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Microtensile Bond Strength of Glass Fiber Posts Cemented with Self-adhesive and Self-etching Resin Cements

ZAITTER, Suellen; SOUSA-NETO, Manoel D.; ROPERTO, Renato C.; SILVA-SOUSA, Yara T. C.; EL-MOWAFY, Omar
Fonte: QUINTESSENCE PUBLISHING CO INC Publicador: QUINTESSENCE PUBLISHING CO INC
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
66.39%
Purpose: To evaluate the bond strength of glass fiber posts to intraradicular dentin when cemented with self-etching and self-adhesive resin cements. Materials and Methods: Forty-eight single-rooted human teeth were decoronated, endodontically treated, post-space prepared and divided into 8 groups (n = 6). The glass fiber posts used were: Exacto (EA) (Angelus) and everStick (ES) (StichTeck), which were cemented with two self-adhesive resin cements: BisCem (BIS) (Bisco) and Rely-X Unicem (UNI) (3M/ESPE), and two self-etching resin cements: Esthetic Cementing System NAC100 (NAC) (Kuraray) and Panavia-F (PAN) (Kuraray). Specimens were thermocycled between 5 degrees C and 55 degrees C for 1000 cycles and stored in water at 37 degrees C for 1 month. Four 1-mm-thick (in cross section) rods were obtained from the cervical region of the roots. Specimens were then subjected to microtensile testing in a special machine (BISCO; Schaumburg, IL, USA) at a crosshead speed of 0.5 mm/min. Microtensile bond strength (mu TBS) data were analyzed with two-way ANOVA and Tukey`s tests. Results: Means (and SD) of mu TBS (MPa) were: EA/PAN: 10.3 (4.1), EA/NAC: 14 (5.1) EA/BIS: 16.4 (4.8), EA/UNI: 19.8 (5.1), ES/PAN: 25.9 (6.1), ES/NAC: 29.1 (7), ES/BIS: 28.9 (6)...

"Estudo teórico e experimental de vigas de madeira laminada colada reforçadas com fibra de vidro" ; Theoretical and experimental study of glulam beam reinforced with glass fiber

Fiorelli, Juliano
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 25/04/2005 PT
Relevância na Pesquisa
66.34%
O uso de madeira laminada colada (MLC) em países da América do Norte e Europa é bastante difundido. No Brasil, apesar da técnica existir desde o século XX, a sua utilização é incipiente em relação à possibilidade de utilização desse produto. O desenvolvimento de produtos a partir de lâminas de madeira com pequenas dimensões se deve à necessidade de se eliminar defeitos nas peças estruturais, tais como nó e medula, os quais reduzem significativamente as características de resistência e elasticidade da peça, em comparação com a madeira sã. O aumento da resistência e da rigidez da viga de MLC pode ser conseguido por meio da classificação das lâminas, seguida de uma disposição adequada das mesmas. Outra maneira de se obter um aumento nas propriedades de rigidez e de resistência de elementos estruturais de MLC é a utilização de polímeros reforçados com fibras (PRF) na região mais tracionada da viga. Esta providência, além de melhorar as propriedades mecânicas do elemento estrutural, aumenta a confiabilidade em relação ao modo de ruptura. Dentro deste escopo, este trabalho procura estabelecer critérios para fabricação de vigas retas de MLC, sem e com reforço de fibras de vidro, a partir de informações obtidas na revisão bibliográfica...

Influência de três sistemas adesivos na resistência à extrusão de pinos de fibras de vidro fixados com um cimento resinoso; Influence of three adhesives systems on the extrusion strength of glass fiber posts fixed by resin cements

Raineri, Juliana Cefaly
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 03/05/2006 PT
Relevância na Pesquisa
66.39%
Com o intuito de elevar os valores de resistência à fratura dos dentes que sofreram tratamento endodôntico, várias técnicas restauradoras têm sido desenvolvidas. Atualmente os sistemas de pinos de fibras de carbono e de vidro são os dispositivos mais utilizados, devido às suas vantagens de possuírem módulo de elasticidade próximo ao da dentina, o que causa menor estresse e conseqüentemente menor quantidade de fraturas radiculares, além de não necessitarem da fase laboratorial. A escolha do cimento utilizado para a cimentação desses pinos, tem grande importância e o advento dos cimentos resinosos e dos sistemas adesivos que com eles podem ser empregados, representam uma grande evolução em razão das possibilidades de se obter retenções micromecânicas no interior dos condutos. Assim, o objetivo deste estudo foi avaliar a resistência à extrusão de pinos de fibras de vidro cimentados com cimento resinoso Rely X ARC com a aplicação de três diferentes sistemas adesivos: Scotchbond, Single bond e Adper Prompt LPop. Após a cimentação os espécimes foram seccionados em duas regiões, apical e cervical, que constituía cada uma um corpo de prova. Para possibilitar a realização do teste de extrusão, utilizou-se um dispositivo de aço inoxidável que estabilizava o corpo de prova. Este dispositivo tinha um orifício central que permitia o deslocamento do pino ou do cimento...

Compósitos de PVC reforçados com fibra de vidro: uso de técnicas de processamento convencionais da indústria brasileira.; Glass fiber reinforced PVC composites: use of conventional processing techniques currently employed in the Brazilian industry.

Feltran, Murilo de Barros
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 15/02/2008 PT
Relevância na Pesquisa
56.54%
Este trabalho apresenta o estudo da incorporação de fibra de vidro curta em composto rígido de poli(cloreto de vinila) - PVC - por meio de equipamentos e técnicas de processamento convencionais da indústria brasileira. Foram avaliadas as influências de: a) tamanho de fibra de vidro (tipo E), b) dosagem de fibra de vidro, c) dosagem de dióxido de titânio (TiO2) e d) a temperatura de processamento nas propriedades físicas, térmicas, mecânicas e na adesão entre matriz polimérica e fibra de vidro (analisada por Microscopia Eletrônica de Varredura). O custo-benefício dos compósitos foi calculado por meio de Índices de Mérito para os modos de carregamento mecânico encontrados nos tubos pressurizados para água fria (Cilindro com Pressão Interna) e perfis rígidos utilizados em construção civil (Barra em Flexão), dado o grande uso de PVC nestas aplicações. Entre os resultados obtidos, destaca-se o aumento de 45% no módulo de elasticidade para os compósitos com 20% de fibra de vidro moída que, para algumas aplicações, pode apresentar uma relação custo-benefício bastante favorável.; This work presents the impact of the short glass fiber incorporation in rigid PVC compound through conventional processing techniques currently employed in the Brazilian industry. It were studied the influences of a) glass fiber geometry (E type)...

Preparation and characterization of ramie-glass fiber reinforced polymer matrix hybrid composites

Romanzini, Daiane; Ornaghi Junior, Heitor Luiz; Amico, Sandro Campos; Zattera, Ademir José
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
66.55%
The use of ramie fibers as reinforcement in hybrid composites is justified considering their satisfactory mechanical properties if compared with other natural fibers. This study aims to verify changes in chemical composition and thermal stability of the ramie fibers after washing with distilled water. One additional goal is to study glass fiber and washed ramie fiber composites focusing on the effect of varying both the fiber length (25, 35, 45 and 55 mm) and the fiber composition. The overall fiber loading was maintained constant (21 vol.%). Based on the results obtained, the washed ramie fiber may be considered as an alternative for the production of these composites. The higher flexural strength presented being observed for 45 mm fiber length composite, although this difference is not significant for lower glass fiber volume fractions: (0:100) and (25:75). Also, by increasing the relative volume fraction of glass fiber until an upper limit of 75%, higher flexural and impact properties were obtained.

Hybridization effect on the mechanical properties of curaua/glass fiber composites

Almeida Jr., José Humberto Santos; Amico, Sandro Campos; Botelho, Edson Cocchieri; Amado, Franco Dani Rico
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 492-497
ENG
Relevância na Pesquisa
56.53%
The aim of this paper was to evaluate the effect of hybridizing glass and curaua fibers on the mechanical properties of their composites. These composites were produced by hot compression molding, with distinct overall fiber volume fraction, being either pure curaua fiber, pure glass fiber or hybrid. The mechanical characterization was performed by tensile, flexural, short beam, Iosipescu and also nondestructive testing. From the obtained results, it was observed that the tensile strength and modulus increased with glass fiber incorporation and for higher overall fiber volume fraction (%Vf). The short beam strength increased up to %Vf of 30 vol.%, evidencing a maximum in terms of overall fiber/matrix interface and composite quality. Hybridization has been successfully applied to vegetable/synthetic fiber reinforced polyester composites in a way that the various properties responded satisfactorily to the incorporation of a third component. © 2013 Published by Elsevier Ltd. All rights reserved.

Model to predict shrinkage and ejection forces of injection moulded tubular parts of short glass fiber reinforced thermoplastics

Garcia, M. C. R.; Netto, A. C. S.; Pontes, A. J.
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em //2011 ENG
Relevância na Pesquisa
66.41%
This work presents a model to predict shrinkage and ejection forces for glass fiber reinforced thermoplastics of tubular geometry. This mathematical model was based in Jansen’s Model to predict shrinkage and residual stresses in fiber reinforced injection molded products and Pontes’s Model to predict ejection forces for tubular parts of pure PP. The model used the modified classical laminate theory applied to injection moulding and it uses the fiber orientation state, temperature and pressure field as input and which predicts the shrinkage and ejection forces. The fiber orientation state was determined experimentally and the temperature and pressure fields were obtained by MOLDFLOW simulations. The model to predict ejection forces considers also the fiber orientation state, friction coefficient between steel and polymer, elastic modulus of polymer, both in the ejection temperature and diametrical shrinkage. The model is validated by experimental results.

Impact properties of aluminium - glass fiber reinforced plastics sandwich panels

Periasamy,Mathivanan; Manickam,Balakrishnan; Hariharasubramanian,Krishnan
Fonte: ABM, ABC, ABPol Publicador: ABM, ABC, ABPol
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2012 EN
Relevância na Pesquisa
66.37%
Aluminium - glass fiber reinforced plastics (GFRP) sandwich panels are hybrid laminates consisting of GFRP bonded with thin aluminum sheets on either side. Such sandwich materials are increasingly used in airplane and automobile structures. Laminates with varying aluminium thickness fractions, fiber volume fractions and orientation in the layers of GFRP were fabricated by hand lay up method and evaluated for their impact performance by conducting drop weight tests under low velocity impacts. The impact energy required for initiating a crack in the outer aluminium layer as well as the energy required for perforation was recorded. The impact load-time history was also recorded to understand the failure behavior. The damage depth and the damage area were measured to evaluate the impact resistance. Optical photography and scanning electron micrographs were taken to visualize the crack and the damage zone. The bidirectional cross-ply hybrid laminate (CPHL) has been found to exhibit better impact performance and damage resistance than the unidirectional hybrid laminate (UDHL). Increase in aluminium thickness fraction (Al tf) and fiber volume fraction (Vf) resulted in an increase in the impact energy required for cracking and perforation. On an overall basis...

Preparation and characterization of ramie-glass fiber reinforced polymer matrix hybrid composites

Romanzini,Daiane; Ornaghi Junior,Heitor Luiz; Amico,Sandro Campos; Zattera,Ademir José
Fonte: ABM, ABC, ABPol Publicador: ABM, ABC, ABPol
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2012 EN
Relevância na Pesquisa
66.55%
The use of ramie fibers as reinforcement in hybrid composites is justified considering their satisfactory mechanical properties if compared with other natural fibers. This study aims to verify changes in chemical composition and thermal stability of the ramie fibers after washing with distilled water. One additional goal is to study glass fiber and washed ramie fiber composites focusing on the effect of varying both the fiber length (25, 35, 45 and 55 mm) and the fiber composition. The overall fiber loading was maintained constant (21 vol.%). Based on the results obtained, the washed ramie fiber may be considered as an alternative for the production of these composites. The higher flexural strength presented being observed for 45 mm fiber length composite, although this difference is not significant for lower glass fiber volume fractions: (0:100) and (25:75). Also, by increasing the relative volume fraction of glass fiber until an upper limit of 75%, higher flexural and impact properties were obtained.

Post-consumer polyethylene terephthalate and polyamide 66 blends and corresponding short glass fiber reinforced composites

Novello,Marcus Vinicius; Carreira,Lilian Gasparelli; Canto,Leonardo Bresciani
Fonte: ABM, ABC, ABPol Publicador: ABM, ABC, ABPol
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2014 EN
Relevância na Pesquisa
66.34%
Blends of bottle-grade post-consumer polyethylene terephthalate (PET) and virgin polyamide 66 (PA66), over the complete composition range, and corresponding short glass fiber (SGF) reinforced composites were investigated. These materials were compounded in a twin-screw extruder and injection molded as standard specimens. Morphological investigation of the composites revealed that the short glass fibers have a good size distribution and are homogenously dispersed within a polymeric matrix. The PET/PA66/SGF composites showed good mechanical performance in flexural, tensile and impact tests demonstrating that the addition of SGFs to PET/PA66 blends is an interesting approach to obtaining new thermoplastic composites. In addition, this represents a potential application for post-consumer PET, an abundant and cheap material, in the well-established market of PA66/SGF composites, which are widely used in technical parts requiring high mechanical and thermal properties.

Fracture characteristics and anisotropy in notched glass fiber reinforced plastics

Tinô,Sérgio Renan Lopes; Aquino,Eve Maria Freire de
Fonte: ABM, ABC, ABPol Publicador: ABM, ABC, ABPol
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2014 EN
Relevância na Pesquisa
66.29%
The damage mechanism of reinforced plastics may be present in many different ways, since it depends on many factors. Highlights may be given to the effect of stress concentration in of geometric discontinuity in the sections of these structural elements, which in general always leads to certain characteristics of the fracture. In the case of glass fiber reinforced plastics (GFRP) it is expected the same tendency, beyond the influence of reinforcement and its internal orientation in the layers (anisotropy). The aims of this work are detailed study of the influence of the holes (longituninal section) in the characteristic fracture in GFRP submitted to tensile loading. Three different configurations of composite laminates were studied: two reinforced with Eglassfiber bidirectional textil fabric and the other only with short mats, also Eglassfiber. The results showed the influence of all parameters listed above in the final fracture characteristics and residual properties.

Glass fiber resin composites and components at arctic temperatures

Miller, Douglas O.
Fonte: Monterey, California: Naval Postgraduate School Publicador: Monterey, California: Naval Postgraduate School
Tipo: Tese de Doutorado
Relevância na Pesquisa
66.42%
Approved for public release; distribution is unlimited; Glass fiber reinforced composites (GFRC) are used in a wide variety of applications within the U.S. Navy. With a potential increase in arctic operations in the Navy’s future, it is important to understand how GFRCs will react at arctic temperatures. Previous research has shown that material properties of GFRC at cold temperatures are dependent on the reaction between the fiber and the resin, but little research has been conducted that was geared toward naval applications at arctic temperatures. This thesis focuses on the tensile properties of GFRC, resin, and glass fiber used in previous NPS-related composite research. The properties of the individual components are compared to assist in the design of composite structures, and provide a baseline to assess the need to re-conduct previous composite experiments at arctic temperatures.; ; Lieutenant, United States Navy

Influence of ferrule preparation with or without glass fiber post on fracture resistance of endodontically treated teeth

LIMA, Alexandra Furtado de; SPAZZIN, Aloísio Oro; GALAFASSI, Daniel; CORRER-SOBRINHO, Lourenço; CARLINI-JÚNIOR, Bruno
Fonte: Faculdade De Odontologia De Bauru - USP Publicador: Faculdade De Odontologia De Bauru - USP
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
66.39%
OBJECTIVE: This study evaluated the effect of ferrule preparation (Fp) on the fracture resistance of endodontically treated teeth, restored with composite resin cores with or without glass fiber posts. MATERIAL AND METHODS: Forty-four bovine teeth were sectioned 19 or 17 mm (2 mm ferrule) from the apex, endodontically treated and assigned to four groups (n = 11): Group 1: Fp and post; Group 2: Fp and without post; Group 3: without Fp and with post; Group 4: without Fp and without post. All specimens were restored with composite resin core and metal crown. Specimens were subjected to fracture resistance testing in a universal testing machine at a crosshead speed of 0.5 mm/min. The data were analyzed by two-way ANOVA and Tukey's tests (α=0.05). RESULTS: The mean fracture resistance values were as follows: Group 1: 573.3 N; Group 2: 552.5 N; Group 3: 275.3 N; Group 4: 258.6 N. Significantly higher fracture resistance was found for the groups with Fp (p<0.001). CONCLUSION: There was no statistically significant interaction between the "Fp" and "post" factors (p = 0.954). The ferrule preparation increased the fracture resistance of endodontically treated teeth. However, the use of glass fiber post showed no significant influence on the fracture resistance.

In vitro fracture resistance of glass-fiber and cast metal posts with different designs; Resistência à fratura de pinos de fibra de vidro e metálicos fundidos com diferentes configurações

Pasqualin, Fábio Henrique; Giovani, Alessandro Rogério; Sousa Neto, Manoel Damião de; Paulino, Silvana Maria; Vansan, Luiz Pascoal
Fonte: Pontifícia Universidade Católica do Rio Grande do Sul Publicador: Pontifícia Universidade Católica do Rio Grande do Sul
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
56.6%
PURPOSE: To evaluate the in vitro fracture resistance of roots with glass-fiber and metal dowels with different designs. METHODS: Fifty-endodontically treated maxillary central incisors were embedded in acrylic resin. Ten of them received only the coronary preparation, and the remaining forty were embedded (except for 4mm of the cervical area) after removing the clinical crowns. Specimens were divided into five groups (n=10): control (teeth with only coronary preparation), cylindrical cast dowel, conical cast dowel, cylindrical glass-fiber dowel and conical glass-fiber dowel. Specimens were subjected to an increasing compressive load (N) until fracture. RESULTS: ANOVA indicated significant difference (P<.05) among the groups, and the Tukey-Kramer´s test identified these differences. The control group (867±243 N) presented the highest values and was statistically similar to cylindrical glass-fiber dowel group (711±180 N). There is no significant difference among the metal dowel cylindrical (435±245 N) or conical (585±164 N) group and conical glass-fiber dowel (453±112 N). Cylindrical glass-fiber dowel (711±180 N) and conical cast dowel and core (585±164 N) groups had intermediate values and did not differ from each other. CONCLUSIONS: Cylindrical glass fiber dowels represent a viable alternative to the cast-metal dowel cylindrical or conical. Cylindrical glass fiber dowels also increase endodontically treated incisors' resistance to fracture.

Aplicação de polipropileno com 35% de fibra de vidro (PP GF35) em substituição à poliamida com 35% de fibra de vidro (PA6 GF35) na fabricação de coletores de admissão em motores de 03 cilindros Bi-combustível; Application of polypropylene with 35% of glass fiber (PP GF35) in order to substitute the polyamide with 35% of glass fiber (PA6 GF35) in the intake manifold in downsizing engine flex fuel of three cylinders

Paulo César Corredori
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 31/07/2015 PT
Relevância na Pesquisa
66.46%
Este mundo que vivemos está se tornando extremamente competitivo dia após dia, a apenas cinquenta anos, os motores ciclo Otto permaneciam quase os mesmos quando foram inventados pelo engenheiro alemão Nikolaus August Otto no final do século 19. Foi somente no final da década de 1970 que os antigos motores começaram a ganhar apelos tecnológicos, como injeção eletrônica, ignição eletrônica, controle de emissões e gás carbônico, etc., com isso, todas as montadoras começaram a buscar soluções que fizessem do seu veículo, o melhor ou o mais econômico e menos poluente. Face às novas exigências governamentais ao redor do mundo, todas as montadoras e autopeças estão trabalhando incansavelmente na busca de várias soluções, soluções estas que vão desde a diminuição de emissões evaporativas, redução do consumo de combustível, seja em função de um motor mais econômico quanto a melhorias de aerodinâmica, que resulta em menor fenômeno de arraste e consequente economia de combustível. Sabe-se também que redução de peso impacta diretamente na redução do fenômeno de arraste, portanto, gera um menor consumo de combustível, por isso, estamos vendo o crescente interesse das indústrias automotivas em substituir as antigas e atuais peças em metal que são normalmente pesadas...

Optimization method for sequential determination of Cu and Fe in airborne particulate matter collected on glass fiber filters by slurry sampling FAAS

Almeida,Tarcísio S. de; Sant'Ana,Mirna O.; Cruz,Jersica M.; Tormen,Luciano; Curtiu,Adilson J.; Alves,José do Patrocínio H.; Garcia,Carlos A. B.; Santos,Pericles A.; Araujo,Rennan G. O.
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2013 EN
Relevância na Pesquisa
66.29%
A slurry sampling flame atomic absorption spectrometric method for sequential determination of Cu and Fe in airborne particulate matter (APM) collected on glass fiber filters is proposed. The method optimization was carried out using a dry powdered sample (filter + APM) mass of 50 mg, dispersed in 0.5 mol L-1 nitric acid solution and under ultrasonic bath for 10 min. The limits of detection (n = 10) were 4 and 14 µg g-1 for Cu and Fe on the filter, respectively. The repeatability expressed as the relative standard deviation was better than 7 and 8% (n = 3) for Cu and Fe, respectively. The accuracy of the method was confirmed by analysis of the fly ash certified reference material (BCR 176R). The results obtained for six samples of APM using the proposed method showed no significant differences with those obtained after microwave-assisted acid extraction and determination by inductively coupled plasma mass spectrometry. The analytical method proved to be simple, fast and reliable.

In vitro fracture resistance of glass-fiber and cast metal posts with different designs

Pasqualin,Fábio Henrique; Giovani,Alessandro Rogério; Sousa Neto,Manoel Damião de; Paulino,Silvana Maria; Vansan,Luiz Pascoal
Fonte: Pontifícia Universidade Católica do Rio Grande do Sul Publicador: Pontifícia Universidade Católica do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 EN
Relevância na Pesquisa
56.6%
PURPOSE: To evaluate the in vitro fracture resistance of roots with glass-fiber and metal dowels with different designs. METHODS: Fifty-endodontically treated maxillary central incisors were embedded in acrylic resin. Ten of them received only the coronary preparation, and the remaining forty were embedded (except for 4mm of the cervical area) after removing the clinical crowns. Specimens were divided into five groups (n=10): control (teeth with only coronary preparation), cylindrical cast dowel, conical cast dowel, cylindrical glass-fiber dowel and conical glass-fiber dowel. Specimens were subjected to an increasing compressive load (N) until fracture. RESULTS: ANOVA indicated significant difference (P<.05) among the groups, and the Tukey-Kramer´s test identified these differences. The control group (867±243 N) presented the highest values and was statistically similar to cylindrical glass-fiber dowel group (711±180 N). There is no significant difference among the metal dowel cylindrical (435±245 N) or conical (585±164 N) group and conical glass-fiber dowel (453±112 N). Cylindrical glass-fiber dowel (711±180 N) and conical cast dowel and core (585±164 N) groups had intermediate values and did not differ from each other. CONCLUSIONS: Cylindrical glass fiber dowels represent a viable alternative to the cast-metal dowel cylindrical or conical. Cylindrical glass fiber dowels also increase endodontically treated incisors' resistance to fracture.

Influence of ferrule preparation with or without glass fiber post on fracture resistance of endodontically treated teeth

Lima,Alexandra Furtado de; Spazzin,Aloísio Oro; Galafassi,Daniel; Correr-Sobrinho,Lourenço; Carlini-Júnior,Bruno
Fonte: Faculdade De Odontologia De Bauru - USP Publicador: Faculdade De Odontologia De Bauru - USP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2010 EN
Relevância na Pesquisa
66.39%
OBJECTIVE: This study evaluated the effect of ferrule preparation (Fp) on the fracture resistance of endodontically treated teeth, restored with composite resin cores with or without glass fiber posts. MATERIAL AND METHODS: Forty-four bovine teeth were sectioned 19 or 17 mm (2 mm ferrule) from the apex, endodontically treated and assigned to four groups (n = 11): Group 1: Fp and post; Group 2: Fp and without post; Group 3: without Fp and with post; Group 4: without Fp and without post. All specimens were restored with composite resin core and metal crown. Specimens were subjected to fracture resistance testing in a universal testing machine at a crosshead speed of 0.5 mm/min. The data were analyzed by two-way ANOVA and Tukey's tests (α=0.05). RESULTS: The mean fracture resistance values were as follows: Group 1: 573.3 N; Group 2: 552.5 N; Group 3: 275.3 N; Group 4: 258.6 N. Significantly higher fracture resistance was found for the groups with Fp (p<0.001). CONCLUSION: There was no statistically significant interaction between the "Fp" and "post" factors (p = 0.954). The ferrule preparation increased the fracture resistance of endodontically treated teeth. However, the use of glass fiber post showed no significant influence on the fracture resistance.

Tensile Strength of Glass Fiber Posts Submitted to Different Surface Treatments

Faria,Maria Isabel A.; Gomes,Erica Alves; Messias,Danielle Cristine; Silva Filho,Joao Manoel; Souza Filho,Celso Bernardo; Paulino,Silvana Maria
Fonte: Fundação Odontológica de Ribeirão Preto Publicador: Fundação Odontológica de Ribeirão Preto
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2013 EN
Relevância na Pesquisa
66.29%
The aim of this in vitro study was to evaluate the tensile strength of glass fiber posts submitted to different surface treatments. Forty-eight maxillary canines had their crowns sectioned and root canals endodontically treated. The roots were embedded in acrylic resin and distributed into 3 groups according to the surface treatment: Group I: the posts were treated with silane agent for 30 s and adhesive; Group II: the posts were cleaned with alcohol before treatment with silane agent and adhesive; Group III: the posts were submitted to conditioning with 37% phosphoric acid for 30 s before treatment with silane agent and adhesive. Each group was divided into 2 subgroups for adhesive polymerization or not before insertion into the canal: A - adhesive was not light cured and B - adhesive was light cured. All posts were cemented with Panavia F and the samples were subjected to tensile strength test in a universal testing machine at crosshead speed of 1 mm/min. Data were submitted to one-way ANOVA and Tukey's test at 5% significance level. There was statistically significant difference (p<0.01) only between group GIII-B and groups GI-A and GI-B. No significant difference was found among the other groups (p>0.05). It was concluded that the products used for cleaning the posts influenced the retention regardless of adhesive light curing.

Influence of ferrule preparation with or without glass fiber post on fracture resistance of endodontically treated teeth

Lima, Alexandra Furtado de; Spazzin, Aloísio Oro; Galafassi, Daniel; Correr-Sobrinho, Lourenço; Carlini-Júnior, Bruno
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 01/08/2010 ENG
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OBJECTIVE: This study evaluated the effect of ferrule preparation (Fp) on the fracture resistance of endodontically treated teeth, restored with composite resin cores with or without glass fiber posts. MATERIAL AND METHODS: Forty-four bovine teeth were sectioned 19 or 17 mm (2 mm ferrule) from the apex, endodontically treated and assigned to four groups (n = 11): Group 1: Fp and post; Group 2: Fp and without post; Group 3: without Fp and with post; Group 4: without Fp and without post. All specimens were restored with composite resin core and metal crown. Specimens were subjected to fracture resistance testing in a universal testing machine at a crosshead speed of 0.5 mm/min. The data were analyzed by two-way ANOVA and Tukey's tests (α=0.05). RESULTS: The mean fracture resistance values were as follows: Group 1: 573.3 N; Group 2: 552.5 N; Group 3: 275.3 N; Group 4: 258.6 N. Significantly higher fracture resistance was found for the groups with Fp (p