Comparación de la microfiltración apical de cuatro tipos de cementos endodónticos: Endofill, mtaFillapex, Adseal y Roeko Seal / Comparison of the Apical Microleakage of Four Types Of Endodontic Cements: Endofill, mta Fillapex, Adseal and Roeko Seal / Comparação da microinfiltração apical de quatro tipos de cimentos endodônticos: Endofill, mta Fillapex, Adseal e Roeko seal

Introducción: La microfiltración apical es uno de los principales causantes de fracasos endodónticos donde hay invasión de bacterias y líquidos periapicales a la parte interna del conducto radicular y material de relleno. Materiales y Métodos: La muestra estuvo conformada por 60 dientes premolares unirradiculares que fueron seccionados en la unión amelocementaria, la instrumentación biomecánica se realizó con técnica rotatoria e irrigación con hipoclorito de sodio al 5.25% y EDTA 17%, se dividió aleatoriamente en 4 grupos (n=15) para cada tipo de cemento, la obturación se realizó con la técnica de condensación lateral, a nivel coronal se obturó con Ionómero vidrio base y resina, se colocaron en una incubadora a 37° sumergidos en NaCL 0.9% por 5 días hasta el fraguado de los cementos, para observar la microfiltración se utilizó el método filtración de tinta china y la diafanización con la técnica de Robertson. Las medidas de microfiltración apical se observaron utilizando el Estereomicroscopio. Resultados: El valor promedio fue menor para el cemento Adseal 0,33mm, seguido por los cementos Fillapex 0,87mm, Roeko seal 1,00mm y Endofill 1,30mm respectivamente. Hubo diferencias estadísticamente significativas en la microfiltración apical de los cuatro cementos endodónticos (p=0.00) Conclusiones: El cemento Adseal presentó menor microfiltración en comparación a los cementos Fillapex, Roeko seal y Endofill.

Introduction: Apical microleakage is one of the main causes of endodontic failure, either due to invasion of microorganisms or periapical fluids into the canal, and only the composition of the type of obturator cement favors its reduction. The objective of this research was to compare the apical microleakage of four types of endodontic cements Endofill, MTA Fillapex, Adseal and Roeko Seal. Materials and methods: The sample consisted of 60 single root premolar teeth that were sectioned at the cement- enamel junction, the biomechanical instrumentation was performed with a rotary technique and irrigation with sodium hypochlorite and edta, randomly divided into 4 groups (n = 15) for each type of cement, the obturation was performed with the lateral condensation technique, at the coronal level it was obturated with base glass ionomer and resin, they were placed in an incubator at 37° submerged in NaCL 0.9% for 5 days until setting. of the cements, to observe the microleakage the India ink filtration method was used and diaph-anization with the Robertson technique. Apical microleakage measurements were observed using the Stereomicroscope. Results: The average value was lower for the Adseal 0.33 mm cement, followed by the Fillapex 0.87 mm, Roeko Seal 1.00 mm and Endofill 1.30 mm cements respectively. There were sta-tistically significant differences in the apical microleakage of the four endodontic cements (p = 0.00) Conclusions: Adseal cement presented less microfiltration compared to Fillapex, Roeko Seal and Endofill cements

Introdução: a microinfiltração apical é uma das principais causas de falhas endodônticas onde há inva-são de microrganismos e líquidos periapicais ao interior do conducto e só a composição do tipo de cimento obturador favorece sua disminuição. O objetivo desta pesquisa foi comparar a microinfiltração apical de quatro tipos de cimentos endodônticos Endofill, MTA Fillapex, Adseal e Roeko Seal. Materiais e métodos: a amostra foi composta por 60 dentes pré-molares uniradiculares que foram seccionados na junção amelocementária. A instrumentação biomecânica foi realizada com técnica rotatória e irrigação com hipoclorito e edta, sendo dividida aleatoriamente em 4 grupos (n = 15) para cada tipo de cimento. A obturação foi realizada pela técnica de condensação lateral, no nível coronal foi obturado com base de ionômero de vidro e resina, foram colocados em incubadora a 37° submersos em NaCl 0,9% por 5 dias até a pega dos cimentos. Para observar a microfiltração utilizou-se o método de filtração em tinta nan-quim e diafanização pela técnica de Robertson. As medidas de microinfiltração apical foram observadas utilizando o estereomicroscópio. Resultados: o valor médio foi menor para o cimento Adseal (0,33 mm), seguido pelos cimentos Fillapex (0,87 mm), Roeko Seal (1,00 mm) e Endofill (1,30 mm), respectivamente. Houve diferenças estatisticamente significativas na microinfiltração apical dos quatro cimentos endo-dônticos (p = 0,00). Conclusões: o cimento Adseal apresentou menor microinfiltração comparado aos cimentos Fillapex, Roeko seal e Endofill.

Effect of sodium hypochlorite and calcium hypochlorite on the apical sealing ability of endodontic sealers

Aim: This study aimed to compare the influence of sodium hypochlorite (NaOCl) and calcium hypochlorite [Ca(OCl)2 ] on the apical sealing capacity of AH Plus (Dentsply Maillefer) and Bio-C Sealer (Angelus) endodontic sealers. Methods: Sixty permanent human lower incisors were randomly allocated (http://www.randomized.org), according to the irrigant used, into three groups (n=20): 0.9% sodium chloride (NaCl/Control); 2.5% NaOCl; and 2.5% Ca(OCl)2 . The root canal was prepared with rotary files under 10 mL of the solution corresponding to the experimental group. Each group was subdivided into two (n=10) according to the sealer used for filling: AH Plus (Dentsply Maillefer) or Bio-C Sealer (Angelus). Then, all samples were immersed in black India ink for one week. After the storage period, the roots were then grooved longitudinally and split, and the ink penetration was measured from the apical part to the coronal part of the root canal into which the ink penetrated using a stereomicroscope. Data were analyzed by one-way ANOVA and Tukey's post-hoc tests. Results: There was no statistical difference in ink penetration between the different endodontic sealers tested for the same irrigating solution (p > 0.05). However, when the Bio-C Sealer (Angelus) was used, the group treated with 2.5% Ca(OCl)2 was associated with lower values of apical leakage, compared to 2.5% NaOCl (p < 0.05). For the AH Plus sealer (Dentsply Maillefer), there was no difference between the irrigants (p > 0.05). Conclusions: Associating Ca(OCl)2 irrigant with Bio-C Sealer (Angelus) seems to be a good option to reduce apical leakage

Evaluation of Microleakage at the Junction Between Combined Amalgam/Composite Resin Restorations Using Different Bonding Systems in Class II Cavities

Abstract Objective: To evaluate the microleakage at the junction between amalgam-composite resin restorations using different bonding systems. Material and Methods: In this in-vitro study, standard class II cavities were prepared on 40 human maxillary premolars. The axial and gingival floor depths of the cavities were 2 mm and 1 mm below (cementoenamel junction), respectively. The samples were divided into 4 groups (n = 10). In all groups, a layer of 1-mm thick amalgam was used as a coating for the initial part of the gingival floor. In group 1, no bonding system was used for amalgam restoration. In group 2, G-Premio Bond was applied. G-Premio bond + alloy primer and single bond + alloy primer were used in group 3 and group 4, respectively. The rest of the cavities in all groups were then repaired using FiltekZ250 composite. The samples were thermocycled at 500 rpm and immersed in 1% methylene blue solution for 24 hours to allow dye penetration. Once cut, the samples were placed under a stereomicroscope (40X) to determine the microleakage rate. Data analysis was carried out using post-hoc and Chi-square tests (p<0.05). Results: The highest and lowest microleakage rate was related to groups 1 and 3, respectively. There was a significant difference between groups (1,2) and (1,3), and (1,4), and groups (2,3) (p<0.05). Conclusion: The use of alloy primer and bonding could reduce the microleakage between the two restorations (AU).

Influence of laser deproteinization of acid-etched dentin on marginal microleakage of class V composite restoration

Aim: Recent reports indicate that deproteinization of acid-etched dentin surface can extend penetration depth of adhesive agents. The main goal of the present research was to investigate the deproteinization effect of Nd:YAG and diode 940 lasers on acid-etched dentin and microleakage grade in class V composite restorations. Methods: 36 extracted human premolar teeth were selected to make standard buccal and lingual class V cavities. These samples were randomly split into three sub-groups: 1.Control group, in which composite was applied for restoration after etch and bonding process without deproteinization; 2.Nd:YAG laser group, in which the teeth were deproteinized with Nd:YAG laser after etching and painting internal surfaces of cavities with Van Geison stain and then composite restorations applied just as control group; 3.Diode laser group, in which the process was similar to Nd:YAG laser group, but instead, diode 940 laser was irradiated. The teeth were bisected into two equal longitudinal buccal and lingual halves. Marginal microleakage of samples was scored by using a stereomicroscope. Kruskal- Wallis, Mann-Whitney U and Fisher's statistical tests were employed for analysis of the obtained data. Results: A significant reduction in marginal microleakage was observed for both groups treated with laser (Nd:YAG and diode 940)compared to control (p=0.001 & p=0.047). There was no significant difference in marginal microleakage between Nd:YAG laser and diode 940groups (P = 0.333). Conclusion: Nd:YAG and diode 940 laser deproteinization of acid-etched dentin decreased the marginal microleakage of in-vitro class V resin composite restorations

Comparison of microleakage of an alkasite restorative material, a composite resin and a resin-modified glass ionomer

Aim: To compare the microleakage of Cention N, a subgroup of composite resins with a resin-modified glass ionomer (RMGI) and a composite resin. Methods: Class V cavities were prepared on the buccal and lingual surfaces of 46 extracted human molars. The teeth were randomly assigned to four groups. Group A: Tetric N-Bond etch-and-rinse adhesive and Tetric N-Ceram nanohybrid composite resin, group B: Cention N without adhesive, group C: Cention N with adhesive, and group D: Fuji II LC RMGI. The teeth were thermocycled between 5°-55°C (×10,000). The teeth were coated with two layers of nail vanish except for 1 mm around the restoration margins, and immersed in 2% methylene blue (37°C, 24 h) before buccolingual sectioning to evaluate dye penetration under a stereomicroscope (×20). The data were analyzed by the Kruskal-Wallis and Wilcoxon tests (α=0.05). Results: Type of material and restoration margin had significant effects on the microleakage (p<0.05). Dentin margins showed a higher leakage score in all groups. Cention N and RMGI groups showed significant differences at the enamel margin (p=0.025, p=0.011), and for the latter group the scores were higher. No significant difference was found at the dentin margins between the materials except between Cention N with adhesive and RMGI (p=0.031). Conclusion: Microleakage was evident in all three restorative materials. Cention N groups showed similar microleakage scores to the composite resin and displayed lower microleakage scores compared with RMGI

Comparison of results from two different leakage models to evaluate the apical sealing of endodontic materials

Introduction: The methods used to evaluate the apical sealing of root canal filling materials have some limitations and great variability of results can be observed. Aim: The aim of this study was to compare, in an ex vivo apexification model, the results from bacterial and glucose leakage tests, which were applied in mineral trioxide aggregate (MTA) apical plugs. Materials and Methods: Sixty root segments (12mm) were randomly divided into 2 experimental groups (n=30): G1) MTA; G2) MTA + phosphate-buffered saline intracanal. Half of the specimens in each group were submitted to bacterial leakage test with E. faecalis for 70 days. The other half was submitted to the glucose leakage test under pressure (103KPa) for 60 min. The results from the two tests were compared based on the number of specimens presenting leakage. Data were analyzed by Fisher's test (p < 0.05). Results: There was no significant difference between tests for both groups analyzed (p > 0.05).Conclusion: The results of the present ex vivo study demonstrated that there was no difference between glucose and bacteria leakage evaluation methods, within the parameters of the present study and regardless

Microfiltración marginal de resinas de relleno masivo y nanohíbrida en molares deciduos / Marginal microleakage of bulk fill and nanohybrid resins in deciduous teeth

Introducción: En la atención odontológica a niños es crucial seleccionar materiales restaurativos con buen rendimiento clínico y corto tiempo de aplicación, especialmente en pacientes con capacidad de atención limitada. Las resinas compuestas, con el mejoramiento de sus propiedades físicas y mecánicas, constituyen hoy uno de los materiales de mayor elección por el odontopediatra. Las resinas de relleno masivo son una alternativa atractiva para las restauraciones en el sector posterior. Objetivo: Comparar el grado de microfiltración marginal de resinas de relleno masivo y nanohíbrida en molares deciduos. Métodos: Estudio experimental, in vitro, en cuarenta molares deciduos; exodonciados por motivos terapéuticos, divididos en dos grupos. Grupo I: resina nanohíbrida con técnica incremental (Tetric® N Ceram - Ivoclar Vivadent) y Grupo II: resina de relleno masivo con técnica monoincremental (Tetric® N Ceram bulk fill - Ivoclar Vivadent). Se realizó un proceso de termociclado manual de 500 ciclos, entre 5 ºC ± 2 ºC y 55 ºC ± 2 ºC. Las muestras fueron sumergidas en azul de metileno al 0,5 por ciento durante 24 horas a 37 ºC. Se analizaron con el microscopio estereoscópico de luz a 40X. Resultados: Todas las muestras presentaron microfiltración. Con el uso de resina nanohíbrida, el 25 presentó microfiltración leve; el 30 por ciento, moderada; y el 45 por ciento, severa. En el grupo de la resina de relleno masivo, el 30 por ciento presentó microfiltración leve; el 35 por ciento, moderada; y el 35 por ciento, severa. No se encontró diferencia significativa entre ambos grupos (p = 0,55). Conclusiones: Ambas resinas, de relleno masivo y nanohíbrida, presentaron similar microfiltración marginal in vitro, en molares deciduos; por lo que la técnica de relleno masivo, por su fácil y rápida aplicación en un solo tiempo, es una buena alternativa en la rehabilitación dental odontopediátrica(AU)

Introduction: In children's dental care it is crucial to select restorative materials of proven clinical quality and a short application period, particularly with patients of limited attention capacity. Due to their improved physical and mechanical properties, composite resins are currently one of the materials of choice for children's dental care. Bulk fill resins are an attractive alternative for posterior restorations. Objective: Compare the degree of marginal microleakage of bulk fill and nanohybrid resins in deciduous teeth. Methods: An experimental in vitro study was conducted of 40 deciduous teeth extracted for therapeutic reasons, which were divided into two groups. Group I: nanohybrid resin by incremental technique (Tetric® N Ceram - Ivoclar Vivadent) and Group II: bulk fill resin by monoincremental technique (Tetric® N Ceram bulk fill - Ivoclar Vivadent). A manual 500-cycle thermocycling procedure was performed at 5ºC ± 2ºC to 55ºC ± 2ºC. The samples were soaked in 0.5 percent methylene blue at 37ºC for 24 hours and analyzed under a light stereo microscope at 40X. Results: Microleakage was present in all the samples. In the nanohybrid resin group, microleakage was mild in 25 percent, moderate in 30 percent and severe in 45 percent. In the bulk fill resin group, microleakage was mild in 30 percent, moderate in 35 percent and severe in 35 percent. No significant difference was found between the groups (p = 0.55). Conclusions: Both resins, bulk fill and nanohybrid, presented similar in vitro marginal microleakage in deciduous molars. The bulk fill technique is therefore a good alternative for children's dental rehabilitation, due to its easy and fast application in a single session(AU)

Estudio comparativo in vitro de la filtración apical con tres técnicas de obturación / Estudo comparativo in vitro de filtração apical com três técnicas de obturação / A comparative in vitro study of apical leakage with three obturation techniques

Resumen Objetivo: Comparar la microfiltración apical de dientes obturados con tres diferentes técnicas: condensación lateral, condensación vertical y sistema obtura II in vitro. Métodos: Se utilizaron 75 dientes uniradiculares, divididos en 5 grupos, Grupo 1: condensación lateral, Grupo 2: condensación vertical, Grupo 3: sistema obtura II, Grupo 4: control positivo, Grupo 5: control negativo. Las raíces fueron sometidas a filtración apical por difusión indirecta con tinta china, diafanizadas y observadas con un microscopio Vasconcellos. Se realizaron pruebas estadístico descriptivo con el programa GraphPad prism 8. Resultados: El grupo 1 presentó mayor filtración (0,6603±0,5063) con una diferencia estadísticamente significativa en comparación al grupo 3 (p<0.05), sin embargo, no hubo extrusión de la gutapercha a diferencia de los otros dos grupos. Conclusiones: La técnica de sistema Obtura II presentó un mejor sellado apical, lo que condujo a una disminución en la filtración apical, demostrando ser más efectiva en comparación a las otras técnicas utilizada en el estudio.

Resumo Objetivo: Comparar a microfiltração apical de dentes obturados com três diferentes técnicas: condensação lateral, condensação vertical e sistema obtura II. Métodos: foram utilizados 75 dentes unirradiculares, divididos em 5 grupos, Grupo 1: condensação lateral, Grupo 2: condensação vertical, Grupo 3: sistema obtura II, Grupo 4: controle positivo, Grupo 5: controle negativo. As raízes foram submetidas à filtração apical por difusão indireta com tinta da Índia, diafanizadas e observadas ao microscópio Vasconcellos. Os testes estatísticos descritivos foram realizados com o programa GraphPad prism 8. Resultados: O Grupo 1 apresentou maior filtração (0,6603 ± 0,5063) com diferença estatisticamente significante em relação ao Grupo 3 (p <0,05), porém não houve extrusão de guta-percha ao contrário dos outros grupos onde havia. Conclusões: A técnica do sistema Obtura II apresentou melhor selamento apical, o que levou à diminuição da filtração apical, mostrando-se mais eficaz em relação às outras técnicas utilizadas no estudo.

Abstract Objective: To compare the in vitro apical microleakage of teeth sealed with three techniques: lateral condensation, vertical condensation, and Obtura II. Methods: A total of 75 single-root teeth were divided into five groups: Group 1 - lateral condensation, Group 2 - vertical condensation, Group 3 - Obtura II system, Group 4 - positive control, Group 5 - negative control. The roots were subjected to apical leakage through indirect diffusion with Chinese ink, diaphonized, and observed under a Vasconcellos microscope. Descriptive statistical tests were conducted with GraphPad Prism 8. Results: Group 1 showed greater microleakage (0.6603 ± 0.5063) with a statistically significant difference compared to group 3 (p < 0.05). However, there was no gutta-percha extrusion, unlike in the other groups. Conclusion: The Obtura II technique showed better sealing, which led to decreased apical microleakage, thus proving to be more effective than the other techniques studied.

Avaliação do cimento resinoso autoadesivo como tampão cervical para clareamento interno / Evaluation of a self-adhesive resin cement as a cervical barrier in intracoronal bleaching

Objetivo: Avaliar capacidade seladora de um cimento resinoso autoadesivo como tampão cervical para clareamento interno. Métodos: Quarenta incisivos inferiores bovinos recém-extraídos foram tratados endodonticamente. Após 72 horas, foi realizada a desobturação parcial do canal radicular para confecção de tampão cervical dividido em quatro grupos aleatório (n = 40), cada um contento dez amostras (n = 10), com os seguintes materiais: cimento resinoso autoadesivo, cimento resinoso adesivo, cimento de óxido de zinco sem eugenol com presa por água e cimento de ionômero de vidro quimicamente ativado (grupo controle). Após 24 horas de presa dos materiais, os elementos dentais foram submetidos ao clareamento interno com perborato de sódio misturado com água destilada pelo período de 7 dias em câmara umidificadora a 37 ºC. Posteriormente, o material clareador foi removido e um corante (fucsina básica 0,5%) foi colocado no interior da câmara pulpar, sendo renovado de 8 em 8 horas, pelo período de 24 horas. Os elementos dentais foram seccionados no sentido longitudinal em máquina de corte para avaliação quantitativa em um microscópio óptico sob aumento de 20x. O grau de penetração do corante foi analisado ao longo do tampão cervical (topo até base). Resultados: Não houve diferença significativa entre os materiais tamponantes utilizados (p = 0,5997). Conclusão: O cimento resinoso autoadesivo apresentou baixo grau de infiltração, sendo uma opção de material alternativo com finalidade de tampão cervical.

Aim: To evaluate the sealing ability of a self-adhesive resin cement as a cervical barrier for internal bleaching. Methods: Forty recently extracted bovine lower incisors were endodontically treated. After 72 hours, partial disobturation of the root canal was performed, a cervical barrier was placed, and the teeth were divided into four random groups (n = 40), each containing ten samples (n = 10), using the following materials: self-adhesive resin cement, adhesive resin cement, zinc oxide cement without eugenol cured by water, and chemically activate glass ionomer cement (control group). Twenty-four hours after the materials were cured, the teeth were subjected to internal bleaching with sodium perborate and distilled water for a period of seven days in a humidified chamber at 37°C. After, the bleaching material was removed and a dye (0.5% basic fuchsin) was placed inside the pulp chamber and renewed every eight hours for a period of 24 hours. The teeth were sectioned longitudinally in a cutting machine for quantitative evaluation using an optical microscope under 20x magnification. The degree of dye penetration was evaluated through the cervical barrier (top to bottom). Results: No significant difference was observed among the cervical barrier materials used in this study (p = 0.5997). Conclusion: The self-adhesive resin cement had low degree of leakage and represents an alternative material option to be used as a cervical barrier.

Microfiltración coronal según materiales de restauración temporal empleados en endodoncia / Coronal microleakage according to the temporary restorative materials used in endodontic treatment

RESUMEN Introducción: La microfiltración coronal causada por los materiales de restauración temporal es considerada una de las causas del fracaso de los tratamientos endodónticos. A raíz de ello, en los últimos años se ha buscado crear un material de restauración temporal que sea capaz de evitar este problema. Objetivo: Comparar in vitro la microfiltración coronal de un cemento experimental y cuatro materiales de restauración temporal usados en endodoncia. Métodos: Se realizaron cavidades clase I en 90 premolares, divididos en 10 grupos (n= 9) y evaluados en dos periodos de tiempo (1 y 2 semanas). Se realizó la elaboración del cemento experimental, posteriormente se llevó a cabo el sellado coronal de las piezas dentales con el cemento experimental, Clip F (VOCO), Eugenato (MOYCO), Ketac™ Molar Easymix 3M (ESPE) y Coltosol® F. Los especímenes fueron sumergidos en tinta china (Pelikan) durante 1 y 2 semanas. Se evaluó la microfiltración en la interfase pared dentinaria-restauración temporal utilizando un esteromicroscopio (Leica Microsystems LAS EZ versión 2.0.0). La medición se realizó en milímetros en el programa LAS EZ versión 2.0.0. Resultados: Se encontró diferencias estadísticamente significativas (p < 0,05) al comparar la microfiltración coronal de los cinco materiales de restauración temporal, según el tiempo de exposición en tinta (1 y 2 semanas). Conclusiones: El cemento experimental presentó menor microfiltración que el Coltosol® F y Ketac™ Molar EasyMix 3M (ESPE); sin embargo, ninguno de los cuatro materiales fue capaz de prevenir la microfiltración en su totalidad(AU)

ABSTRACT Introduction: Coronal microleakage caused by temporary restorative materials is viewed as one of the reasons for endodontic failure. Efforts have been made in recent years to create a temporary restorative material capable of preventing that problem. Objective: Compare in vitro coronal microleakage of an "experimental cement" and four temporary restorative materials used in endodontics. Methods: Class I cavities were made in 90 premolar teeth divided into 10 groups (n= 9) and evaluated at two time periods (1 and 2 weeks). The "experimental cement" was prepared and then coronal sealing of the teeth was performed with the experimental Cement, F (VOCO), Eugenato (MOYCO), Ketac™ Molar Easymix 3M (ESPE) and Coltosol® F. The pieces were submerged in India ink (Pelikan)for 1 and 2 weeks. Microleakage was evaluated on the interface dentin wall / temporary restoration using a stereo microscope (Leica Microsystems LAS EZ version 2.0.0). Measurement was made in millimeters using the software LAS EZ version 2.0.0. Results: Statistically significant differences were found (p < 0.05) when comparing coronal microleakage in the five temporary restorative materials according to exposure time in ink (1 and 2 weeks). Conclusions: The experimental cement had less microleakage than Coltosol® F and Ketac™ Molar EasyMix 3M (ESPE). However, none of the four materials was capable of completely preventing microleakage(AU)

Adaptación de pilares rectos sobre implantes con conexión hexagonal interna y externa por microscopía electrónica de barrido / Adaptation of straight pillars on implants with internal and external hexagonal connection by scanning electronic mi-croscopy / Adaptação de pilares retos em implantes com conexão hexagonal interna e externa por microscopia eletrônica de varredura

En implantología oral, ha sido motivo de investigación y constante evolución la interfase implante-pilar, princi-palmente desde el punto de vista biomecánico y biológico. Objetivo: Valorar el espacio o "gap" en la interfase implante-pilar en implantes de conexión hexagonal interna y externa por medio de microscopía electrónica de barrido (MEB). Materiales y Métodos: Estudio in vitro en 24 implantes (Bionnovation®) divididos en dos gru-pos (n=12): conexión hexagonal interna y externa. Para el experimento, se atornillaron pilares rectos con 30N de torque. A su vez 6 implantes por grupo se sometieron a 500000 ciclos de carga dinámica; posteriormente, se evaluó por MEB el espacio de la interfase implante pilar en 3 puntos de todas las muestras, las medias de los resultados de cada espécimen se respaldaron en tablas de Excel y se analizaron en el programa BioEstat 5.3. Resultados: Mediante test T para muestras independientes, con una significancia del 95%, se encontró una diferencia muy significativa luego de la aplicación de la carga dinámica en los implantes de hexágono ex-terno (p= 0.0002). En los implantes de hexágono interno también existió diferencia estadística (p= 0.03). Entre los implantes de hexágono externo e interno existieron diferencias muy significativas en la precisión del ajuste en la interfase implante pilar antes y después de la aplicación de las cargas dinámicas (p= <0.0001 y p= 0.0003 respectivamente). Conclusiones: Las cargas dinámicas aumentaron significativamente la discrepan-cia en la conexión implante-pilar de los implantes de hexágono externo e interno (p= < 0.05); adicionalmente, la distancia del "gap" fue mayor para los implantes de hexágono externo en contraste con los implantes de Hexágono Interno antes y después de la carga dinámica, siendo muy significativo (p= < 0.0003).

In oral implantology, the implant-pillar interface has been a subject of research and constant evolution, mainly from the biomechanical and biological point of view. Objective: To assess the gap in the implant-abutment interface in internal and external hexagonal connection implants by means of scanning electron microscopy (SEM). Materials and Methods: In vitro study in 24 implants (Bionnovation®) divided into two groups (n = 12): internal and external hexagonal connection. For the experiment, straight pillars with 30N of torque were screwed. In turn, 6 implants per group underwent 500,000 cycles of dynamic loading; Subsequently, the space of the pillar implant interface at 3 points of all samples was evaluated by MEB, the means of the results of each specimen were supported in Excel tables and analyzed in the BioEstat 5.3 program. Results: Using a T test for independent samples, with a significance of 95%, a very significant difference was found after the application of the dynamic load in the external hexagon implants (p = 0.0002). In the internal hexagon implants there was also a statistical difference (p = 0.03). Between the external and internal hexagon implants there were very significant differences in the accuracy of the adjustment in the abutment implant interface before and after the application of the dynamic loads (p = <0.0001 and p = 0.0003 respectively). Conclusions: Dynamic loads significantly increased the discrepancy in the implant-abutment connection of the external and internal hexa-gon implants (p = <0.05); additionally, the gap distance was greater for external hexagon implants in contrast to Internal Hexagon implants before and after dynamic loading, being very significant (p = <0.0003).

Na implantologia oral, a interface implante-pilar tem sido objeto de pesquisa e evolução constante, principal-mente do ponto de vista biomecânico e biológico. Objetivo: Avaliar o espaço ou "gap" na interface implan-te-pilar em implantes de conexão hexagonal interna e externa por meio de microscopia eletrônica de varre-dura (MEV). Materiais e Métodos: Estudo in vitro em 24 implantes (Bionnovation®) divididos em dois grupos (n = 12): conexão hexagonal interna e externa. Para o experimento, pilares retos com 30N de torque foram parafusados. Por sua vez, 6 implantes por grupo passaram por 500.000 ciclos de carregamento dinâmico; posteriormente, o espaço da interface do implante de pilar em 3 pontos de todas as amostras foi avaliado pelo MEV, as médias dos resultados de cada amostra foram suportadas em tabelas Excel e analisadas no programa BioEstat 5.3. Resultados: Usando um teste T para amostras independentes, com significância de 95%, foi encontrada uma diferença muito significativa após a aplicação da carga dinâmica nos implantes hexagonais externos (p = 0,0002). Nos implantes hexagonais internos também houve diferença estatística (p = 0,03). Entre os implantes hexágono externo e interno, houve diferenças muito significativas na precisão do ajuste na interface do implante de pilar antes e após a aplicação das cargas dinâmicas (p = <0,0001 ep = 0,0003, respectivamente). Conclusões: As cargas dinâmicas aumentaram significativamente a discrepância na conexão implante-pilar dos implantes hexágono externo e interno (p = <0,05); além disso, a distância do gap foi maior para os implantes hexagonais externos, em contraste com os implantes de hexágono interno antes e após o carregamento dinâmico, sendo muito significativa (p = <0,0003).

Universal adhesives and dual-cured core buildup composite material: adhesive properties

Abstract Dual-cured buildup composites and simplified light-cured adhesive systems are mixed with a chemical activator to prevent the incompatibility between them. Objective: To evaluate microshear bond strength (μSBS) and nanoleakage (NL) of three universal adhesives used under buildup composites using different curing modes, at baseline and after 6-months (6m). Methodology: Dentin specimens of 55 molars were assigned to: Clearfil Universal Bond[CFU], Prime&Bond Elect[PBE] and One Coat 7 Universal[OCU]. All-Bond Universal[ABU] and Adper Scotchbond Multi-Purpose[SMP] were used as controls. CFU, PBE, and OCU were: light-cured [LC], dual-cured using a self-curing activator [DC], and self-cured, using a self-curing activator and waiting for 20 min [SC]. Upon the application of the adhesive, transparent matrices were filled with a dual-cured buildup composite and light cured, then tested in mSBS. For NL, the specimens were submersed in ammoniacal silver nitrate and sectioned to observe under the SEM. Three-way ANOVA and Tukey's test were applied (α=0.05). Results: OCU/LC-PBE/LC resulted in higher mean μSBS than ABU/LC. For SMP/DC higher mean μSBS were obtained than for both CFU/DC and OCU/DC (baseline). No universal adhesive was significantly affected by curing mode or storage time. CFU, PBE, and OCU did not undergo significant changes in any curing mode (p>0.05). NL (baseline) PBE/LC resulted in higher %NL compared to ABU/LC. SMP/DC resulted in higher %NL than CFU/DC-OCU/DC. CFU/LC/DC resulted in lower %NL than CFU/SC. PBE/SC resulted in lower %NL than PBE/DC. OCU/LC/SC showed lower %NL than OCU/DC. OCU showed significant lower %NL than CFU and PBE. All CFU groups, as well as OCU/SC, resulted in increased %NL at 6m when compared with baseline. Conclusion: For universal adhesives used in etch-and-rinse mode, self-cured activator and different curing modes did not influence μSBS. However, some interactions were observed for NL, but this influence was material-specific.

Sealing Carious Fissures with Resin Infiltrant in Association with a Flowable Composite Reduces Immediate Microleakage?

Abstract Objective: To compare the immediate microleakage of carious fissures sealed with a caries infiltrant covered by a flowable composite or solely with a flowable composite. Material and Methods: Extracted carious molars (n=20) were selected and paired among the experimental groups according to caries progression scores. Experimental groups (n=10) were divided according to the following sealing techniques: 1) caries infiltrant (Icon) + flowable composite (Z350 flow); 2) flowable composite (Z350 flow). Specimens were immersed in 3% methylene blue and evaluated in a stereomicroscope. Microleakage scores were attributed independently by two calibrated evaluators and the mode value was considered as the mean for the specimen. Binomial tests were used to test differences between two independent sample proportions at 5% significance level. Results: In the flowable composite group, a higher prevalence of dye penetration along the full depth of the fissure was observed, compared with caries infiltrant + flowable composite (p<0.05). For specimens showing dye penetration up to half of the fissure, in caries infiltrant + flowable composite group, all specimens showed dye penetration into the sealant, but not over the infiltrant. Conclusion: Using caries infiltrant as sealing material under a flowable composite cover is effective to improve the immediate sealing ability in carious fissures compared to sealing with flowable composite.

Effect of a Resin Coating Material on the Microleakage of Class V Restorations With or Without Post-Operative Bleaching

Abstract Objective: To evaluate the effect of a resin coating material on the microleakage of Class V composite resin restorations with and without post-operative bleaching. Material and Methods: Eighty class V cavities (3×3×1.5 mm) were prepared and filled with Z250 XT composite resin in the buccal and lingual surfaces of 40 sound human molars. Then the samples were randomly divided into 4 groups (n=20) and treated as follows: Group A: applying a resin coating (G-Coat Plus) on the restoration, then bleaching with 40% hydrogen peroxide; Group B: Post-Operative bleaching without prior use of resin coating; Group C: applying resin coating agent, and no further bleaching; and Group D: no resin coating, no bleaching. The specimens were thermocycled and immersed in 1% methylene blue for 24 hours, then cut into sections bucco-lingually. The samples were scored regarding the amount of dye penetration under a stereomicroscope (x20). Data were analyzed with Chi-squared and Fisher exact tests (p<0.05). Results: The maximum gingival and occlusal microleakage was detected in group B, while the minimum was seen in group C. In all the groups, microleakage at gingival margins was higher than occlusal margins (p<0.001). Conclusion: Application of a resin coating is an effective method in reducing microleakage of the restorations before and after bleaching.

The Use of Resinous Infiltrants for the Management of Incipient Carious Lesions: a Literature Review / Uso de Infiltrantes Resinosos para Tratamento de Lesões Cariosas Incipientes: uma Revisão da Literatura

The objective of this work was to analyze scientific evidence from a literature review pertaining to the effectiveness of resinous infiltrants for minimally invasive treatment of incipient carious lesions. Studies published between 2002 and 2019 were queried from the following databases: Capes, PubMed, Medline, BBO, Lilacs and SciELO. The search keywords included "Dental Caries", "Tooth Remineralization", "Dental Leakage". Most of the studies found resin-infiltrating treatment to be a viable option for the minimally invasive treatment of incipient carious lesions; this treatment was able to fulfill the primary expected effects: inhibition of carious progression and the lesions esthetic improvement. However, some issues need to be clarified to improve the safety of this treatment because it can be recommended in clinical practice. Inconclusion, the use of resinous infiltrants has been reported as promising for the treatment of incipient carious lesions. However, there is a need for long-term studies to confirm the effectiveness of this treatment to determine its applicability for clinical use. (AU)

O objetivo desse trabalho foi analisar evidências científicas, por meio de uma revisão de literatura, sobre a eficácia do uso de infiltrantes resinosos para o tratamento minimamente invasivo de lesões cariosas incipientes. A seleção do material literário utilizado foi realizada por pesquisa sobre o tema nas bases de dados: portal de periódicos Capes, PubMed, Medline, BBO, Lilacs e SciELO, abrangendo prioritariamente, o período de 2002 a 2019. Para busca nas bases de dados foram utilizadas palavras-chave como "Cárie Dentária", "Remineralização Dentária", "Infiltração Dentária", assim como suas correspondentes na língua inglesa. A maioria dos estudos encontrados aponta o tratamento infiltrante resinoso como uma opção viável para o tratamento minimamente invasivo de lesões cariosas incipien tes sendo capaz de cumprir os principais efeitos esperados: inibição da progressão cariosa e melhoria estética das lesões. Entretanto, alguns impasses necessitam ser esclarecidos para que o tratamento seja recomendado com mais segurança na prática clínica. Conclui-se que o uso de infiltrantes resinosos tem sido relatado como promissor para o tratamento de lesões cariosas incipientes, contudo há necessidade de novas pesquisas e estudos a longo prazo para confirmar sua eficácia em todos aspectos desejáveis para seu uso clínico. (AU)

A perspective of marginal microleakage in class II composite resin restorations using different types and techniques: an in-vitro study / Una perspectiva de la microfiltración marginal en restauraciones de resina compuesta de clase II usando diferentes tipos y técnicas: un estudio in-vitro

The study aimed to introduce a perspective of the essential reason behind why marginal microleakage develops regardless of the composite type, the technique, or the bonding system applied, especially in gingival floor of class II cavities. Materials and Methods: Three types of composite resin materials (CharmfilTM, ParaFillTM, and ProMedica®) were used to evaluate microleakage of class II restorations using two restorative approaches. Twenty four newly extracted bicuspid teeth were divided into two main groups (n=12 each) according to the restoration technique (open or closed sandwich techniques). Teeth of each group were then divided into 3 groups (n= 4 each) according to the type of the composite resin used. The restorations were then subjected to a thermocycling process and then were immersed into methylene blue solution for 12 hours. Mesiodistal sectional cuts were made along the central grooves and assessed under stereomicroscope for marginal microleakage. The data were statistically analyzed with a p-value <0.05 considered significant. Results: There were no statistically significant differences in marginal microleakage between the three examined groups using both techniques (p>0.05). Under the microscope, the marginal microleakage was more obvious at the cervical region than at the occlusal region. Conclusion: There was no effect of the composite type or the application technique used on the occurrence of marginal microleakage. The first portion of the material applied against the cavity floor is the primary factor involved in possibly minimizing marginal microleakage.

El estudio tuvo como objetivo presentar una perspectiva de la razón esencial por la cual se desarrolla microfiltraciones independientemente del tipo de resina compuesta, el sistema de unión aplicado, especialmente en el piso gingival de cavidades de clase II. Materiales y Métodos: Se utilizaron tres tipos de resina compuesta (CharmfilTM, ParaFillTM y ProMedica®) para evaluar la microfiltración de restauraciones de clase II utilizando dos enfoques restaurativos. Veinticuatro dientes bicúspides recién extraídos se dividieron en dos grupos (n=12 cada uno) de acuerdo con la técnica de restauración (técnicas de sándwich abierto o cerrado). Los dientes de cada grupo se dividieron en 3 sub-grupos (n=4 cada uno) de acuerdo con el tipo de resina compuesta utilizada. Las restauraciones se sometieron después a un proceso de termociclado y finalmente se sumergieron en una solución de azul de metileno durante 12 horas. Se realizaron cortes en la sección mesiodistal a lo largo de los surcos centrales y se evaluaron bajo lupa para determinar la ocurrencia de microfiltración marginal. Los datos se analizaron estadísticamente con un valor de p<0,05 considerado significativo. Resultados: No hubo diferencias estadísticamente significativas en la microfiltración marginal entre los tres grupos examinados utilizando ambas técnicas (p>0.05). Bajo la lupa la microfiltración marginal fue más obvia en la región cervical que en la región oclusal. Conclusión: No hubo efecto del tipo compuesto o la técnica de aplicación utilizada en la aparición de microfiltración marginal. La primera porción del material aplicado el piso de la cavidad es el factor principal involucrado en la posibilidad de minimizar la microfiltración marginal.

Influence of Cavity Dimensions on Microleakage of Two Bulk-Fill Composite Resins

Objective: To evaluate the effect of cavity dimensions on the amount of microleakage in two different types of bulk-fill composite resins. Material and Methods: Forty class II cavities were prepared in the mesial and distal surfaces of human molars without any carious lesions. The samples were divided into 4 groups (n=10): Group 1: cavities with 3 mm of buccolingual width (known as the smaller cavity), filled with Tetric N-Ceram Bulk Fill composite resin; Group 2: cavities with 6 mm of buccolingual width (larger cavity), filled with Tetric N-Ceram Bulk Fill composite resin; Group 3: cavities with 3 mm of buccolingual width, filled with X-Tra Base composite resin; and Group 4: cavities with 6 mm of buccolingual width, filled with X-Tra Base composite. After the specimens were thermocycled for 500 cycles at 5/55°C, they were immersed in 1% methylene blue for 24 hours, and then cut into sections mesiodistally in the longitudinal axis of each tooth. Then, the samples were scored regarding the amount of dye penetration in two occlusal and gingival areas under a stereomicroscope (x32). Data was submitted to Kruskal- Wallis and Mann-Whitney tests. Results: The highest degrees of microleakage in larger cavities filled with X-Tra Base among the four groups. There was a significant statistic difference (p=0.012) between large and small cavities filled with X-Tra Base (Groups 3 and 4); however, there was no significant difference between the two cavity sizes of Tetric N-Ceram Bulk-filled groups. Conclusion: Microleakage of composite resins depends on the dimension of the cavity and the type of composite resin used.

Development and characterization of a novel bulk-fill elastomeric temporary restorative composite

Abstract Objectives: This study investigated the physical and mechanical properties, antibacterial effect and biocompatibility of novel elastomeric temporary resin-based filling materials (TFMs) containing zinc methacrylate (ZM). Material and Methods: Experimental TFMs were prepared by mixing the zinc methacrylate with monomer, co-monomer, photoinitiator and fillers. A ZM concentration of 0 (control), 0.5% (Z0.5); 1% (Z1), 2% (Z2), or 5% (ZM5) wt% was added to the TFMs. Fermit-N (F) was used for comparison with the experimental material. Microleakage, water sorption/solubility, degree of conversion, depth of cure, ultimate tensile strength, and hardness were determined and compared. A modified direct contact test (DCT) with Enterococcus faecalis and a Streptococcus mutans' biofilm accumulation assay was carried out to evaluate the antimicrobial effect and cytotoxicity of the assay. Statistical comparisons were performed (α=5%). Results: The results showed that the physical and mechanical properties of the experimental TFMs with ZM are comparable with the properties of the commercial reference and some properties were improved, such as lower microleakage and water sorption, and higher ultimate tensile strength values. TFMs with ZM killed E. faecalis only after 1 h. Biofilm development of S. mutans was not affected by the inclusion of ZM in the experimental TFMs. Conclusions: The present findings suggest that the physical, mechanical and biological properties of the experimental TFMs with ZM are comparable with the properties of the commercial reference. However, some properties were improved, such as lower microleakage and water sorption, and higher ultimate tensile strength values.

Potencial antimicrobiano de diferentes retentores intrarradiculares frente a Enterococcus faecalis: uma avaliação in vitro / Evaluation of antibacterial activity of different intraradicular retainers against Enterococcus faecalis: in vitro evaluation

Resumo Introdução O tratamento endodôntico tem como objetivo erradicar microrganismos bacterianos e fúngicos do canal radicular, ou pelo menos possibilitar sua redução para níveis compatíveis com a saúde do tecido perirradicular, uma vez que, após o tratamento endodôntico, colônias de microrganismos residuais podem estar presentes nos túbulos dentinários e no cemento. Objetivo Avaliar o potencial antimicrobiano de diferentes tipos de retentores intrarradicularess em dentes bovinos. Material e método 50 dentes unirradiculares após tratamento endodôntico concluído foram desobturados, bem como tiveram seus condutos preparados para a cimentação dos retentores intrarradiculares. Posteriormente, os dentes foram contaminados por Enterococcus faecalis por meio da montagem de um dispositivo, o qual permitiu a infiltração bacteriana. Os dados resultantes da contagem das Unidades Formadoras de Colônia foram analisados utilizando o teste de ANOVA one-way, seguido pela análise de comparações múltiplas de Tukey. Resultado Decorrido o período de 14 dias, o grupo que apresentou a maior infiltração bacteriana foi o grupo-controle, o qual não continha nenhum tipo de retentor intrarradicular, seguido do G1-FV (grupo de continha retentor radicular de fibra de vidro) e G2-FC (grupo de que continha retentores radiculares de fibra de carbono). O menor grau de recuperação bacteriana foi encontrado nos grupos G3-Ni-Cr e G4-Cu-Al, os quais continham retentores intrarradiculares metálicos formados por ligas de níquel-cromo e cobre-alumínio, respectivamente. Conclusão Os retentores aqui avaliados apresentam diferentes efeitos antimicrobianos. Assim, a utilização de um pino com melhores resultados antimicrobianos favorece maiores chances de sucesso nos tratamentos reabilitadores.

Abstract Introduction The ultimate goal of endodontic treatment is the eradication of microorganism from the root canal space, or at least their reduction to levels compatible with periradicular tissue health since after endodontic treatment colonies of residual microorganisms may be present in the dentinal tubules and cementum. Objective To evaluate the antibacterial activity of different fiber posts in the root canal system of bovine teeth. Material and method Here, 90 uniradicular bovine teeth were randomly assigned after complete endodontic therapy. The samples were unthreaded, as well as had their conduits prepared for the cementation of the intracanal retainers. Subsequently, the teeth were exposed to Enterococcus faecalis by means of the assembly of a device, which allowed bacterial infiltration. The data of the amount by colony forming unit (CFU) per ml assay were analyzed by one-way ANOVA followed by Tukey's HSD post hoc test (p<0,05). Result After the 14-day period, the group that presented the highest bacterial infiltration was the control group, which did not contain any type of intrarradicular retainer, followed by G1-FV (group of contained fiber glass post) and G2- FC (group containing carbon fiber reinforced post). Results of the smallest degree of bacterial recovery was found in the G3-Ni-Cr and G4-Cu-Al groups, which contained metallic intracanal retainers by nickel-chromium and copper-aluminum alloys respectively. Conclusion The intracanal retainers evaluated here presented different antimicrobial effects. Thus, the use of intracanal post with better antimicrobial results, favors greater chances of success in rehabilitation treatments.

Effects of primer excess on marginal adaptation, nanoleakage and bond strength of adhesive systems after aging

There is no consensus about the amount of primer inserted into the cavity. Aim: This study aimed to evaluate the effects of the amount of primer used on dentin microtensile bond strength (µTBs), nanoleakage and marginal sealing, following thermomechanical aging. Methods: 48 human third molars were selected and a box-shaped class I cavity was constructed to maintain enamel margins. Teeth were randomly assigned to 6 experimental groups (n=8). For the bonding protocols of the restorative procedure, two adhesive systems were used: three-step etch-and-rinse and two-step self-etch. Epoxy resin replicas of the occlusal surface were made, and the specimens were submitted to thermomechanical aging. Newer replicas were obtained after thermomechanical aging, and marginal adaptation was observed using SEM. To obtain sections (0.7 x 0.7 mm) for testing at a tension of 0.5 mm/min, teeth were serially sectioned in the buccallingual direction, parallel to the occlusal surface. Failure mode was then obtained. For nanoleakage evaluation, one section of each tooth was immersed in AgNO3 and evaluated using SEM. The µTBs data were submitted to a two-way ANOVA and Tukey's test (α= 0.05) Results: One drop of primer promoted higher µTBs than two or three drops. Besides, the three-step etch-and-rinse promoted greater µTBs (19.78) than the two-step self-etch adhesive (12.23). The increase in the amount of primer was directly proportional to the increase of infiltration. All groups exhibited more gaps after thermomechanical aging. Conclusion: Using an excess of primer is not recommended because it reduces the µTBs and forms an unsatisfactory hybrid layer