiempos de ajuste inicial, pero redujo el ajuste final de BIO (P < 0,05). Los valores más altos y más bajos de caudal observados fueron 25,52 mm (AH/UA) y 18,66 mm (BIO/UA), respectivamente. El sellador AH, independientemente del AU, presentó valores de caudal más altos en comparación con los demás selladores (P < 0,05), excepto para el grupo MTAF/AU, que fue el único sellador en el que el AU promovió un incremento significativo del caudal (P < 0,05). Bajo las condiciones del estudio, se puede concluir que el BIO, bajo AU, presentó el menor tiempo de fraguado, sin embargo, presentó los menores valores de caudal. El sellador MTAF no alcanzó su ajuste final. Por otra parte, los grupos SP presentaron resultados intermedios en todos los análisis. En resumen, solo el tiempo de ajuste final del grupo BIO y los valores de flujo del grupo MTAF fueron influenciados por el AU.

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Avaliou-se a influência da utilização da agitação ultrassônica na resistência de união à dentina, por meio de push-out, proporcionada pelos cimentos MTA-Angelus branco (MTA) e Biodentine (BD), empregados no selamento de perfurações de furca. Foram utilizados 48 primeiros ou segundos molares inferiores, com raízes não fusionadas, distantes cerca de 2 mm entre si na porção cervical das mesmas. Os dentes foram acessados e, em seguida, as raízes foram seccionadas transversalmente abaixo da junção cemento-esmalte. Os dentes foram montados em blocos de silicona de adição e perfurações de furca realizadas em seus assoalhos paralelamente ao longo eixo dos dentes e perpendiculares aos assoalhos dentais. A amostra foi dividida em quatro grupos (n = 12) em função do material reparador e da utilização ou não da agitação ultrassônica (AU). Quando empregada, a AU foi aplicada em 2 ciclos de 20 segundos por meio de inserto cônico liso acionado por ultrassom piezoelétrico. Concluídos os selamentos eles foram protegidos com cimento de ionômero de vidro e os dentes imersos em PBS. Decorridos 7 dias discos com 1 mm de altura foram retirados dos assoalhos dentais com auxílio de cortadora metalográfica e levados à máquina de ensaio universal. Os resultados expressos em MPa foram submetidos aos testes ANOVA dois fatores e de Bonferroni. Os maiores valores de resistência obtidos foram no grupo Biodentine com ultrassom (29,41 MPa), seguidos em ordem decrescente pelos grupos Biodentine sem ultrassom; MTA com ultrassom e MTA sem ultrassom (3,72 MPa). Nas condições do estudo concluiu-se que o BD apresentou maior resistência de união à dentina radicular; ainda, que a agitação ultrassônica influenciou positivamente na resistência de união do material à dentina.

We evaluated the influence of the use of ultrasonic agitation on the resistance to the dentin, by means of push-out, provided by the white MTA-Angelus (MTA) and Biodentine (BD) cements, used in the sealing of drilling holes. 48 first or second lower molars were used, with unfused roots, about 2 mm apart in the cervical portion of them. The teeth were accessed and then the roots were sectioned transversely below the cementenamel junction. The teeth were mounted in addition silicon blocks and hole drills performed on their floors parallel along the axis of the teeth and perpendicular to the dental floorings. The sample was divided into four groups (n = 12) depending on the repair material and whether ultrasonic agitation (AU) was used. When employed, the AU was applied in 2 20-second cycles by means of a smooth conical insert activated by piezoelectric ultrasound. Once the seals were completed, they were protected with glass ionomer cement and the teeth immersed in PBS. After 7 days, 1 mm high disks were removed from the dental floorboards with the aid of a metallographic cutter and taken to the universal test machine. Results expressed in MPa were submitted to two-factor and Bonferroni ANOVA tests. The highest resistance values obtained were in the group Biodentine with ultrasound (29.41 MPa), followed in descending order by the groups Biodentine without ultrasound; MTA with ultrasound and MTA without ultrasound (3.72 MPa). Under the conditions of the study, it was concluded that BD showed greater resistance to root dentin binding; also, that ultrasonic agitation positively influenced the resistance of the material to dentin binding.

influencia del uso de la agitación ultrasónica sobre la resistencia de la unión a la dentina se evaluó mediante un estiramiento, proporcionado por los cementos blancos (MTA) y biodentinos (BD) MTA-Angelus, empleados en el sello de los taladros. Se utilizaron los primeros o segundos molares inferiores, con raíces sin fundir, a unos 2 mm de distancia en la porción cervical de las raíces. Se accedió a los dientes y luego las raíces se seccionaron transversalmente por debajo de la unión cemento-enamel. Los dientes se ensamblaron además bloques de silicona y agujeros de perforación en sus pisos a lo largo del eje de los dientes y perpendiculares al suelo dental. La muestra se dividió en cuatro grupos (n = 12) según el material de reparación y si se utilizó o no la agitación ultrasónica (AU). Cuando se empleó, la UA se aplicó en 2 ciclos de 20 segundos mediante una inserción cónica suave activada por ultrasonido piezoeléctrico. Una vez concluidos los sellos, se protegieron con cemento ionómero de vidrio y los dientes se sumergieron en PBS. Al cabo de 7 días, los discos de 1 mm de altura se retiraron del suelo de corte metálico y se llevaron a la máquina de ensayo universal. Los resultados expresados como MPa se presentaron a las pruebas de dos factores ANOVA y Bonferroni. Los valores de resistencia más altos obtenidos fueron en el grupo de Biodentina con ultrasonido (29,41 MPa), seguidos en orden descendente por los grupos de Biodentina sin ultrasonido; MTA de ultrasonido y MTA libre de ultrasonido (3,72 MPa). En las condiciones del estudio se concluyó que la DB mostró mayor resistencia de la unión a la dentina raíz; y que la agitación ultrasónica tuvo una influencia positiva en la resistencia del material a la dentina.

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This study aimed to evaluate the root canal real length (RL) changes due to the mechanical instrumentation use with different flaring magnitudes. After access cavity, 60 mesial root canals of mandibular molars were randomly separated in three groups: Hyflex EDM (HF; #25/.12, #10/.05 e #25/~), Reciproc Blue (RB; R25), and MTwo (M2; #10/.04, #15/.05, #20/.06 e #25/.06). The RL was defined as the apical limit, and 2.5% sodium hypochlorite irrigating solution was chosen. After the access cavity (RL 1), cervical flaring (RL 2), and complete chemical-mechanical preparation (RL 3), the RL was evaluated. The RL was evaluated by a blind examiner with the aid of a microscope (16x) placing the endodontic file stop at the coronary reference. When comparing length measurements, the RL was shorter before instrumentation than that after instrumentation. A reduction of 0.65 mm (HF), 0.61 mm (RB), and 0.48 mm (M2) was observed. However, among groups, no statistical differences were found (p > 0.05). Under the conditions tested, it can be inferred that all mechanical systems provoked RL variations, which emphasizes the need for constant verification of the odontometry, mainly before root canal obturation.

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Abstract This study aimed to evaluate the root canal real length (RL) changes due to the mechanical instrumentation use with different flaring magnitudes. After access cavity, 60 mesial root canals of mandibular molars were randomly separated in three groups: Hyflex EDM (HF; #25/.12, #10/.05 e #25/~), Reciproc Blue (RB; R25), and MTwo (M2; #10/.04, #15/.05, #20/.06 e #25/.06). The RL was defined as the apical limit, and 2.5% sodium hypochlorite irrigating solution was chosen. After the access cavity (RL 1), cervical flaring (RL 2), and complete chemical-mechanical preparation (RL 3), the RL was evaluated. The RL was evaluated by a blind examiner with the aid of a microscope (16x) placing the endodontic file stop at the coronary reference. When comparing length measurements, the RL was shorter before instrumentation than that after instrumentation. A reduction of 0.65 mm (HF), 0.61 mm (RB), and 0.48 mm (M2) was observed. However, among groups, no statistical differences were found (p > 0.05). Under the conditions tested, it can be inferred that all mechanical systems provoked RL variations, which emphasizes the need for constant verification of the odontometry, mainly before root canal obturation.

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Introdução: A descoloração da estrutura dentária representa um grande problema estético e uma das razões mais comuns pelas quais os pacientes vão ao cirurgião-dentista. Objetivo: O objetivo do presente estudo foi avaliar a descoloração dentinária causada pelo emprego dos cimentos obturadores endodônticos AH Plus, MTA Fillapex, Pulp Ca- nal Sealer EWT e Sealer Plus; além de avaliar a influência do uso da agitação ultrassônica (AUS). Métodos: Oitenta blocos de dentes bovinos foram confeccionados e tiveram cavidades circulares preparadas em suas faces palatinas, deixando remanescente de 2,0mm de espessura. Em seguida, os blocos foram randomicamente divididos em função do cimento utilizado e do uso ou não da AUS (n=10). A cor foi mensurada por meio de um espectrofotômetro após a inserção dos cimentos e restauração das cavidades, nos tempos: imediatamente após a inserção dos cimentos (T0 ), após 7 dias (T1 ) e após 180 dias (T2 ). Resultados: Observou-se alteração de cor clinicamente perceptível (ΔE>3,7) causada pelos quatro cimentos obturadores, tanto após 7 dias quanto após 180 dias. Não foram encontradas diferenças significativas entre os grupos nos dois tempos (p>0,05). Conclusões: Pôde-se concluir que os cimentos analisados causaram escurecimento dentinário clinicamente perceptível já após 7 dias, o qual perdurou por todo o período da análise; ainda, que a agitação ultrassônica não interferiu significativamente na ΔE, não influenciando na descoloração dentinária causada pelos cimentos testados (AU).

Introduction: Tooth discoloration is an aesthetic problem commonly reported by patients as one of the main reasons to seek a dentist. Thus, this study aimed to evaluate the dentin discoloration caused by AH Plus, MTA Fillapex, Sealer Plus and Pulp Canal Sealer EWT endodontic sealers, associated or not with ultrasonic agitation during the obturation. Methods: Round cavities were prepared on the palatal faces of eighty bovine teeth slabs, preserving a 2 mm of dentin thickness. The slabs were randomly separated in groups by type of sealer employed and based on the use or not of ultrasonic agitation (n = 10). The color was measured by a spectrophotometer after sealer insertion into the cavities (T0), after 7 (T1) and 180 days (T2). Results: Clinically detectable discoloration (∆E > 3,7) was present in all groups at T1 and T2. Statistically significant differences were not found between T1 and T2 (P > .05). Conclusion: All endodontic sealers tested caused dentin discoloration after 7 days. The color-changing persisted thought the entire experimental period. Moreover, the ultrasonic agitation did not influence on the dentin discoloration caused by the endodontic sealers tested (AU).

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This study aimed to investigate the antimicrobial and biological properties of Ambroxol associated with glycerin (GLI), propylene glycol (PG), and polyethylene glycol (PEG) as a possible vehicle for an experimental tricalcium silicate sealer, with the intention of developing a new biomaterial. Mouse undifferentiated dental pulp cells (OD-21) were cultured, and the effects of different association on cell proliferation and inflammatory cytokine production were investigated. Antimicrobial adhesion of Enterococcus faecalis to setting sealers at 2 h was evaluated. Polyethylene tubes containing experimental sealers and empty tubes were implanted into dorsal connective tissues of 12 male 3- to 4-months-old Wistar rats (250-280 g). After 7 and 30 days, the tubes were removed and processed for histological and immunohistochemical analyses. ANOVA followed by Bonferroni correction and ANOVA followed by Tukey test was used for parametric data and Kruskal-Wallis followed by Dunn for nonparametric (p < 0.05). Cell proliferation was dose-dependent, since all association were cytotoxic at higher concentrations; however, Ambroxol-PEG showed significantly higher cytotoxicity than other association (p < 0.05). In addition, irrespective of the association, no cytokine production was observed in vitro. Ambroxol-GLI reduced bacterial viability, whereas Ambroxol-PEG increased (p < 0.05). Histological examination showed no significant difference in the inflammatory response (p > 0.05) and mineralization ability in all association. Additionally, IL-1ß and TNF-α were upregulated on Ambroxol-PEG in relation to Control at 07 days (p < 0.05). Ambroxol-GLI was the best vehicle for experimental tricalcium silicate sealer, as it promoted an increase in antimicrobial activity without altering the inflammatory response or mineralization ability.

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BACKGROUND: This study aimed to track the toxic ions released by MTA Fillapex, BioRoot RCS, and an experimental tricalcium silicate-based sealer (CEO) into local and distant tissues as well as to investigate their potential adverse effects. In addition, the chemical constituents of the sealers were also evaluated. The main components of the dry powders, pastes, and mixed sealers were characterized. MATERIAL AND METHODS: Dry powder and sealer discs were each set for 72 h and their main components were characterized by energy dispersive X-ray spectroscopy. Polyethylene tubes filled with sealers were used to measure silicon and calcium ions. Polyethylene tubes filled with sealers or empty tubes were implanted into the dorsal connective tissue of Wistar rats. On days 7, 15, 30, and 45, the animals were euthanized and their brains, livers, kidneys, and subcutaneous tissues were removed and processed to determine the concentrations of chromium, cobalt, copper, lead, iron, magnesium and nickel using an inductively coupled plasma optical emission spectrometer. RESULTS: The main compounds in all sealers were carbon, oxygen, silicon, and calcium. MTA Fillapex release more Si while highest levels of Si were found in presence of BioRoot. The release of Si and Ca ions promoted by MTA Fillapex raise by time. No traces of cobalt, chromium, or magnesium were detected in any tissue. Irrespective of the sealer, no traces of copper and lead were found in the subcutaneous tissue; however, they were observed in the organs. The highest concentration of iron was identified in the liver. All sealers exhibited similar nickel traces in the brain, kidney, and liver except for MTA Fillapex, which demonstrated levels higher than CEO in the subcutaneous tissue on day 7. Tracing nickel ions over time revealed that lowest concentrations were found in subcutaneous tissue. CONCLUSION: Taken together, our data demonstrate that CEOs have chemical compositions similar to those of other commercial sealers. Furthermore, none of them exhibited a threat to systemic health. Moreover, the minimal amounts of iron and nickel detected were not related to the sealers.

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Objetivo: O presente estudo teve por objetivo avaliar, ex vivo, a capacidade de elevação do pH da superfície radicular externa de diferentes pastas de hidróxido de cálcio (HC) utilizadas como medicação intracanal, além da influência da ativação ultrassônica (AUS) durante aplicação no interior do canal radicular. Métodos: Foram utilizados 100 incisivos humanos superiores unirradiculares, que tiveram os canais radiculares modelados e divididos aleatoriamente em seis grupos experimentais (n=15), de acordo com a pasta de HC, tendo como variáveis as medicações utilizadas e a ativação da pasta com AUS no momento da aplicação, além de um grupo controle (n=10): Pasta Calen; HC+clorexidina 2% gel (CX2%); e HC + água destilada. Os dentes foram mantidos imersos em água deionizada e as medidas do pH, verificadas nos períodos de 7, 14, 21 e 28 dias, com auxílio de pHmetro. Resultados: De acordo com os dados obtidos, verificou-se elevação do pH nos períodos de 7 e 14 dias em todos os grupos. Apenas os grupos em que foi utilizada a associação do HC com CX2% apresentou evolução com aumento significativo do pH ao longo dos períodos analisados (p<0,05). A ativação das pastas com AUS proporcionou incremento significativo dos valores de pH (p<0,05). Conclusão: De acordo com a metodologia empregada, pode-se concluir que todas as pastas utilizadas promovem elevação do pH no tecido dentinário, e a ativação das pastas com AUS influencia significativamente na elevação do pH no tecido dentinário (AU).

Objective: The aim of the present study was to evaluate, ex-vivo, the pH elevation capacity on the external root surface of different calcium hydroxide (HC) pastes, utilized as intracanal medication, it was also evaluated the influence of the ultrasonic activation at the application within the root canal. Methods: 100 human single root superior incisors were used, which had their root canals shaped and randomly divided into 6 experimental groups (n=15) according to the following HC pastes: Calen; HC + Chlorhex- idine 2% gel (CX2%); HC + distilled water, utilizing the medications and the ultrasonic activation of the paste at the time of the application as variables and 1 control group (n=10). The teeth were kept immersed in deionized water and the pH parameters were verified in 7, 14, 21 and 28 days with a pH measurement machine. Results: According to the data obtained, pH was elevated in the first week in all groups. Only the groups which the association of HC with CX2% was made, did show a significant increase in the pH level over the analyzed periods (p < 0,05). The activation of the pastes with US provided a significant increase in pH values (p < 0,05). Conclusion: According to the methodology used, we can conclude that all the HC pastes used, promote pH elevation in dentin tissue. And the acti- vation of the pastes with US significantly influences the pH increase in dentin tissue

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Sixty moderately curved canals of mandibular molars classified as Vertucci's type IV canal configuration were selected by micro-CT 1174. The teeth were divided into two groups according to the kinematics used, whether reciprocating or rotary motion (n=30, totaling 60 mesial root canals). The instruments used to perform the glide path procedures had identical features (0.15 mm of tip size, 0.04 mm/mm taper, thermal treatment, and square cross-section), but differed in the direction of the cutting blade. The duration of the procedure and the absolute and percentage frequency of the instruments to reach the full working length were recorded. The torsional test (3630-1; 1992) was performed on both used and unused instruments, to evaluate a possible reduction in the torsional resistance when using the glide path procedure. Statistical analysis was performed using the unpaired t-test and the chi-square test, and the level of significance was set at 5%. The type of kinematics used affected the duration of glide path procedures, and the reciprocating motion seemed to induce less torsional stress during glide path procedures.

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Objetivo: O objetivo do presente trabalho foi avaliar a resistência à fadiga cíclica e torcional de instrumentos rotatórios de níquel-titânio com secções transversais semelhantes e confeccionados com diferentes tipos de tratamentos térmicos: Hyflex CM (HCM 25/.06), Vortex Blue (VB 25/.06), Sequence Rotary File (SRF 25/.06) e EdgeSequel (EDF 25/.06) (n=20). Métodos: O teste de fadiga cíclica avaliou o tempo e o número de ciclos para a fratura (NCF) dos instrumentos em canal artificial com 60° de curvatura e 5mm de raio (n=10). O teste de torção avaliou o torque máximo e a deflexão angular para a fratura dos 3mm da ponta dos instrumentos (n=10). Após o teste de torção e de fadiga cíclica, os instrumentos foram avaliados em microscopia eletrônica de varredura (MEV) (n=10). Os dados foram analisados empregando-se os testes ANOVA e de Tukey, sendo selecionado um nível de significância de 5%. Resultados: HCM apresentou o maior tempo e NCF entre todos os instrumentos avaliados (p<0,05). O SRF apresentou um tempo semelhante (p>0,05) e menor NCF (p<0,05) do que o VB. Em relação ao teste torcional, o HCM apresentou menor valor de torque e maior deflexão angular entre os grupos avaliados (p<0,05). Não houve diferenças significativas entre VB, SRF e EDF em relação à deflexão angular (p>0,05). Conclusão: O HCM apresentou maior resistência à fadiga cíclica e deflexão angular. Entretanto, o VB apresentou maior resistência torcional para a fratura (AU).

Objective: The aim of this study was to evaluate the cyclic and torsional fatigue resistance of Nickel-Titanium rotary instruments with similar cross-sectional design and manufactured by different thermal treatments: Hyflex CM (HCM 25/.06) Vortex Blue (VB 25/.06), Sequence Rotary File (SRF 25/.06) and EdgeSequel (EDF 25/.06) (n=20). Material and Methods: Cyclic fatigue test evaluated the time and number of cycles to failure (NCF) in an artificial stainless steel canal with 60° and 5-mm radius of curvature (n=10). The torsional test (ISO 3630-1) evaluated he maximum torque and distortion angle to failure at 3 mm from the tip (n=10). After the torsional and cyclic fatigue test the instruments were evaluated by scanning electron microscope (SEM). Data were analyzed using one-way ANOVA and Tukey tests, and the level of significance was set at 5%. Results: The HCM presented the longest time and highest NCF to fatigue than all the groups (P<0.05). The SRF presented similar time (P>0.05) and lower NCF (P<0.05) to fatigue than VB. Regarding to the torsional test, HCM presented the lowest torque load and the highest distortion angle of all the groups (P<0.05). No significant difference was found among VB, SRF and EDF regarding the distortion angle (P>0.05). Conclusion: The HCM presented the highest cyclic fatigue resistance and distortion angle to failure. However, the VB showed higher torsional load to failure. (AU).

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Taurodontism, usually associated with genetic disorders, is an anomaly in dental development in which the tooth presents with a vertically elongated pulp chamber due to an invagination failure of the Hertwig epithelial sheath. This article presents 2 case reports describing the endodontic treatment of permanent taurodontic molars in systemically healthy patients. In case 1, a maxillary left first molar presented with hypertaurodontism and 5 root canals. In case 2, a mandibular left second molar presented with hypertaurodontism and a C-shaped canal. Treatment of both teeth was based on careful radiographic evaluation with magnification, which allowed the root canal orifices to be identified and the endodontic treatment to be performed. Chemical-mechanical preparation was performed with mechanized instruments and a 2.5% sodium hypochlorite solution. As an auxiliary protocol to finish cleaning, passive ultrasonic irrigation was performed, and a thermoplastic filling technique was used. When complex internal anatomy and accessory root canals are present, endodontic treatment of a tooth presenting with hypertaurodontism can be challenging. Given the complexities of the present cases, the positive outcomes can be attributed to the use of magnification during endodontic procedures and meticulous attention to tooth preparation and obturation techniques.

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This study aimed to evaluate the influence of large apical preparations with Reciproc (REC), Hyflex CM (HCM) and Twisted File Adaptive (TFA) systems using micro-computed tomography (MCT). Ninety mesiobuccal (MB) and distobuccal (DB) root canals of maxillary molars (n = 45) were scanned using MCT before and after the shaping procedures. The root canals (n = 15) were prepared until REC 40.06, HCM 40.04 and TFA 35.04. The root canal transportation (RCT), centring ability (CA), change in volume of the root canal and at different levels (VC), remaining dentine thickness (RDT), removal of dentine wall (RDW) and working time (WT) were evaluated. Data were analysed using the Kruskal-Wallis and Dunn tests, and the one-way ANOVA and Tukey tests with a level of significance set at 5%. No significant difference among the instruments was found regarding the RCT, CA, RDT, RDW and WT (P > 0.05), in larger apical preparations in curved MB and straight DB canals of maxillary molars.

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Abstract: Sixty moderately curved canals of mandibular molars classified as Vertucci's type IV canal configuration were selected by micro-CT 1174. The teeth were divided into two groups according to the kinematics used, whether reciprocating or rotary motion (n=30, totaling 60 mesial root canals). The instruments used to perform the glide path procedures had identical features (0.15 mm of tip size, 0.04 mm/mm taper, thermal treatment, and square cross-section), but differed in the direction of the cutting blade. The duration of the procedure and the absolute and percentage frequency of the instruments to reach the full working length were recorded. The torsional test (3630-1; 1992) was performed on both used and unused instruments, to evaluate a possible reduction in the torsional resistance when using the glide path procedure. Statistical analysis was performed using the unpaired t-test and the chi-square test, and the level of significance was set at 5%. The type of kinematics used affected the duration of glide path procedures, and the reciprocating motion seemed to induce less torsional stress during glide path procedures.

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The aim of this study was to evaluate the influence of different coronal preflaring protocols (absent, conservative and conventional) on the accuracy of Root ZX II, Raypex 6, and RomiApex A-15 electronic foramen locators (EFLs). Twenty mandibular molars with Vertucci's type IV mesial roots were subjected to endodontic exploration and foraminal patency confirmation. Under 16x magnification, its real lengths (RL) were measured and registered (RL1). The canals were then irrigated with 2.5% sodium hypochlorite and electronically measured (EM1) employing the alginate model; all measurements were performed in triplicate by a blind operator using adjusted endodontic hand-files introduced until the apex foramen. Coronal preflaring procedures were sequentially performed with #25/.06 (conservative) and #25/.12 (conventional) instruments; new RLs extents were performed after each coronal preparation protocol (RL2/RL3), as same as electronic measurements (EM2/EM3). The devices error (mm) was evaluated considering the difference between RLs and EMs at each preparation stage; their precision was stablished adopting ±0.5 mm as tolerance margin. The EFLs error significantly reduced after conventional coronal preflaring protocol (p<0.05), which not occur after the conservative one. The best precisions values were noted after conventional preparation as 90% (Root ZX II), 97.5% (Raypex 6), and 92.5% (RomiApex A-15). No significant differences were found in EFLs comparisons, regardless of the coronal protocol tested (p>0.05). Under the conditions tested it can be concluded that the EFLs evaluated were precise. Moreover, the preflaring protocols influences its accuracy's, where the less conservative one produced the best results.

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Objetivo: O presente estudo teve como objetivo comparar três sistemas de instrumentação de NiTi, tratados termicamente, quanto ao número de condutos instrumentados até a fratura. Métodos: Foram utilizados 210 molares humanos inferiores e superiores com curvaturas leves a moderadas, comprimentos reais entre 19 e 21 mm e forames apicais até 200µm. Esses foram randomicamente divididos em três grupos de acordo com o sistema de instrumentação utilizado: Reciproc (REC; R25), ProDesign Duo Híbrido (PDH; #25/.01 e #25/.08) e TF Adaptive (TFA; #25/.08). Foram utilizados 5 instrumentos/kits de cada sistema. Registrou-se, então, o número de condutos instrumenta- dos até a fratura e o número de reinserções necessárias até o alcance do comprimento de trabalho. Resultados: A análise estatística apontou diferenças significativas quando comparada a durabilidade dos sistemas, tendo os instrumentos do grupo PDH oferecido os maiores valores (29,2), seguido de REC (21,6) e TFA (15,4) (p<0,05). Quanto ao número de reinserções, o sistema TFA foi o que necessitou do menor número de reinserções (p<0,05). Conclusão: Nas condições do estudo, pode-se concluir que o sistema ProDesign Duo Híbrido foi o mais durável; ainda que o sistema TF Adaptive tenha alcançado o comprimento de trabalho com maior facilidade

Objective: The present study compared three systems of thermally treated NiTi endodontic files regarding their achieved number of prepared root canals before fracture. Methods: Two hundred and ten slightly and moderately curved upper and lower molars with actual length ranging from 19 to 21 mm and apex foramens diameters up to 200 µm were used. The sample was allotted to three groups according to the instrumentation system in use: Reciproc (REC; R25), ProDesign Duo Hybrid (PDH; #25/.01 and #25/.08), and TF Adaptive (TFA; #25/.08). Five instruments/kits of each system were used. Then, it was registered the number of root canals prepared until the instrument fractured and the number of reinsertions needed until the working length was achieved. Results: The statistical analysis showed significant differences among the durability of the three systems, being the instruments of group PDH the ones that yielded higher reuses (29.2) followed by groups REC (21.6), and TFA (15.4) (P < .05). Regarding the number of insertions, the TFA system was the one that needed the lowest number of reinsertions (P < .05). Conclusion: Under this study conditions, ProDesign Duo Hybrid was the most durable system, whereas TF Adaptive system was the one that most easily achieved the working length.

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