Root surface treatment using diode laser in delayed tooth replantation: radiographic and histomorphometric analyses in rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Confocal Laser Microscopic Analysis of Biofilm on Newer Feldspar Ceramic

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

In vitro evaluation of the effectiveness of irrigants and intracanal medicaments on microorganisms within root canals

Aim To evaluate in vitro the effectiveness of sodium hypochlorite (NaOCl). chlorhexidine (CHX) and live intracanal medicaments on microorganisms within root canals.Methodology Ninety-six human single-rooted extracted teeth were used. After removing the crowns, canal preparation was completed and the external root Surfaces were coated with epoxy resin. Following sterilization. The teeth were contaminated with Candida albicans and enterococcus faecalis. and were incubated at 37 +/- 1 degreesC for 7 days. The teeth were divided according to the irrigant solution or intracanal medicament: group 1. sterile physiologic solution (SPS) and calcium hydroxide (Ca(OH)(2)) paste: group 2. SPS and camphorated paramonochlorophenol (CPMC): group 3.SPS and tricresol formalin: group 4, SPS and CaOH2 + CPMC paste: group 5, SPS and PMC furacin; group 6.2.5%, NaOCl without intracanal medication: group 7, 2.0% CHX without intracanal medication and group 8, SPS Without intracanal medication (control group). Microbiological samples were collected with sterile paper points, and bacterial growth was determined. The data were submitted to the analysis of variance (ANOVA. P = 0.05).Results For C. albicans, groups 3 and S were statistically less effective than groups 1, 2. 4 and 5 (Kruskal-Wallis (K-W) = 65.241; gl = 7; P = 0.001). For E. faecalis, groups 6 and 8 were statistically less effective than groups 1-4 and 7 (K-W = 61.048; gl = 7; P = 0.001).Conclusions Ca(OH)(2) + CPMC paste was the most effective intracanal medicament for the elimination of the two microorganisms; 2.0% CHX solution was more effective than 2.5% NaOCl against E. faecalis.

In vitro evaluation of dental bleaching effectiveness using hybrid lights activation

OBJETIVO: Avaliar se fontes de luz aumentam a eficácia do peróxido de hidrogênio na técnica de clareamento profissional. METODOLOGIA: Foram empregados 60 dentes incisivos bovinos, com dimensões coronárias e radiculares padronizadas a partir do limite amelo-cementário, sendo descartada a porção lingual. Os corpos-de-prova (cp) foram limpos em ultra-som por 20 min e a dentina condicionada com H3PO4 a 38% por 15 s, sendo os (cp) imersos em solução de café solúvel a 25% por duas semanas. A dentina foi impermeabilizada com esmalte e os (cp) divididos em 5 grupos, sendo a cor inicial mensurada através do espectofotômetro-EasyShade (VITA). Todos os (cp) receberam três aplicações por 10 min do gel clareador Opalescence Xtra-Boost (Ultradent) conforme segue: Grupo 1 - controle, não recebeu fotoativação, Grupo 2 - ativado com luz halôgena, Grupo 3 - ativado com LED azul/LASER, Grupo 4 - ativado com LED verde/LASER e Grupo 5 - ativado com LED vermelho. Após o clareamento foi mensurada a variação de cor E, a*, b*e L* e as referentes à escala de cor Vita Clássico. Os dados foram submetidos à análise de variância, teste de Tukey e de Dunn (α=5%). RESULTADOS: A diferença geral da cor foi reduzida quando se empregou LED Azul e Luz Halógena, sendo que o desempenho do peróxido de hidrogênio a 38% foi intensificado dependendo da fonte de luz utilizada. A avaliação quantitativa de cor, obtida por espectrofotômetro e pela escala de cor Vita Clássico, foram coincidentes. CONCLUSÃO: O tipo de fonte de luz empregada interfere na eficácia do agente clareador.

Surface roughness of enamel and four resin composites

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

ANTIMICROBIAL ACTIVITY of SODIUM HYPOCHLORITE ASSOCIATED WITH INTRACANAL MEDICATION FOR Candida albicans and Enterococcus faecalis INOCULATED IN ROOT CANALS

Objective: The purpose of this study was to evaluate the action of sodium hypochlorite (NaOCl) associated with an intracanal medication against Candida albicans and Enterococcus faecalis inoculated in root canals. Material and Methods: Thirty-six human single-rooted teeth with single root canals were used. The canals were contaminated with C. albicans and E. faecalis for 21 days and were then instrumented with 1% NaOCl. The roots were divided into 3 groups (n=12) according to the intracanal medication applied: calcium hydroxide paste, 2% chlorhexidine (CHX) gel, and 2% CHX gel associated with calcium hydroxide. The following collections were made from the root canals: a) initial sample (IS): 21 days after contamination (control), b) S1: after instrumentation, c) S2: 14 days after intracanal medication placement; S3: 7 days after intracanal medication removal. The results were analyzed statistically by the Kruskal-Wallis test at 5% significance level. Results and Conclusions: Both 1% NaOCl irrigation and the intracanal medications were effective in eliminating E. faecalis and C. albicans inoculated in root canals.

BOND STRENGTH DURABILITY of SELF-ETCHING ADHESIVES and RESIN CEMENTS TO DENTIN

Objectives: To evaluate the microtensile bond strength (mu TBS) of one-(Xeno III, Dentsply) and two-step (Tyrian-One Step Plus, Bisco) self-etching adhesive systems bonded to dentin and cemented to chemically cured (C&B Metabond) or light-cured paste of a dual-cure resin cement (Variolink II, Ivoclar) within a short (24 h) and long period of evaluation (90 days). Material and Methods: Forty recently extracted human molars had their roots removed and their occlusal dentin exposed and ground wet with 600-grit SiC paper. After application of one of the adhesives, the resin cement was applied to the bonded surface and a composite resin block was incrementally built up to a height of 5 mm (n = 10). The restored teeth were stored in distilled water at 37 C for 7 days. The teeth were then cut along two axes (x and y), producing beam-shaped specimens with 0.8 mm(2) cross-sectional area, which were subjected to mu TBS testing at a crosshead speed of 0.05 mm/min and stressed to failure after 24 h or 90 days of storage in water. The mu TBS data in MPa were subjected to three-way analysis of variance and Tukey's test (alpha = 0.05). Results: The interaction effect for all three factors was statistically significant (three-way ANOVA, p < 0.001). All eight experimental means (MPa) were compared by the Tukey's test (p < 0.05) and the following results were obtained: Tyrian-One Step Plus /C&B/24 h (22.4 +/- 7.3); Tyrian-One Step Plus /Variolink II/24 h (39.4 +/- 11.6); Xeno III/C&B/24 h (40.3 +/- 12.9); Xeno III/Variolink II/24 h (25.8 +/- 10.5); Tyrian-One Step Plus / C&B/90 d (22.1 +/- 12.8) Tyrian-One Step Plus/VariolinkII/90 d (24.2 +/- 14.2); Xeno III/C&B/90 d (27.0 +/- 13.5); Xeno III/Variolink II/90 d (33.0 +/- 8.9). Conclusions: Xeno III/Variolink II was the luting agent/adhesive combination that provided the most promising bond strength after 90 days of storage in water.

Roughness of Human Enamel Surface Submitted to Different Prophylaxis Methods

The purpose of this in vitro study was to evaluate alterations in the surface roughness and micromorphology of human enamel submitted to three prophylaxis methods. Sixty-nine caries-free molars with exposed labial surfaces were divided into three groups. Group I was treated with a rotary instrument set at a low speed, rubber clip and a mixture of water and pumice; group II with a rotary instrument set at a low speed, rubber cup and prophylaxis paste Herjos-F (Vigodent S/A Industria e Comercio, Rio de Janeiro, Brazil); and group III with sodium bicarbonate spray Profi II Ceramic (Dabi A dante Indtistrias Medico Odontologicas Ltda, Ribeirao Preto, Brazil). All procedures were performed by the same operator for 10 s, and samples were rinsed and stored in distilled water. Pre and post-treatment surface evaluation was completed using a surface profilometer (Perthometer S8P Marh, Perthen, Germany) in 54 samples. In addition, the other samples were coated with gold and examined in a scanning electron microscope (SEM). The results of this study were statistically analyzed with the paired t-test (Student), the Kruskal-Wallis test and the Dunn (5%) test. The sodium bicarbonate spray led to significantly rougher surfaces than the pumice paste. The use of prophylaxis paste showed no statistically significant difference when compared with the other methods. Based on SEM analysis, the sodium bicarbonate spray presented an irregular surface with granular material and erosions. Based on this study, it can be concluded that there was an increased enamel stuface roughness when teeth were treated with sodium bicarbonate spray when compared with teeth treated with pumice paste.

Synthesis and characterization of mesoporous TiO2 nanostructured films prepared by a modified sol-gel method for application in dye solar cells

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Estudo eletroquímico de Fe[Fe(CN)5NO] em eletrodo de pasta de grafite

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Determinação de chumbo em álcool combustível por voltametria de redissolução anódica utilizando um eletrodo de pasta de carbono modificado com resina de troca iônica Amberlite IR 120

Um método envolvendo a pré-concentração e redissolução anódica em condições de voltametria de pulso diferencial empregando um eletrodo de pasta de carbono modificado (EPCM) com uma resina de troca iônica Amberlite IR120 foi proposto para a determinação de íons chumbo em álcool combustível. O procedimento é baseado em um pico de oxidação do analito observado em -0,53 V(vs. Ag/AgCl) em solução de HCl. As melhores condições experimentais encontradas foram: 5% (m/m) da Amberlite IR120 para a construção do eletrodo, solução de HCl 0,1 mol L-1, velocidade de varredura de 10 mVs-1, tempo de pré-concentração de 15 min e amplitude de pulso de 100 mV. Utilizando essas condições, o EPCM apresentou uma resposta linear entre a corrente de pico anódica e a concentração de íons chumbo para o intervalo entre 9,9 x 10-9 e 1,2 x 10-6 mol L-1 e um limite de detecção de 7,2 x 10-9 mol L-1. Valores de recuperação entre 96 % e 102 % foram encontrados para amostras de álcool combustível enriquecidas com Pb2+ em níveis de 10-7 mol L-1. O efeito da presença de outros íons concomitantes sobre a resposta voltamétrica do eletrodo também foi avaliado.

Cobalt phthalocyanine as a biomimetic catalyst in the amperometric quantification of dipyrone using FIA

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Eletrodo de pasta de carbono em minicavidade de contato sólido

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Electrochemical and theoretical evaluation of the interaction between dna and amodiaquine: evidence of the guanine adduct formation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effects of a non-rinse conditioner on the enamel of primary teeth

O objetivo deste estudo in vitro foi de avaliar ao microscópio eletrônico de varredura os aspectos morfológicos do esmalte de dentes decíduos após condicionamento com ácido fosfórico a 36% ou com um agente condicionador não lavável. Foram selecionados 10 dentes decíduos anteriores esfoliados naturalmente. As amostras sofreram limpeza coronária com pasta de pedra-pomes e água, em baixa-velocidade. O condicionamento foi realizado no esmalte da face vestibular. Os espécimes foram divididos em dois grupos: G1 (n=10): condicionamento com ácido fosfórico a 36% na forma de gel - Conditioner 36 (Dentsply) durante 20 segundos, seguidos de lavagem com água durante 15 segundos; G2 (n=10): condicionamento com NRC - Non Rinse Conditioner (Dentsply) durante 20 segundos, seguidos de secagem com ar durante 15 segundos. As amostras foram desidratadas, montadas em bases metálicas e cobertas com ouro para análise ao microscópio eletrônico de varredura (Jeol JSM 6.100). A análise da eletromicrografias revelou que ambos os agentes condicionadores foram efetivos para condicionar o esmalte de dentes decíduos, causando microporosidades mas com melhor resultado quando utilizou-se o ácido fosfórico a 36% na forma de gel.