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Shear bond strength between different materials bonded with two resin cements

Muller, Katia; do Nascimento, Cassio; Miani, Paola K.; Goncalves, Mariane; de Albuquerque, Rubens Ferreira, Jr.
Fonte: WILEY-BLACKWELL; HOBOKEN Publicador: WILEY-BLACKWELL; HOBOKEN
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
96.44%
Background: The aim of this study was to compare the shear bond strength between Ni-Cr alloy specimens bonded to air-abraded Ni-Cr, bur-abraded Ni-Cr, etched ceramic and etched enamel substrates using the resin cements RelyX ARC or Enforce. Materials and methods: Ni-Cr specimens were made and sandblasted with Al2O3 airborne-particles. Disc-shaped patterns were made for each of the four experimental substrates: Ni-Cr treated with Al2O3 airborne-particles, Ni-Cr treated with diamond bur abrasion, etched enamel and etched ceramic. Results: Significant differences in shear bond strength were found between the different materials and luting agents evaluated. The Ni-Cr alloy cylinders bonded to Ni-Cr surfaces sandblasted with 50 lm Al2O3 particles and bonded with Enforce achieved the highest bond strength when compared with other substrates (28.9 MPa, p < 0.05). Bur-abraded metal discs had lowest values, regardless the cement used (2.9 and 6.9 MPa for RelyX and Enforce, respectively). Etched enamel and etched ceramic had similar shear bond strengths within cement groups and performed better when RelyX was used. Conclusions: Bonding Ni-Cr to Ni-Cr and ceramic may result in similar and higher bond strength when compared to Ni-Cr/enamel bonding. For metal/metal bonding...

"Distribuição de tensões em testes de cisalhamento e micro-cisalhamento mediante análise de elementos finitos" ; A finite element stress analysis of shear and micro-shear bond strength tests

Placido, Eliane
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 23/06/2006 PT
Relevância na Pesquisa
96.46%
Os objetivos deste estudo foram comparar, através de análise de elementos finitos, a distribuição de tensões em modelos que representam arranjos experimentais nor-malmente utilizados em testes de cisalhamento e micro-cisalhamento, verificar a tendência de variar o local de início e o modo de fratura em função de mudanças nos parâmetros dos ensaios e analisar a influência de dois modos de fixação do substrato sobre a concentração de tensões. Os modelos bidimensionais em estado plano de deformações representaram o compósito (híbrido ou flow) aderido à dentina através de uma camada de adesivo de 50 μm. Duas condições de fixação da dentina foram estabelecidas: na primeira (mais rígida), os deslocamentos foram restritos em todas as direções nos nós das arestas que representam as três superfícies livres de adesão e na segunda, a restrição foi colocada apenas na parte posterior da dentina. Foi aplicado um carregamento pontual a várias distâncias da interface dentina-adesivo, de modo a obter um tensão nominal constante de 4MPa. Foram analisadas as tensões máximas de tração e cisalhamento, a distribuição das tensões ao longo dos nós da interface dentina-adesivo e os vetores de tensão máxima principal...

Resistência ao cisalhamento de selante associado a dois sistemas adesivos, após contaminação salivar: influência da fotopolimerização individual e simultânea; Shear bond strength of a pit-and-fissure sealant associated with two adhesive systems after salivary contamination: influence of individual and simultaneous light curing

Silva, Jaciara Miranda Gomes da
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 06/08/2007 PT
Relevância na Pesquisa
96.46%
Este trabalho teve por objetivo avaliar "in vitro" a resistência ao cisalhamento de um selante resinoso (Fluroshield - F) em associação com um sistema adesivo total-etch (Adper Single Bond 2-SB) e um self-etching (Clearfil S3 Bond-S3) em condições de contaminação salivar, comparando dois protocolos de fotopolimerização: individual do sistema adesivo e, em seguida, do selante ou simultânea de ambos materiais conjuntamente. Superfícies mesiais e distais de 45 terceiros molares humanos hígidos foram incluídas e planificadas, o sítio de adesão delimitado (Ø 3mm) e os corpos-de-prova alocados aleatoriamente em 6 grupos experimentais (n=15), de acordo com o tratamento empregado: I- F aplicado sobre o esmalte condicionado com ácido fosfórico a 37% (controle). Os demais grupos foram contaminados com saliva (0,01ml por 10 s) e a seguir foram aplicados: II- SB e F fotopolimerizados separadamente; III- SB e F fotopolimerizados conjuntamente; IVS3 e F fotopolimerizados separadamente; V- S3 e F fotopolimerizados simultaneamente; VI- F aplicado sem associação com adesivos sobre o esmalte condicionado e contaminado. A seguir, um cilindro de selante foi confeccionado com o auxílio de uma mesa metálica e de matriz de teflon bipartida sobre o sítio de adesão. Após armazenamento durante 24 horas a 37°C em água destilada...

A importância de alguns adesivos dentais e de vários tratamentos da superfície sobre a dentina humana in vitro. Análise da resistência adesiva por micro-cisalhamento; The relevance of some dental adhesives and different surface instrumentations on human dentin (in vitro). Micro-shear bond strength analyses

Macedo, Manoel Roberto de Paula
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 05/12/2008 PT
Relevância na Pesquisa
96.48%
O objetivo deste trabalho foi estudar a ação sobre a dentina humana (in vitro) de vários tratamentos de superfície: Lixa, IADR-GM, CVDt e CVDi e de alguns adesivos dentais: Adper Sigle Bond 2 (SB), Clearfil SE Bond (CF) e Adper Prompt L-Pop (PL) avaliando: rugosidade e resistência adesiva por micro-cisalhamento. Foram utilizados 72 terceiros molares hígidos que foram divididos ao meio. As superfícies oclusais das 144 metades dentais foram removidas e padronizadas com Lixa #600. Após receberem os tratamentos de superfície citados, foi avaliada a rugosidade média superficial (Ra) da dentina. Em seguida realizou-se a hibridização e a confecção dos cilindros de resina composta (RC) para finalizar o preparo dos corpos de prova (cps). Após armazenagem de 24h em água destilada a 370C realizou-se o teste de micro-cisalhamento com velocidade de deslocamento de 1mm/min. Os resultados foram submetidos a testes de analise estatística (ANOVA) onde foi comprovado que a menor Ra foi encontrada nas superfícies instrumentadas com Lixa #600 seguida pelo CVDi, IADR-GM que apresentaram rugosidade intermediaria e se igualaram e pelo CVDt que produziram as superfícies mais rugosas. Já para o tratamento de superfície, o CVDi foi que apontou os piores valores de resistência de adesão que com Lixa e IADR-GM. Nos resultados para os adesivos...

Ação triboquímica do ciclo mastigatório na resistência ao cisalhamento de resinas compostas; Tribocorrosion effects of masticatory cycle on the composite resins shear bond strength

Contente, Marta Maria Martins Giamatei
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 07/10/2013 PT
Relevância na Pesquisa
96.46%
Este trabalho avaliou in vitro a ação de estímulos triboquímicos que simulam o ciclo mastigatório na resistência ao cisalhamento de duas resinas compostas Filtek P90®- 3M ESPE (P) e Z250®-3M ESPE (Z) com e sem presença de contaminação salivar, assim como a liberação de íons e a qualidade e a quantidade do desgaste produzido. A amostra foi composta por 12 grupos experimentais (n=5): P1 e Z1, sem contaminação/contra dente decíduo; P2 e Z2, com contaminação/contra dente decíduo; P3 e Z3, sem contaminação/contra dente permanente; P4 e Z4, com contaminação/contra dente permanente; P5 e Z5 sem contaminação (controle); P6 e Z6 com contaminação (controle). Ensaios de tribocorrosão foram efetuados na configuração pino-placa de deslizamento linear alternativo, na presença da solução de saliva artificial, carga de 3N e frequência de 1Hz, totalizando 900 ciclos de desgaste durante 15 minutos. As pistas de desgaste foram caracterizadas por MEV, EDX e XRD e o volume de desgaste por análise da variação de massa. A MEV demonstrou que os grupos Z apresentaram maior quantidade de desgaste quando comparados aos grupos P e que os antagonistas de dente permanente apresentaram maior quantidade de resíduos do material desgastado que os antagonistas em dentes decíduos. A análise por XRD não apresentou variação na caracterização de nenhuma das amostras quando se comparou os espécimes antes e após a realização dos experimentos. Na análise por EDX observou-se picos correspondentes aos elementos Ítrio e Silício para os antagonistas dos grupos P e de Zircônia para os dos grupos Z. Os dados obtidos pelo ensaio de nanoendentação não apresentaram diferença estatisticamente significante para nenhum dos grupos estudados (ANOVA e Teste de Duncan p≤0...

Shear bond strength of metallic brackets : influence of saliva contamination

Retamoso, Luciana Borges; Collares, Fabrício Mezzomo; Ferreira, Eduardo Silveira; Samuel, Susana Maria Werner
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
ENG
Relevância na Pesquisa
96.47%
Objective: To evaluate the influence of saliva contamination on shear bond strength and the bond failure pattern of 3 adhesive systems (Transbond XT, AdheSE and Xeno III) on orthodontic metallic brackets bonded to human enamel. Material and Methods: Seventy-two permanent human molars were cut longitudinally in a mesiodistal direction, producing seventy-two specimens randomly divided into six groups. Each system was tested under 2 different enamel conditions: no contamination and contaminated with saliva. In T, A and X groups, the adhesive systems were applied to the enamel surface in accordance with manufacturer’s instructions. In TS, AS and XS groups, saliva was applied to enamel surface followed by adhesive system application. The samples were stored in distilled water at 37ºC for 24 h, and then tested for shear bond strength in a universal testing machine (Emic, DL 2000) running at a crosshead speed of 1 mm/min. After bond failure, the enamel surfaces were observed under an optical microscope at 40x magnification. Results: The control and contaminated groups showed no significant difference in shear bond strength for the same adhesive system. However, shear bond strength of T group (17.03±4.91) was significantly higher than that of AS (8.58±1.73) and XS (10.39±4.06) groups (p<0.05). Regarding the bond failure pattern...

Influência do tratamento de superfície na resistência de união por cisalhamento de um cerômero indireto; Surface treatment effect on shear bond strength of an indirect ceromer

Ferreira, Fábio Mossmann; Braga, Carlos; Klein Júnior, Celso Afonso; Veleda, Bárbara Borges; Erhardt, Maria Carolina Guilherme; Coelho de Souza, Fábio Herrmann
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
POR
Relevância na Pesquisa
96.39%
Objetivo: o presente estudo realizou uma análise comparativa da resistência ao cisalhamento em dentina após diferentes tratamentos de superfície do cerômero BelleGlass HP (Kerr). Materiais e métodos: para isso, trinta molares humanos tiveram suas faces livres desgastadas até expor a superfície dentinária, nas quais foram cimentados os corpos de prova (belleGlass HP) com cimento resinoso (RelyX ARC, 3M ESPE), com três tratamentos de superfície: grupo 1 (controle): sem tratamento de superfície; grupo 2: condicionamento com ácido fluorídrico 10%; e grupo 3: jateamento com óxido de alumínio com granulação de 50μm. Os espécimes foram avaliados em relação à resistência de união por cisalhamento, com velocidade de 1,0mm/min. Os dados foram analisados estatisticamente através dos testes ANOVA e Tukey, com nível de significância de 5%. Resultados: como resultado, obteve-se diferenças estatisticamente significativas (P=0,002) entre o grupo controle e o grupo 3. Conclusão: concluiu-se que o tipo de tratamento de superfície do cerômero belleGlass influenciou a resistência de união dos espécimes cimentados, sendo o jateamento com óxido de alumínio o que apresentou melhor desempenho.; Aim: The present study showed a comparative analysis of shear bond strength of a ceromer after different surface treatments. Material and methods: For that...

Shear bond strength of resin cement bonded to alumina ceramic after treatment by aluminum oxide sandblasting or silica coating

Passos, Sheila Pestana; Valandro, Luiz Felipe; Bottino, Marco Antonio; Santos, Maria Jacinta Moraes Coelho; Santos Jr., Gildo Coelho
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 561-565
ENG
Relevância na Pesquisa
96.45%
Purpose: To evaluate the shear bond strength and bond durability between a dual-cured resin cement (RC) and a high alumina ceramic (In-Ceram Alumina), subjected to two surface treatments. Materials and Methods: Forty disc-shaped specimens (sp) (4-mm diameter, 5-mm thick) were fabricated from In-Ceram Alumina and divided into two groups (n = 20) in accordance with surface treatment: (1) sandblasting by aluminum oxide particles (50 μm Al 2O 3) (SB) and (2) silica coating (30 μm SiO x) using the CoJet system (SC). After the 40 sp were bonded to the dual-cured RC, they were stored in distilled water at 37°C for 24 hours. After this period, the sp from each group were divided into two conditions of storage (n = 10): (a) 24 h-shear bond test 24 hours after cementation; (b) Aging-thermocycling (TC) (12,000 times, 5 to 55°C) and water storage (150 days). The shear test was performed in a universal test machine (1 mm/min). Results: ANOVA and Tukey (5%) tests noted no statistically significant difference in the bond strength values between the two surface treatments (p= 0.7897). The bond strengths (MPa) for both surface treatments reduced significantly after aging (SB-24: 8.2 ± 4.6; SB-Aging: 3.7 ± 2.5; SC-24: 8.6 ± 2.2; SC-Aging: 3.5 ± 3.1). Conclusion: Surface conditioning using airborne particle abrasion with either 50 μm alumina or 30 μm silica particles exhibited similar bond strength values and decreased after long-term TC and water storage for both methods. © 2011 by The American College of Prosthodontists.

Shear bond strength of enamel surface treated with air-abrasive system

Borsatto,Maria Cristina; Catirse,Alma Blásida Elisaur Benitez; Palma Dibb,Regina Guenka; Nascimento,Telma Nunes do; Rocha,Renata Andréa Salvitti de Sá; Corona,Silmara Aparecida Milori
Fonte: Fundação Odontológica de Ribeirão Preto Publicador: Fundação Odontológica de Ribeirão Preto
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2002 EN
Relevância na Pesquisa
96.44%
The aim of this study was to evaluate the shear bond strength of a composite resin to dental enamel, using three different surface treatments. Fifteen sound third molars were randomly assigned to three groups. The mesial and distal surfaces were flattened and covered using adhesive tape with a central orifice delimiting the adhesion area (7.07 mm²). Group I, the enamel surface was conditioned with 37% phosphoric acid for 15 s; group II, the surface was treated using air abrasion with aluminum oxide; group III, the enamel surface was treated using an association of air abrasion with aluminum oxide and 37% phosphoric acid. The Single Bond (3M) adhesive system was applied and a Teflon matrix was placed and filled with composite resin Z-100 (3M) and light-cured. The shear bond strength test was performed with a universal testing machine. The acid etching technique and air abrasion with aluminum oxide associated with acid etching had the highest shear bond strength values. Data were subjected to statistical analysis using ANOVA and the Tukey test, and no statistically significant difference in shear bond strength was observed between group I (12.49 ± 2.85 MPa) and group III (12.59 ± 2.68 MPa). In contrast, both groups had statistically better shear bond strengths compared to group II (0.29 ± 0.56 MPa; p<0.05). Air abrasion with aluminum oxide does not substitute acid etching. The association of these methods to obtain adequate adhesion to the substrate is necessary.

Shear bond strength of dental porcelains to nickel-chromium alloys

Prado,Ricardo Alves do; Panzeri,Heitor; Fernandes Neto,Alfredo Julio; Neves,Flávio Domingues das; Silva,Marlete Ribeiro da; Mendonça,Gustavo
Fonte: Fundação Odontológica de Ribeirão Preto Publicador: Fundação Odontológica de Ribeirão Preto
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2005 EN
Relevância na Pesquisa
96.46%
The continuous technological advance and increasing availability of new base metal alloys and ceramic systems in the market, coupled to the demands of daily clinical practice, have made the constant evaluation of the bond strength of metal/porcelain combinations necessary. This study evaluated the metal/porcelain shear bond strength of three ceramic systems (Duceram, Williams and Noritake) in combination with three nickel-chromium (Ni-Cr) alloys (Durabond, Verabond and Viron). Thirty cast cylinder specimens (15 mm high; 6 mm in diameter) were obtained for each alloy, in a way that 10 specimens of each alloy were tested with each porcelain. Bond strength was measured with an Emic screw-driven mechanical testing machine by applying parallel shear forces to the specimens until fracture. Shear strength was calculated using the ratio of the force applied to a demarcated area of the opaque layer. Mann-Whitney U test was used for statistical analysis of the alloy/ceramic combinations (p<0.05). Viron/Noritake had the highest shear bond sregnth means (32.93 MPa), while Verabond/Duceram (16.31 MPa) presented the lowest means. Viron/Noritake differed statistically from other combinations (p<0.05). Viron/Duceram had statistically significant higher bond strengths than Verabond/Duceram...

Influence of surface treatment on shear bond strength of orthodontic brackets

Brunharo,Ione Helena Vieira Portella; Fernandes,Daniel Jogaib; Miranda,Mauro Sayão de; Artese,Flavia
Fonte: Dental Press International Publicador: Dental Press International
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2013 EN
Relevância na Pesquisa
96.44%
INTRODUCTION: The shear bond strength of orthodontic brackets bonded to micro-hybrid and micro-particulate resins under different surface treatment methods was assessed. METHODS: Two hundred and eighty test samples were divided into 28 groups (n = 10), where 140 specimens were filled with Durafill micro-particulate resin and 140 with Charisma composite. In 140 samples, a coupling agent (silane) was applied. The surface treatment methods were: Phosphoric and hydrofluoric acid etching, sodium bicarbonate and aluminum oxide blasting, stone and burs. A Universal Instron Machine was used to apply an occlusal shear force directly to the resin composite bracket surface at a speed of 0.5 mm/min. The means were compared using analysis of variance and multivariate regression to assess the interaction between composites and surface treatment methods. RESULTS: Means and standard deviations for the groups were: Sodium bicarbonate jet 11.27±2.78; burs 9.26±3.01; stone 7.95±3.67; aluminum oxide blasting 7.04±3.21; phosphoric acid 5.82±1.90; hydrofluoric acid 4.54±2.87, and without treatment 2.75±1.49. An increase of 1.94 MPa in shear bond strength was seen in Charisma groups. Silane agent application reduced the Charisma shear bond strength by 0.68 Mpa...

The effect of thermal cycling on the shear bond strength of porcelain/Ti-6Al-4V interfaces

Sendao, Isabel A.; Alves, Alexandra C.; Galo, Rodrigo; Toptan, Fatih; Silva, Filipe S.; Ariza, Edith
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 156-163
ENG
Relevância na Pesquisa
96.39%
The aim of the study was to evaluate the effect of thermal cycling on the shear bond strength of the porcelain/Ti-6Al-4V interfaces prepared by two different processing routes and metallic surface conditions. Polished and SiO2 particle abraded Ti-6Al-4V alloy and Triceram bonder porcelain were used to produce the interfaces. Porcelain-to-metal specimens were processed by conventional furnace firing and hot pressing. Thermal cycling was performed in Fusayama's artificial saliva for 5000 cycles between 5 +/- 1 and 60 +/- 2 degrees C. After thermal cycling, shear bond tests were carried out by using a custom-made stainless steel apparatus. The results were analyzed using t-Student test and non-parametric Kruskal-Wallis test (p<0.01). Most of the polished-fired specimens were fractured during thermal cycling; thus, it was not possible to obtain the shear bond strength results for this group. Sandblasted-fired, polished-hot pressed, and sandblasted-hot pressed specimens presented the shear bond strength values of 76.2 +/- 15.9, 52.2 +/- 23.6, and 59.9 +/- 22.0 MPa, respectively. Statistical analysis indicated that thermal cycling affected the polished specimens processed by firing, whereas a significant difference was not observed on the other groups. (C) 2015 Elsevier Ltd. All rights reserved.

Shear bond strength between Ni-Cr alloy bonded to a ceramic substrate

Nascimento, Cassio do; Miani, Paola Kirsten; Bezzon, Osvaldo Luiz; Goncalves, Mariane; Albuquerque Junior, Rubens Ferreira de
Fonte: WILEY-BLACKWELL; HOBOKEN Publicador: WILEY-BLACKWELL; HOBOKEN
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
96.41%
Shear bond strength between Ni-Cr alloy bonded to a ceramic substrate Introduction: The aim of this study was to evaluate the shear bond strength between a Ni-Cr alloy and a ceramic system submitted or not to thermocycling. Materials and methods: Forty-eight cylinder blocks of Ni-Cr with 3.0 mm diameter by 4.0 mm hight and 48 disc-shaped specimens (7.0 mm in diameter by 2.0 mm thick) composed of ceramic were prepared. The Ni-Cr cylinder blocks were randomised in two groups of 24 specimens each. One group was submitted to air-particle abrasion (sandblasting) with 50 mu m Al2O3 (0.4-0.7 MPa) during 20 s, and the other group was submitted to mechanical retentions with carbide burrs. Each group was subdivided into other two groups (n = 12), submitted or not to thermocycling (500 cycles, 5-55 degrees C). The cylinder blocks were bonded to the disc-shaped ceramic specimens under 10 N of load. The shear bond strengths (MPa) were measured using a universal testing machine at a cross head speed of 0.5 mm/min and 200 kgf of load. The data were submitted to statistical analysis (ANOVA and Tukey's test). Results: The air-particle abrasion group exhibited significantly higher shear bond strength when compared to drilled group (p < 0.05). Conclusions: Thermocycling decreased significantly the bond strengths for all groups tested.

Shear bond strength of metallic brackets: influence of saliva contamination

Retamoso,Luciana Borges; Collares,Fabrício Mezzomo; Ferreira,Eduardo Silveira; Samuel,Susana Maria Werner
Fonte: Faculdade De Odontologia De Bauru - USP Publicador: Faculdade De Odontologia De Bauru - USP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2009 EN
Relevância na Pesquisa
96.47%
OBJECTIVE: To evaluate the influence of saliva contamination on shear bond strength and the bond failure pattern of 3 adhesive systems (Transbond XT, AdheSE and Xeno III) on orthodontic metallic brackets bonded to human enamel. MATERIAL AND METHODS: Seventy-two permanent human molars were cut longitudinally in a mesiodistal direction, producing seventy-two specimens randomly divided into six groups. Each system was tested under 2 different enamel conditions: no contamination and contaminated with saliva. In T, A and X groups, the adhesive systems were applied to the enamel surface in accordance with manufacturer's instructions. In TS, AS and XS groups, saliva was applied to enamel surface followed by adhesive system application. The samples were stored in distilled water at 37ºC for 24 h, and then tested for shear bond strength in a universal testing machine (Emic, DL 2000) running at a crosshead speed of 1 mm/min. After bond failure, the enamel surfaces were observed under an optical microscope at 40x magnification. RESULTS: The control and contaminated groups showed no significant difference in shear bond strength for the same adhesive system. However, shear bond strength of T group (17.03±4.91) was significantly higher than that of AS (8.58±1.73) and XS (10.39±4.06) groups (p<0.05). Regarding the bond failure pattern...

Shear bond strength of acetone-based one-bottle adhesive systems

Lopes,Guilherme Carpena; Cardoso,Paula C.; Vieira,Luiz Clovis Cardoso; Baratieri,Luiz N.; Rampinelli,Karina; Costa,Gisele
Fonte: Fundação Odontológica de Ribeirão Preto Publicador: Fundação Odontológica de Ribeirão Preto
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2006 EN
Relevância na Pesquisa
96.44%
The aim of this study was to assess the shear bond strength of four acetone-based one-bottle adhesive systems to enamel and dentin, and compare to that of an ethanol-based system used as control. Fifty human molars were bisected mesiodistally and the buccal and lingual surfaces were embedded in acrylic resin using PVC cylinders. The buccal surfaces were ground to obtain flat dentin surfaces, while the lingual surfaces were ground to obtain flat enamel surfaces. All specimens were polished up to 600-grit sandpapers and randomly assigned to 5 groups (n=20; 10 dentin specimens and 10 enamel specimens), according to the adhesive system used: One-Step (Bisco); Gluma One Bond (Heraeus Kulzer); Solobond M (Voco); TenureQuik w/F (Den-Mat) and OptiBond Solo Plus (Kerr) (control). Each adhesive system was applied according to the manufacturers' instructions. The respective proprietary hybrid composite was applied in a gelatin capsule (d=4.3mm) and light-cured for 40 s. The specimens were tested in shear strength with an Instron machine at a crosshead speed of 5 mm/min. Bond strengths means were analyzed statistically by one-way ANOVA and Duncan's post-hoc (p£0.05). Shear bond strength means (MPa) (±SD) to enamel and dentin were: Enamel: One-Step=11.3(±4.9); Gluma One Bond=16.3(±10.1); Solobond M=18.9(±4.5); TenureQuik w/F=18.7(±4.5) and OptiBond Solo Plus=16.4(±3.9); Dentin: One-Step=6.4(±2.8); Gluma One Bond=3.0(±3.4); Solobond M=10.6(±4.9); TenureQuik w/F=7.8(±3.9) and OptiBond Solo Plus=15.1(±8.9). In enamel...

Effect of light-curing units in shear bond strength of metallic brackets: an in vitro study

Retamoso,Luciana Borges; Onofre,Niége Michelle Lazzari; Hann,Luciane; Marchioro,Ernani Menezes
Fonte: Faculdade De Odontologia De Bauru - USP Publicador: Faculdade De Odontologia De Bauru - USP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2010 EN
Relevância na Pesquisa
96.43%
OBJECTIVES: To determine the influence of the light curing units on the shear bond strength of orthodontic brackets. MATERIAL AND METHODS: Seventy-two premolars were divided into six groups (n=12): Group I: brackets bonded with Transbond and polymerization with halogen light; Group II: Transbond and LED; Group III: Fuji Ortho and halogen light; Group IV: Fuji Ortho and LED; Group V: Fuji Ortho, without acid and halogen light; Group VI: Fuji Ortho, without acid and LED. The groups were tested to shear strength in a universal testing machine at a crosshead speed of 0.5 mm/min. Data were analyzed statistically by ANOVA and Tukey's test. RESULTS: The composite resin presented higher shear bond strength than the resin-modified glass ionomer cement (p<0.05). The halogen light and LED sources produced similar shear bond strength (p>0.05). CONCLUSION: The shear bond strength was influenced by the material but not by the light-curing unit. The use of LED reduced the experimental time by approximately 60%, with the same curing efficiency.

Shear bond strength of metallic brackets: influence of saliva contamination

Retamoso, Luciana Borges; Collares, Fabrício Mezzomo; Ferreira, Eduardo Silveira; Samuel, Susana Maria Werner
Fonte: Universidade de São Paulo. Faculdade de Odontologia de Bauru Publicador: Universidade de São Paulo. Faculdade de Odontologia de Bauru
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; Formato: application/pdf
Publicado em 01/06/2009 ENG
Relevância na Pesquisa
96.43%
OBJECTIVE: To evaluate the influence of saliva contamination on shear bond strength and the bond failure pattern of 3 adhesive systems (Transbond XT, AdheSE and Xeno III) on orthodontic metallic brackets bonded to human enamel. MATERIAL AND METHODS: Seventy-two permanent human molars were cut longitudinally in a mesiodistal direction, producing seventy-two specimens randomly divided into six groups. Each system was tested under 2 different enamel conditions: no contamination and contaminated with saliva. In T, A and X groups, the adhesive systems were applied to the enamel surface in accordance with manufacturer's instructions. In TS, AS and XS groups, saliva was applied to enamel surface followed by adhesive system application. The samples were stored in distilled water at 37ºC for 24 h, and then tested for shear bond strength in a universal testing machine (Emic, DL 2000) running at a crosshead speed of 1 mm/min. After bond failure, the enamel surfaces were observed under an optical microscope at 40x magnification. RESULTS: The control and contaminated groups showed no significant difference in shear bond strength for the same adhesive system. However, shear bond strength of T group (17.03±4.91) was significantly higher than that of AS (8.58±1.73) and XS (10.39±4.06) groups (p

Shear bond strength test using different loading conditions – a finite element analysis;

Braz, Rodivan; Sinhoreti, Mário Alexandre Coelho; Spazzin, Aloísio Oro; Loretto, Sandro Cordeiro; Lyra, Arine Maria Viveros de Castro; Meira Júnior, Agenor Dias de
Fonte: UNICAMP/FOP Publicador: UNICAMP/FOP
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; Formato: application/pdf
Publicado em 16/11/2015 ENG
Relevância na Pesquisa
96.4%
Aim: This study evaluated the stress distribution at the bond interface during shear bond strength testing for three loading conditions. Methods: A three-dimensional model was created of a specimen for evaluation by the shear bond strength test, using three cylindrical volumes representing the dentin, adhesive system and composite resin. A linear analysis was performed to calculate the stress distribution at the dentin-adhesive interface. Three models simulating different loading conditions were prepared: chisel, orthodontic-looped wire and stainless steel tape. Results: Chisel presented severe stress concentrations near the loading site (-10681 to 637 MPa). Wire presented stress concentrations along the radial loading axis (-382 to 216 MPa). Tape presented more uniform stress distribution (-83 to 21 MPa). Conclusions: The loading with stainless steel tape allowed more uniform stress distribution at the bond interface, and was a more reliable way to evaluate the bond with regard to the aim of the shear bond strength test.;

; Antioxidant effect on the shear bond strength of composite to bleached bovine dentin

Tabatabaei, Masoomeh Hasani; Aram, Sakineh; Nojoumian, Atefeh; Mirzaei, Mansooreh
Fonte: UNICAMP/FOP Publicador: UNICAMP/FOP
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; Formato: application/pdf
Publicado em 12/11/2015 ENG
Relevância na Pesquisa
96.42%
; Several studies have shown that compromised bonding to bleached enamel can be reversed with antioxidants. Aim: The aim of this study was investigate the effect of the antioxidant treatment on the micro-shear bond strength of a composite resin with a clinically acceptable antioxidant usage time taken into account. Methods: Using in vitro techniques, the effect of the antioxidant sodium ascorbate (SA) was evaluated on the micro-shear bond strength of a hybrid composite resin (Tetric® A2 Ivoclar Vivadent) to dentin, which was bleached with 35% carbamide peroxide (Opalescence Quick, Ultradent Products Inc). Thirty-five intact flat buccal dentin surfaces from bovine incisors were randomly assigned to five groups which were subjected to the following treatment protocols: group 1, bleached for 45 min and bonded immediately afterwards; groups 2 and 3, bleached and then treated with 10% SA for 10 and 5 min before bonding, respectively; group 4, stored in distilled water for seven days after bleaching and before bonding; group 5, received no bleaching or antioxidant treatment. After the bonding procedure, specimens were subjected to a micro-shear bonding test. Data were analyzed by ANOVA and a post-hoc Tukey’s test. Results: One-way ANOVA revealed significant differences in bond strength among the five groups. Conclusions: It was found that the shear bond strength was reduced by carbamide peroxide bleaching...

; Shear bond strength of adhesive systems to saliva-contaminated dentin

Sálvio, Luciana Andrea; Sinhoreti, Mário Alexandre Coelho; Correr Sobrinho, Lourenço; Consani, Simonides; Konno, Alysson Noriyuki Kajishima
Fonte: UNICAMP/FOP Publicador: UNICAMP/FOP
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ;
Publicado em 13/11/2015 ENG
Relevância na Pesquisa
96.44%
; This study evaluated the shear bond strength of two adhesive systems: Scotchbond Multi-Purpose (SBMP) and Clearfil Liner Bond 2V (CLB2V) on different dentin surface conditions. Bovine incisors were collected and prepared according to the ISO’s (TR 11405) directions. The samples were divided into nine groups (n=10): 1- SBMP control group (without contamination); 2-SBMP: saliva contamination after priming; 3- SBMP: saliva contamination after bond application; 4-SBMP: saliva contamination after acid etching; 5-SBMP: as group 4 with re-etching after saliva contamination; 6-CLB2V control group (without contamination); 7-CLB2V: saliva contamination after priming; 8-CLB2V: saliva contamination after bond application; and, 9-CLB2V: saliva contamination before priming. After the storage period in water at 37o C, the samples were tested with an Instron testing machine, at crosshead speed of 0.5mm/min. The results were submitted to ANOVA (one way) and Tukey’s test at 5% significance level. For SBMP groups, the mean shear bond strengths were: 1 - 4.8 MPa, 2 - 5.0 MPa, 3 - 5.2 MPa, 4 - 6.6 MPa and 5 - 4.2 MPa. There was no statistical difference among groups tested. For CLB2V groups 6, 8, 9, the mean shear bond strengths were 8.0 MPa, 6.9 MPa and 8.8 MPa respectively and demonstrated no statistical differences. Group 7 (4.7 MPa) differed from all other groups except 8. Slight salivary contamination does not influence the shear bond strength of SBMP during any stage and slight salivary contamination influences the shear bond strength of CLB2V after priming step.