Effect of occlusal calculus utilized as a potential "biological sealant" in special needs patients with gastric feeding tubes: a qualitative in vitro contrast to pit and fissure sealant restorations.

The aim of this case report and in vitro investigation was to evaluate the marginal microleakage of intact occlusal calculus of primary molars extracted from a special needs patient who received nutrition via a gastric feeding tube. An adolescent with a history of developmental disturbance presented for routine dental care in a hospital facility. Prophylaxis was performed, and 2 mandibular permanent molars were restored. Five primary molars were extracted due to mobility and delayed retention. Heavy deposits of intact calculus were present on the occlusal surfaces of the primary teeth. The extracted teeth were immersed in methylene blue dye solution, invested in acrylic resin, sectioned into blocks, and photographed at 20× and 40× magnification. Previously photographed calculus-free molars with pit and fissure sealants were reviewed and served as contrasting "restorations." The occlusal calculus on the primary teeth extracted from the patient absorbed the dye, while the comparison teeth containing pit and fissure sealants exhibited varying degrees of marginal dye penetration (microleakage). No marginal microleakage was noted in the calculus specimens, indicating that this substrate may serve as a "natural" occlusal surface sealant and that its removal from occlusal surfaces during routine oral prophylaxis may be unnecessary.

The impact of Er:YAG laser enamel conditioning on the microleakage of a new hydrophilic sealant--UltraSeal XT hydro.

UltraSeal XT hydro is a new hydrophilic, light-cured, methacrylate-based pit and fissure sealant which has been developed by Ultradent Products, USA. The sealant is highly filled with a 53 wt.% mixture of inorganic particles which confer both thixotropy and radiopacity. The principal purpose of this study was to investigate the microleakage of UltraSeal XT hydro as a function of different enamel etching techniques. The occlusal surfaces of sound, extracted human molars were either acid etched, Er:YAG laser irradiated or successively laser irradiated and acid etched. UltraSeal XT hydro was applied to each group of teeth (n = 10) which were subjected to a thermocycling process consisting of 2500 cycles between 5 and 50 °C with a dwell time of 30 s. Microleakage assessments were then carried out using 0.5% fuchsin dye and optical microscopy. The microleakage score data were analysed using the Kruskal-Wallis, Mann-Whitney U test with Bonferroni adjustment. No significant differences in microleakage were noted between the individually acid etched and laser-irradiated groups (p > 0.05); however, teeth treated with a combination of laser irradiation and acid etching demonstrated significantly lower microleakage scores (p < 0.001). Electron microscopy with energy-dispersive X-ray analysis revealed that the mineral filler component of UltraSeal XT hydro essentially comprises micrometre-sized particles of inorganic silicon-, aluminium- and barium-bearing phases. Laser etching increases the roughness of the enamel surface which causes a concentrated zoning of the filler particles at the enamel-sealant interface.

Influencia de la calidad de restauración coronal en el pronóstico de dientes tratados endodónticamente / Influence of the quality of coronal restoration in the prognosis of endodontically treated teeth

Introducción: la restauración de dientes tratados endodónticamente es compleja y controversial y su pronóstico está directamente relacionado con la calidad del tratamiento endodóntico y la restauración definitiva, lo que debe asegurar un correcto sellado marginal para evitar la filtración coronaria y el posterior fracaso endodóntico. Se ha demostrado que la aplicación de un inadecuado protocolo en el tratamiento del conducto posendodoncia podría causar fracasos por el arrastre y filtración de microorganismos que se encuentran en la cavidad oral y sus productos derivados hacia la porción apical de la raíz. Muchos factores a lo largo de las fases del tratamiento endorrestaurador influyen directamente en su pronóstico: calidad del sellado apical, cantidad de gutapercha remanente, desobturación temprana o tardía, capacidad de sellado de la restauración temporal o definitiva, desinfección del conducto, entre otras. Objetivo: actualizar a profesionales acerca de los parámetros clínicos a tener en cuenta en la rehabilitación de dientes tratados endodónticamente, que implica realizar todos los procedimientos bajo un estricto protocolo y una adecuada cadena aséptica para evitar contaminación bacteriana. Métodos: la búsqueda bibliográfica se llevó a cabo utilizando los siguientes términos: restauración coronal, microfiltración, desobturación radicular, calidad y estado endondóntico; se seleccionaron los artículos que evaluaron el efecto de la calidad de la obturación radicular, la restauración coronal o ambas, en el éxito de una endodoncia. Cincuenta y tres artículos fueron identificados y revisados por dos investigadores. Los datos fueron obtenidos de bases de datos como: Hinari, Sciencedirect, Wiley interscience, SciELO y fuentes indexadas nacionales e internacionales con criterios predeterminados. Resultados: de acuerdo con los conceptos de control de infección, todos los instrumentos y el material colocado dentro del conducto radicular deben ser estériles. La prevención de la microfiltración es un aspecto importante en el éxito del diente tratado endodónticamente, que debe ser rehabilitado en un período corto entre la endodoncia y la restauración definitiva, para reducir de forma considerable la contaminación. Conclusiones: sobre la base de la evidencia disponible se puede afirmar que, independiente de la técnica o material de obturación endodóntica o tipo de restauración, es indispensable mantener la cadena aséptica a lo largo de todo el tratamiento, lo que sumado a una adecuada restauración definitiva favorece la conservación del sellado a nivel coronal y apical que minimice al máximo el riesgo de contaminación bacteriana(AU)

Introduction: the restoration of endodontically treated teeth is complex and controversial, and its prognosis is directly related to the quality of endodontic treatment and the final restoration, which should ensure a proper marginal seal to prevent coronary filtration and avoid subsequent endodontic failure. It has been shown that to handle badly a post-endodontic canal could cause failures for skiddingand microorganisms filtration which are found in the oral cavity and derived products to the apical portion of the root. Many factors during the endo-restorer treatment phase directly influence in its prognosis: apical sealant quality, residual amount of gutta-percha, early or late desobturation, sealing ability of the temporary or permanent restoration, disinfection canal among other. Objective: the purpose is to update professionals about clinical parameters to take into account in the rehabilitation of endodontically treated teeth, for this it is necessary to follow all the procedures under strict protocol and proper aseptic chain to prevent bacterial contamination. Methods: the literature search was conducted using the following terms coronal restoration, microfiltration, desobturation root, quality and endodontic status, articles that evaluated the effect of the quality of the root filling and coronal restoration or both in the success of a root canal were selected. Fifty-three articles were identified and reviewed by two investigators. Data were obtained from databases such as: Hinari, Science Direct, Wiley interscience, and indexed sources national and indexed sources national and international to predetermined criteria. Results: according to the concepts of infection control, all instruments and equipment placed inside the root canal must be sterile. Prevention of microfiltration is an important success endodontically treated tooth appearance, which must be rehabilitated in a short period of time between endodontics and final restoration to significantly reduce contamination. Conclusions: based on the available evidence, the results say that regardless of the technical or endodontic filling material or type of temporary or permanent restoration, is essential to maintain the aseptic chain along the whole treatment which added to an adequate final restoration promote the conservation sealed coronal y apical level to reduce the risk of bacterial(AU)

Healing of a tooth with an overinstrumented apex, extensive transportation and periapical lesion using a 5 mm calcium hydroxide apical plug: an 8-year follow-up report

Besides the risk of filling material extrusion throughout the apex, a satisfactory apical seal can be difficult to achieve in canals with open apices or iatrogenic enlargements of the apical constriction. These situations pose a challenge to root canal filling. This paper describes the root canal filling of a maxillary right canine with an overinstrumented apex, complete loss of the apical stop, extensive canal transportation and apical periodontitis. A 5 mm calcium hydroxide apical plug was placed before root canal filling. The plug was made by soaking paper points with saline, dipping the points in calcium hydroxide powder and then applying it to the apex several times, until a consistent apical plug was obtained. The canal was then irrigated with saline in order to remove any residual calcium hydroxide from the root canal walls, dried with paper points and obturated with an inverted #80 gutta-percha cone and zinc oxide-eugenol based sealer by the lateral condensation technique. An 8-year radiographic follow-up showed formation of mineralized tissue sealing the apical foramen, apical remodeling and no signs of apical periodontitis.

Além do risco de extrusão periapical de material obturador pelo ápice, pode ser difícil conseguir um bom selamento apical em dentes com rizogênese incompleta ou alargamentos iatrogênicos da constrição apical. Casos assim representam um desafio durante a obturação do canal. Este caso clínico descreve a obturação de um canino superior direito com perda total da constrição apical por sobreinstrumentação, transporte excessivo e lesão periapical. Antes da obturação foi feito um tampão apical de hidróxido de cálcio com 5 mm de extensão. Para a realização do tampão, pontas de papel absorvente foram umedecidas em soro fisiológico, levadas ao pó do hidróxido de cálcio para absorvê-lo e aplicadas várias vezes no ápice até se conseguir um tampão apical consistente. Em seguida o canal foi irrigado com solução salina para a remoção de eventuais resíduos de hidróxido de cálcio das suas paredes, secado com pontas de papel absorvente e obturado com um cone #80 de guta percha invertido e cimento obturador à base de óxido de zinco e eugenol pela técnica da condensação lateral. O acompanhamento radiográfico de 8 anos mostrou selamento apical por tecido mineralizado, remodelação do ápice e reparo da lesão periapical.

Uso de incrustaciones de resina compuesta tipo onlay en molares estructuralmente comprometidos / Use of onlay-type composite resin inlays in structurally involved molars

Las incrustaciones en resina compuesta son una alternativa de bajo costo ante los métodos de obturación directos, frente a las dificultades de la adaptación marginal y la ubicación de contactos proximales, porque permiten otorgar una mejor anatomía dental a la restauración y superar el fenómeno de contracción al polimerizar grandes capas de material por fuera de la cavidad dental. El objetivo del presente artículo fue exponer el uso de la resina compuesta bajo técnica indirecta como una alternativa de fácil manipulación y resultados clínicos considerables ante la afectación estructural de molares. Se presentaron dos casos clínicos de incrustaciones con resina compuesta de tipo inlay onlay en dos molares permanentes afectados estructuralmente, uno de ellos fue tratado endodónticamente. Para la obtención de un troquel de trabajo sobre el que se confecciona la incrustación bajo técnica incremental se obtienen modelos al impresionar con alginato la arcada de los dientes seleccionados, se realiza vaciado en silicona liviana del diente preparado y el resto en yeso piedra tipo III. El proceso de cementación en la cavidad bucal se lleva a cabo con cemento resinoso de doble curado. Las incrustaciones fueron sometidas a un control a los seis meses para evaluar los signos de filtración o desadaptación marginal mediante el secado con aire de la jeringa triple, explorador y radiografías periapicales, que mostraron ausencia de desadaptación o pigmentación marginal. Se concluyó que ante la afectación estructural de molares, las incrustaciones con resina compuesta bajo técnica indirecta fueron de fácil manipulación y se obtuvieron satisfactorios resultados clínicos(AU)

The composite resin inlays are a low cost alternative which seeks improvements to the direct filling methods meet the challenges of the marginal adaptation, location of proximal contacts, allows us to improve the restoration dental anatomy and overcome the phenomenon of contraction at large sections of material polymerized outside the dental cavity. The objective of this article was to show the use of the composite with indirect technique how an alternative to easy handle and significant clinical results with the structural involvement of molars. The article reports two cases of composite resin inlay onlay in two permanent molars structurally affected, one endodontically treated. The collection of models is performed by the arch alginate impression of the teeth selected, making silicone light casting the prepared tooth and the rest in type III dental stone to obtain a die of work on drawing up the inlay in incremental technique. The cementation process oral cavity is carried out with dual cure resin cement. To control at six months for signs of a leak or marginal jet we used air-dried syringe, explorer and periapical X-Ray. The clinical examination and radiographic analysis revealed a good performance of the restorations in the absence of mismatch or marginal pigmentation. In conclusions the use of the composite inlays in molars with structural involvement with indirect technique is an alternative to easy handle and significant clinical results(AU)

Effect of Er:YAG laser application on the shear bond strength and microleakage between resin cements and Y-TZP ceramics.

The objective of this study was to investigate the effect of Er:YAG laser irradiation on shear bond strength and microleakage between resin cements and yttrium-stabilized tetragonal zirconia (Y-TZP) ceramics. Eighty disc specimens of Y-TZP ceramics (6 mm × 4 mm) were prepared. The specimens were divided into two groups according to surface treatment (control and Er:YAG laser-treated). The control and lased specimens were separated into two groups for shear bond strength test (n = 20), and microleakage evaluation (n = 10). Specimens were subjected to shear bond strength test by a universal testing machine with a crosshead speed of 1 mm/min. Specimens for microleakage evaluation were then sealed with nail varnish, stained with 0.5% basic fuchsin for 24 h, sectioned, and evaluated under a stereomicroscope. The data were analyzed with one-way ANOVA and post hoc Tukey-Kramer multiple comparisons tests (α = 0.05) for shear bond strengths and a two related-samples tests (α = 0.05) for microleakage scores. Higher bond strength values were found in the laser-treated groups compared to the control groups. Microleakage scores among the groups showed that the laser-treated specimens had lower microleakage scores than those of control specimens in the adhesive-ceramic interface. Roughening surface of Y-TZP ceramic by Er:YAG laser increased the shear bond strengths of ceramic to dentin and reduced the microleakage scores.

Healing of a tooth with an overinstrumented apex, extensive transportation and periapical lesion using a 5 mm calcium hydroxide apical plug: an 8-year follow-up report.

Besides the risk of filling material extrusion throughout the apex, a satisfactory apical seal can be difficult to achieve in canals with open apices or iatrogenic enlargements of the apical constriction. These situations pose a challenge to root canal filling. This paper describes the root canal filling of a maxillary right canine with an overinstrumented apex, complete loss of the apical stop, extensive canal transportation and apical periodontitis. A 5 mm calcium hydroxide apical plug was placed before root canal filling. The plug was made by soaking paper points with saline, dipping the points in calcium hydroxide powder and then applying it to the apex several times, until a consistent apical plug was obtained. The canal was then irrigated with saline in order to remove any residual calcium hydroxide from the root canal walls, dried with paper points and obturated with an inverted #80 gutta-percha cone and zinc oxide-eugenol based sealer by the lateral condensation technique. An 8-year radiographic follow-up showed formation of mineralized tissue sealing the apical foramen, apical remodeling and no signs of apical periodontitis.

Análisis crítico de metodologías empleadas en la evaluación de selladores en endodoncia / Critical analysis of methodologies used in the evaluation of sealants in endodontics

La incompleta obturación del sistema de conductos radiculares es uno de los motivos del fracaso en el tratamiento endodóntico. La presencia de espacios en el material obturador puede permitir la filtración en los sentidos apical y coronario. A medida que nuevos materiales son propuestos, se deben realizar investigaciones para la evaluación de todas sus propiedades. Dentro de ellas se puede destacar la capacidad selladora del material obturador en el interior de los conductos radiculares. Varias metodologías han sido preconizadas para esta finalidad. La literatura indica que han sido cuestionables la falta de estandarización y correlación entre estos métodos y los resultados de estas investigaciones. La falta de métodos confiables hace que estos materiales sean empleados en la práctica clínica de forma enpírica, en lo que respecta a esta propiedad. El propósito de este trabajo fue analizar metodologías de evaluación de la capacidad selladora de materiales obturadores endodónticos, buscando estudiar detalladamente sus variables y correlacionar los resultados de estas investigaciones con la práctica clínica

The incomplete filling of the root canal systen is one of the reasons for endodontic treatment failure. The presence of gaps in the seal material can allow leakage into the apical and coronary senses. As new materials are proposed, investigations must be conducted for the evaluation of all its properties. Within then you can highlight the sealing capacity of the filling material inside the root canals. Several methods have been advocated for this purpose. Therefore, the literature points towards the lack of standardization and correlation between these methods and the results of these investigations have been questionable. The lack of reliable methods makes the clinical use of these materials enpirical. The goal of this paper is to discuss methodologies for assessing the sealing ability of endodontic filling materials, seeking to study in detail the variables and correlate the results of these researchs with the clinical practice

Repair of amalgam restorations with conventional and bonded amalgam: an in vitro study / Reparo de restaurações de amálgama com amálgama adesivo e convencional: estudo in vitro

Purpose: This study evaluated microleakage on amalgam restorations repaired by amalgam and bonded amalgam. Methods: Thirty extracted human pre-molars were restored by amalgam. A simulated defect was prepared and assigned to two treatment groups (n=15): G1 - repaired by amalgam (Permite C-SDI); G2 - repaired by bonded amalgam (Caulk 34% Tooth Conditioner Gel - Dentsply + Prime & Bond 2.1 - Dentsply + Permite C- SDI). The teeth were immersed in a 50% silver nitrate solution, thermocycled and then, sectioned longitudinally through the restoration center and examined by 3 examiners using a stereomicroscope. Microleakage was evaluated in a 0-4 scale for dye penetration. Microleakage data were analyzed by Kruskal Wallis and Dunn test. Results: The bonded amalgam technique was significantly the most effective in repair/tooth interfaces sealing (score 0=53.3%, P=0.0012). For repair/restoration interfaces, conventional amalgam was also statistically more effective in the sealing (score 0=86.7%, P<0.001). Conclusion: None of materials eliminated microleakage completely. The use of adhesive systems had significant effect on the ability to seal the repair/tooth interface, however, for repair/restoration interface, it can increase microleakage.

Objetivo: Avaliar a microinfiltração em restaurações de amálgama com reparo em amálgama ou amálgama adesivo. Métodos: Trinta pré-molares humanos extraídos foram restaurados com amálgama. Simulou-se um defeito nas restaurações reparado com: G1 - amálgama (n=15) (Permite C-SDI); G2 - amálgama adesivo (n=15) (Caulk 34% Condicionador dentário Gel - Dentsply + Prime & Bond 2.1 - Dentsply + Permite C-SDI). Os dentes foram imersos em solução de nitrato de prata a 50%, termociclados e então, secionados longitudinalmente através da restauração e examinados por três examinadores usando um estereomicroscópio. A microinfiltração foi avaliada pela penetração de corante com uma escala de 0 a 4. Diferenças entre os grupos foram verificadas pelos testes Kruskal Wallis e Dunn. Resultados: Na interface reparo/dente, a técnica de reparo com amálgama adesivo foi significativamente mais efetiva, apresentando menor microinfiltração (escore 0=53.3%, P= 0,0012). Já na interface reparo/restauração, houve menor microinfiltração nas restaurações reparadas com amálgama convencional (escore 0=86.7%, P<0,001). Conclusão: Nenhum dos materiais eliminou a microinfiltração completamente. O uso de sistemas adesivos tem efeito significativo no selamento da interface reparo/dente, entretanto para interface reparo/restauração, ele pode aumentar a microinfiltração.

Class I and Class V composite restorations: Influence of light-curing techniques on microleakage / Restaurações de Classes I e V: influência das técnicas de fotoativação na microinfiltração

Purpose: To evaluate the effect of light-curing techniques on in vitro microleakage of class I and class V composite restorations. Methods: Sixty human premolars were used to prepare 30 class I and 30 class V cavities, which were cleaned and treated with one step self-etching adhesive (Xeno III - Dentsply). A resin composite (TPH 3 - Dentsply) was inserted in two layers and light-cured using two protocols (n=15 each): conventional curing (500 mW/cm ² , 30 s each increment) and pulse delay technique (first increment similar to the conventional technique and the last increment initially cured with 200 mW/cm ² for 3s and after 5 min light-cured again with 500 W/cm² for 30 s). The specimens were polished, submitted to 800 thermal cycles, sealed, and immersed in a 2% basic fuchsin solution. The teeth were cleaned, sliced, and scored according to the dye penetration. Data were analyzed by Mann-Whitney U test. Results: In class I cavities the pulse delay light-curing technique showed statistically significant better sealing than the conventional technique. In class V restorations no difference was detected between the two techniques in enamel and dentin.Conclusion: Light-curing technique affected the microleakage in class I composite restorations but not in class V.

Objetivo: Avaliar o efeito da técnica de fotoativação na microinfiltração in vitro em cavidades de classes I e V restauradas com resina composta. Metodologia: Em 60 pré-molares humanos, foram confeccionadas cavidades de classe I em 30 dentes e de classe V nos demais 30 dentes. As cavidades foram limpas e tratadas com o sistema adesivo autocondicionante de um passo (Xeno III - Dentsply). A resina composta (TPH 3 - Dentsply) foi inserida em dois incrementos e fotoativada de dois modos (n=15 cada): A) Convencional, sendo cada incremento fotoativado com intensidade de 500mW/cm ² por 30 s; B) Pulso tardio, sendo o primeiro incremento fotoativado da mesma forma que o grupo convencional e o último incremento inicialmente fotoativado com 200mW/cm ² , durante 3 s, 5 min de espera e fotoativação final com 500 mW/cm ² por 30 s. Os espécimes foram polidos, submetidos a 800 ciclos térmicos, impermeabilizados e imersos em fucsina básica a 2%. Os dentes foram limpos, seccionados e avaliados quanto à penetração do corante usando-se escores de 0 a 5. Os dados foram analisados por teste U de Mann-Whitney. Resultados: Nas cavidades de classe I houve diferença estatisticamente significativa entre os grupos. Nas cavidades de classe V não houve diferença entre os dois métodos de fotoativação, tanto em margem de esmalte quanto em dentina. Conclusão: Em cavidades de classe I a fotoativação por pulso tardio proporcionou maior vedamento marginal que a fotoativação convencional. Em cavidades de classe V não houve diferença de penetração do corante.

[The importance of microleakage in endodontics: conclusions for the endodontic practice]. / Mikroszivárgás jelentôsége az endodonciában--a gyakorlat számára levonható következtetések.

There is a difference between the clinically and even radiographically determined success for endodontic therapy. One of the main reasons for reduced success rate is the poor quality of root canal treatment namely the presence of microleakage. Shortcomings created during preparation, including canal transportation and canal deformities resulted in reduced healing rate of treated cases. Curvatures or irregular shape can hamper the proper cleaning of the whole root canal even by the latest generation of instruments available on the market. More recently published papers have emphasized the increasing role of usage of chemical agents to complete debridement of the root canal system. Some authors suggested to replace the root canal instrumentation with using special kind of chemical agents more frequently. Does the introduction of non instrumentation technique or another kind of idea for cleaning and shaping of the root canal system can significantly change the treatment outcome of the root canal fillings in the future?

Short-term evaluation of resin sealing and rebonding on amalgam microleakage: an SEM observation.

AIMS: The aim of this study was to evaluate the effect of two different sealing agents on the microleakage of Class V amalgam restorations with and without resin rebonding. METHODS AND MATERIALS: Sixty extracted premolars were divided into six groups with ten teeth in each group. Class V cavity preparations were prepared on the facial surfaces of each tooth with the coronal margins placed in enamel and apical margins in cementum (dentin). The preparations in three groups were treated with Copalite, Scotchbond Multi-Purpose (SBMP), and no sealing agent, respectively. The other three groups received the same sealing agents in conjunction with a rebonding process. This arrangement of specimens provided for a comparison of the groups with and without a rebonding procedure. Amalgam was used as the restorative material. Specimens were thermocycled, stained, and sectioned. Microleakage was graded (0-3) using a stereomicroscope at 40x magnification. A scanning electron microscope (SEM) was used along with a high resolution elemental analysis. Data were analyzed with Kruskal-Wallis, Mann-Withney, and Wilcoxon pair wise statistical tests (alpha=.05). RESULTS: The bonded amalgam groups demonstrated significantly less microleakage, whereas the unsealed groups showed the highest microleakage (P=0.001). A significant difference between the mean rank of the microleakage of enamel and dentin margins was observed (P=0.037). Insignificant, lower microleakage was observed in groups receiving a rebonding procedure (P=0.085). CONCLUSION: Copalite and a multi-step adhesive system had a significant effect on microleakage of Class V amalgam restorations. The influence of the multi-step adhesive system was significantly greater than Copalite. The rebonding of the amalgam restorations did not have a significant effect on microleakage.

Avaliação in vitro da capacidade de selamento coronário de três materiais usados como barreira adicional, em dentes tratados endodonticamente, obturados com diferentes cimentos endodônticos, utilizando o método de filtração de fluído / In vitro fluid filtration evaluation of intracoronal sealing ability of three materials used as secondary barrier

Grande parte dos insucessos dos tratamentos endodônticos ocorre por falha nas restaurações provisórias ou definitivas, em função da microinfiltração coroa-ápice. Sabe-se que, muitos pacientes realizam esse tratamento, mas não têm condições de restaurar o dente imediatamente, aumentando o risco de falhas nesse período intermediário, pela penetração de bactérias ou fluídos bucais até o canal radicular. Nos últimos anos, têm-se buscado, após o tratamento endodôntico, realizar o selamento intracoronário imediato, visando assim uma maior longevidade dessa terapia, até que se realize a restauração definitiva, ou até mesmo após esta. Diversas substâncias estão sendo testadas com o objetivo de avaliar essa penetração e existem diversos métodos disponíveis, para se avaliar a efetividade do selamento, como o de penetração de corantes e bactérias. Ultimamente, o método de filtração de fluído, que foi desenvolvido inicialmente para avaliar a permeabilidade dentinária, mas que posteriormente foi adaptado para uso em outras áreas, tem sido bastante utilizado para avaliar a microinfiltração em dentes tratados endodonticamente. Esse método é considerado quantitativo, não destrutivo, pela capacidade de se utilizar os mesmos espécimes em diferentes períodos de tempo, apresentando assim vantagens sobre os demais. Em função disso, o objetivo deste trabalho foi investigar, através do método de filtração de fluído, a permeabilidade de diferentes materiais utilizados no selamento intracoronário: o IRM, o Adper Scothbond Multi Purpose Plus e o Adper Single Bond 2, em dentes humanos unirradiculares obturados com cimento AH Plus e cones de guta percha, comparando-as entre si e também com a capacidade de selamento do novo sistema Epiphany, sendo as avaliações realizadas em períodos de 15, 30 e 60 dias. Após a aplicação do teste não paramétrico de Kruskall-Wallis e de Friedman, diferenças significantes foram encontradas entre os quatro grupos, sendo que o Grupo do IRM apresentou as maiores médias de filtrações em todos os períodos, e os grupos selados com os dois sistemas adesivos as menores. O sistema Epiphany apresentou médias iniciais baixas, mas sofreu um aumento significante dos seus valores de filtrações no último período, provavelmente por não ter recebido nenhum material selador secundário

Effect of diode laser irradiation on the apical sealing of MTA retrofillings.

Apical sealing is essential for the success of paraendodontic surgery, so any procedure that may favor an adequate sealing of the apical remainder should be performed. The purpose of this study was to evaluate the influence of diode laser irradiation on the apical sealing of root-end cavities with MTA retrofillings. Root canals in twenty extracted human teeth were shaped with K-files and filled with gutta-percha. The apexes were cut off and root-end preparations were performed. The roots were divided randomly in 2 groups. Group 1 (ten specimens) was retrofilled with MTA. Group 2 was irradiated with diode laser, with 1 W for 20 seconds, on the apical surface and root end cavity before retrofilling with MTA. The specimens had their external surfaces impermeabilized with cyanoacrylate, except for the apical surface, and were then immersed in 1% rhodamine B dye for 72 h and placed in plaster stone. After that, the specimens were submitted to longitudinal abrasion until half of the root remained. The linear dye leakage was observed in these mid-roots between the root canal wall and retrofilling. The linear dye leakage was measured with Image Lab software, and the results were statistically analyzed with Student's t test. There were no statistically significant differences between the two groups (p > 0.05). The diode laser irradiation did not improve the apical sealing of MTA retrofillings under the conditions of this in vitro study.

Effect of diode laser irradiation on the apical sealing of MTA retrofillings / Efeito da irradiação de laser de diodo no selamento apical em retrobturações com MTA

Apical sealing is essential for the success of paraendodontic surgery, so any procedure that may favor an adequate sealing of the apical remainder should be performed. The purpose of this study was to evaluate the influence of diode laser irradiation on the apical sealing of root-end cavities with MTA retrofillings. Root canals in twenty extracted human teeth were shaped with K-files and filled with gutta-percha. The apexes were cut off and root-end preparations were performed. The roots were divided randomly in 2 groups. Group 1 (ten specimens) was retrofilled with MTA. Group 2 was irradiated with diode laser, with 1 W for 20 seconds, on the apical surface and root end cavity before retrofilling with MTA. The specimens had their external surfaces impermeabilized with cyanoacrylate, except for the apical surface, and were then immersed in 1 percent rhodamine B dye for 72 h and placed in plaster stone. After that, the specimens were submitted to longitudinal abrasion until half of the root remained. The linear dye leakage was observed in these mid-roots between the root canal wall and retrofilling. The linear dye leakage was measured with Image Lab software, and the results were statistically analyzed with Student's t test. There were no statistically significant differences between the two groups (p > 0.05). The diode laser irradiation did not improve the apical sealing of MTA retrofillings under the conditions of this in vitro study.

O selamento apical é fundamental para o sucesso da cirurgia parendodôntica. Assim, procedimentos que melhorem o selamento do remanescente apical devem ser utilizados. O objetivo deste estudo foi verificar se a irradiação de laser de diodo poderia aumentar o selamento apical em cavidades retrógradas obturadas com MTA. Foram utilizadas 20 raízes de dentes humanos extraídos que, após preparo com lima tipo K, tiveram seus canais obturados com guta-percha. Os ápices foram cortados e sofreram preparo de cavidades retrógradas. As raízes foram divididas aleatoriamente em 2 grupos. O grupo 1 (dez espécimes) foi retrobturado com MTA, e o grupo 2 sofreu irradiação de laser de diodo na potência de 1 W por 20 s na superfície apical e na cavidade retrógrada antes da obturação com MTA. Os espécimes foram impermeabilizados externamente com cianoacrilato, com exceção da superfície apical, imersos em corante rodamina B a 1 por cento por 72 h, incluídos em gesso e posteriormente desgastados no sentido longitudinal até obter-se metade da raiz. Foi feita a leitura da infiltração linear do corante nessas hemi-raízes, entre a parede do canal radicular e a retroobturação, com auxílio do programa de computação Image Lab. Os resultados foram analisados estatisticamente pelo Teste t de Student. Não houve diferença estatística significante entre os dois grupos (p > 0,05). A irradiação com laser de diodo não proporcionou aumento do selamento apical em retrobturações com MTA sob as condições do presente estudo in vitro.

Effect of light-curing method on marginal adaptation, microleakage, and microhardness of composite restorations.

The objective of this study was to investigate the effects of different light-curing methods on microleakage, marginal adaptation, and microhardness of composite restorations. Slot-type preparations were made in bovine teeth, with gingival margins on dentin. Specimens were divided into 12 groups (n = 12) according to composite-light-curing unit (LCU) combinations. Three composites were used: Filtek Supreme, Herculite XRV, and Heliomolar. All restorations were placed using the same adhesive. Four LCUs were used: a quartz-tungsten-halogen (QTH) LCU (Optilux 501), a first-generation light-emitting diode (LED) LCU (FreeLight 1), and two second-generation LED LCUs (FreeLight 2 and Translux Power Blue). After finishing and polishing, specimens were subjected to mechanical load cycling (100,000 cycles). Gingival margin adaptation was determined as a function of gap formation using epoxy replicas. Microleakage was evaluated by measuring dye penetration across the gingival wall in cross-sectioned specimens. Microhardness was measured as Knoop Hardness number (KHN) at different occluso-gingival locations in cross-sectioned specimens. Data were analyzed for statistical significance (p = 0.05) using appropriate statistical tests. Marginal adaptation was affected by load-cycling in most specimens, but no significant differences were observed among composites and LCUs. Microleakage was not affected by LCU, except for Heliomolar specimens which when cured with Optilux 501 resulted in higher microleakage scores than those obtained with the other LCUs. For microhardness, Translux Power Blue generally produced the highest values and the FreeLight 1 produced the lowest. The performance of the second-generation LED LCUs generally was similar to that of the QTH control, and better than that of the first-generation LED unit.

The effect of insertion and photopolymerization techniques on microleakage of class V cavities--a quantitative evaluation.

The aim of this in vitro study was to evaluate by spectrophotometry the influence of the incremental technique and progressive light curing in the microleakage of Class V cavities. Forty samples were prepared with class V cylindrical cavities on the buccal root surface of bovine incisive teeth and filled with composite resin (Z250). The samples were divided into four groups: I: cavity was bulk filled and the composite was light cured for 40 seconds; Group II: cavity was bulk filled and a 'soft-start" polymerization was used; Group III: cavity was filled with the incremental technique in two coats and light cured for 40 seconds; Group IV: cavity was filled with the incremental technique in two coats and light cured with "soft-start" polymerization. After the restoration, the specimens were thermally stressed for 3,000 cycles in bath at 5 +/- 2 degrees C and 55 +/- 2 degrees C, protected with nail enamel, colored with 2% methylene blue and cut into sections. These sections were triturated and the dye was recovered with PA ethanol and the supernatant was evaluated. The data were submitted to ANOVA and the results showed the following averages: bulk filled and conventional photopolymerization (I) 0.06075 microg/ml; bulk filled and progressive photopolymerization (II) 0.04030 microg/ml; incremental insertion and conventional photopolymerization (III) 0.04648 microg/ml; incremental insertion and progressive photopolymerization (IV) 0.04339 microg/ml. No significant statistic differences were observed among the mean values. The Degulux "soft-start" equipment probably emits too high initial light intensity to promote progressive photopolymerization.

Avaliação da infiltração marginal em molares decíduos utilizando um sitema adesivo autocondicionante e um monocomponente / Microleakage evaluation in deciduous molars using self-etching and single=bottle adhesive systems

Este estudo avaliou in vitro a microinfiltração marginal em dentes decíduos restaurados com um sistema adesivo monocomponente e um autocondicionante. Nas faces distais de 20 molares decíduos foram confeccionadas cavidades classe II, sendo os dentes divididos em 2 grupos: G1: Prime & Bond 2.1 + Z-250 e G2: Adhese Z-250. Após ciclagem térmica (300 ciclos), impermeabilização e imersão em solução corante de azul de metileno a 0,5 por cento, as amostras foram selecionadas e avaliadas por um examinador calibrado, com lupa de 10x de aumento. Os resultados foram avaliados através do teste não paramétrico de Kruskall-Wallis. As médias dos postos foram: G1 = 27,6 e G2 = 31,5. Conclui-se que os adesivos apresentaram comportamento semelhante, não existindo diferenças estatisticamente significantes entre os grupos

The effect of insertion and photopolymerization techniques on microleakage of Class V cavities: a quantitative evaluation

O objetivo deste estudo in vitro foi avaliar através de espectrofotometria a influência das técnicas de inserção incremental e de fotopolimerização progressiva na microinfiltração de cavidades Classe V. Foram preparadas 40 cavidades cilíndricas na superfície radicular vestibular de incisivos bovinos e preenchidas com resina composta (Z250). Os espécimes foram divididos em quatro grupos: I: a resina foi inserida em camada única e fotopolimerizada por 40 segundos; II: a resina foi inserida em camada única e fotopolimerizada progressivamente com um aparelho "soft-start"; III: a resina foi inserida em duas camadas e fotopolimerizada por 40 segundos; IV: a resina foi inserida em duas camadas e fotopolimerizada progressivamente. Em seguida os espécimes foram submetidos a 3.000 ciclos térmicos a 5 ± 2°C e 55 ± 2°C, preparados, corados com azul de metileno a 2%, seccionados, triturados e avaliados em espectrofotometria para se quantificar o corante infiltrado. Os dados foram submetidos a ANOVA. Os resultados demonstraram as seguintes médias: inserção única e fotopolimerização convencional (I): 0,06075 µg/ml; inserção única e fotopolimerização progressiva (II): 0,04030 µg/ml; inserção incremental e fotopolimerização convencional (III): 0,04648 µg/ml; inserção incremental e fotopolimerização progressiva (IV): 0,04339 µg/ml. Não foram encontradas diferenças estatísticas significativas entre as médias. Observou-se que o aparelho Degulux "soft-start" emite uma intensidade de luz inicial muito alta para promover fotopolimerização progressiva.