Effect of the root canal final rinse protocols on the debris and smear layer removal and on the push-out strength of an epoxy-based sealer

The aim of the present study was to evaluate the efficacy of QMiX, SmearClear, and 17% EDTA for the debris and smear layer removal from the root canal and its effects on the push-out bond strength of an epoxy-based sealer by scanning electron microscopy (SEM). Forty extracted human canines (n=10) were assigned to the following final rinse protocols: G1-distilled water (control), G2-17% EDTA, G3-SmearClear, and G4-QMiX. The specimens were submitted to a SEM analysis to evaluate the presence of debris and smear layer, respectively, in the apical or cervical segments. In sequence, forty extracted human maxillary canines with the root canals instrumented were divided into four groups (n=10) similar to the SEM analysis study. After the filling with AH Plus, the roots were transversally sectioned to obtain dentinal slices. The specimens were submitted to a push-out bond strength test using an electromechanical testing machine. The statistical analysis for the SEM and push-out bond strength studies were performed using the Kruskal-Wallis and Dunn tests (α=5%). There was no difference among the G2, G3, and G4 efficacy in removing the debris and smear layer (P>0.05). The efficacy of these groups was superior to the control group. The push-out bond strength values of G2, G3, and G4 were superior to the control group. The ability to remove the debris and smear layer by SmearClear and QMiX was as effective as the 17% EDTA. The final rinse with these solutions promoted similar push-out bond strength values. © 2013 Wiley Periodicals, Inc.

Physicochemical and mechanical properties of zirconium oxide and niobium oxide modified Portland cement-based experimental endodontic sealers

Aim: To evaluate the physicochemical and mechanical properties of Portland cement-based experimental sealers (ES) with different radiopacifying agents (zirconium oxide and niobium oxide micro- and nanoparticles) in comparison with the following conventional sealers: AH Plus, MTA Fillapex and Sealapex. Methodology: The materials were tested for setting time, compressive strength, flow, film thickness, radiopacity, solubility, dimensional stability and formaldehyde release. Data were subjected to anova and Tukey tests (P < 0.05). Results: MTA Fillapex had the shortest setting time and lowest compressive strength values (P < 0.05) compared with the other materials. The ES had flow values similar to the conventional materials, but higher film thickness (P < 0.05) and lower radiopacity (P < 0.05). Similarly to AH Plus, the ES were associated with dimensional expansion (P > 0.05) and lower solubility when compared with MTA Fillapex and Sealapex (P < 0.05). None of the endodontic sealers evaluated released formaldehyde after mixing. Conclusion: With the exception of radiopacity, the Portland cement-based experimental endodontic sealers presented physicochemical properties according to the specifications no 57 ANSI/ADA (ADA Professional Product Review, 2008) and ISO 6876 (Dentistry - Root Canal Sealing Materials, 2012, British Standards Institution, London, UK). The sealers had setting times and flow ability that was adequate for clinical use, satisfactory compressive strength and low solubility. Additional studies should be carried out with the purpose of decreasing the film thickness and to determine the ideal ratio of radiopacifying agents in Portland cement-based root canal sealers. © 2013 International Endodontic Journal.

Damage Detection Based on Electromechanical Impedance Principle and Principal Components

This paper presents a novel time domain approach for Structural Health Monitoring (SHM) systems based on Electromechanical Impedance (EMI) principle and Principal Component Coefficients (PCC), also known as loadings. Differently of typical applications of EMI applied to SHM, which are based on computing the Frequency Response Function (FRF), in this work the procedure is based on the EMI principle but all analysis is conducted directly in time-domain. For this, the PCC are computed from the time response of PZT (Lead Zirconate Titanate) transducers bonded to the monitored structure, which act as actuator and sensor at the same time. The procedure is carried out exciting the PZT transducers using a wide band chirp signal and getting their time responses. The PCC are obtained in both healthy and damaged conditions and used to compute statistics indexes. Tests were carried out on an aircraft aluminum plate and the results have demonstrated the effectiveness of the proposed method making it an excellent approach for SHM applications. Finally, the results using EMI signals in both frequency and time responses are obtained and compared. © The Society for Experimental Mechanics 2014.

Produção de biodiesel a partir de óleo residual reciclado e realização de testes comparativos com outros tipos de biodiesel e proporções de mistura em um moto-gerador

Pós-graduação em Engenharia Mecânica - FEIS

Eficácia e período residual do diflubenzuron para o controle de larvas de Aedes aegypti resistentes ao temefós

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Expressão de genes relacionados à função mitocondrial em bovinos Nelore extremos para consumo alimentar residual

Pós-graduação em Genética e Melhoramento Animal - FCAV

Estudo dos mecanismos de instabilidade em solos residuais de biotita-gnaisse da bacia do ribeirão Guaratinguetá

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação do processo de infiltração da água em solo residual de Biotita-gnaisse para superfícies com diferentes declividades utilizando lisímetros

Pós-graduação em Engenharia Civil e Ambiental - FEB

Avaliação da deslignificação com oxigênio utilizando residual da planta química do dióxido de cloro do licor branco oxidado

Pós-graduação em Engenharia Mecânica - FEG

Estudo sobre os efeitos de tensões residuais na vida em fadiga da liga de alumínio 6013-T6, em perfil tubular, submetidas a shot peening

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Caracterização do consumo alimentar residual e relações com desempenho e características de carcaça de bovinos nelore

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito de genótipos de feijoeiro, óleo de nim em diferentes formulações e período residual no controle de Zabrotes subfasciatus (Boheman, 1833)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito de produtos a base de óleo de nim em diferentes formulações no controle de Plutella xylostella (L.,1758) (Lepidoptera: Plutellidae), em couve

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Ação de fungicidas e acibenzolar-se-methyl no controle da pinta preta do tomateiro

Pós-graduação em Agronomia (Proteção de Plantas) - FCA

Desenvolvimento de método analítico para determinação de ozônio residual em água utilizando a ténica de fluorescência e estudo da viabilidade da construção de um sensor fluorimétrico em uma gota de solução para determinação de ozônio em ar

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)