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Santos, Rodrigo Falci - One of the best experts on this subject based on the ideXlab platform.

  • Avaliação microtomográfica de enxertos ósseos fixados pelo etil - cianoacrilato: um estudo experimental em ratos
    Universidade Federal de Juiz de Fora, 2013
    Co-Authors: Santos, Rodrigo Falci
    Abstract:

    Este ensaio pré-clínico se propôs avaliar e comparar o volume ósseo na interface enxerto/leito receptor, utilizando o etil-cianoacrilato (Super Bonder Flex Gel®) e parafusos de titânio como agentes de fixação na incorporação de enxertos ósseos, verificado por meio de microtomografia computadorizada. Para tal, utilizou-se 12 ratos, da espécie Rattus novergicos albinus, (Wistar), machos adultos com aproximadamente três meses de idade. Os animais foram aleatoriamente divididos em dois grupos de seis, com um grupo controle (grupo Parafuso Titânio – PT), no qual foi utilizado um parafuso de fixação interna rígida para estabilização do enxerto, e um grupo experimental (grupo Super Bonder Flex Gel® - SB) , no qual foi aplicado o adesivo para estabilizar o enxerto ósseo. O procedimento foi realizado sob anestesia geral, removendo-se um enxerto em bloco do osso parietal esquerdo e fixando-o no osso parietal direito na calvária dos animais. Após 30 dias de cirurgia os 12 animais foram submetidos à eutanásia e o material enxertado foi submetido à análise microtomográfica. O teste U de Mann Whitney, não mostrou diferença estatisticamente significativa entre os parâmetros avaliados (volume total-TV, volume ósseo-BV, fração do volume-BV/TV, espessura trabecular-Tb.Th, distância intertrabecular-TB.Sp e número de trabéculas-Tb.N) em ambos os grupos, com exceção da distância entre as trabéculas (Tb.Sp). O grupo SB apresentou uma Tb.Sb significativamente maior (p=0,015). Desta forma pode-se concluir que o exame de microtomografia computadorizada foi capaz de detectar formações de tecido ósseo mineralizado na interface enxerto/leito receptor após 30 dias do experimento. Além disso, o etil-cianoacrilato foi tão eficiente quanto o parafuso de titânio na estabilização e incorporação do enxerto ósseo na calvária de ratos, tanto em relação aos parâmetros volumétricos, quanto em relação aos parâmetros de densidade óssea.This preclinical trial was developed with the aim of evaluating and comparing the bone volume in the interface bone / graft, using Ethyl-Cyanoacrylate (Super Bonder Flex Gel ®) and titanium screws as fixing agents in bone graft incorporation, evaluated by computed microtomography. To verify the efficiency of the tested product, 12 adult male rats of the species Rattus novergicos albinus (Wistar) of approximately three months of age were randomly divided into two groups of six rats each. In the control group (PT), a screw internal fixation was used to stabilize the graft. In the experimental group (SB) an adhesive of Ethyl- Cyanoacrylate was used. Under general anesthesial a block graft was removed from the left parietal bone and fixed on the right parietal bone, in the calvaria of the animal. Thirty days after the surgery, all animals were euthanized and the grafted material analyzed by computed microtomography. The Mann Whitney U test did not show any statistically significant difference between the proposed parameters (Total volume – TV, Bone volume – BV, Bone volume fraction – BV/TV, Trabecular thickness – Tb.Th, Trabecular separation – Tb.Sp and Trabecular number – Tb.N) in both groups, except for the Trabecular separation (Tb.Sp). The SB group presented a Tb.Sb higher than the PT group (p = 0.015) with statistical significance. Therefore, was possible to conclude that the computed microtomography test was able to detect mineralized bone tissue formations in the interface bone / graft after 30 days. Also the volumetric parameters and the parameters of bone density for Ethyl-Cyanoacrylate was as efficient as the titanium screw in bone graft incorporation in rat calvaria

  • Avaliação microtomográfica de enxertos ósseos fixados pelo etil - cianoacrilato: um estudo experimental em ratos
    'Revista Educacao em Foco (UFJF)', 2013
    Co-Authors: Santos, Rodrigo Falci
    Abstract:

    This preclinical trial was developed with the aim of evaluating and comparing the bone volume in the interface bone / graft, using Ethyl-Cyanoacrylate (Super Bonder Flex Gel ®) and titanium screws as fixing agents in bone graft incorporation, evaluated by computed microtomography. To verify the efficiency of the tested product, 12 adult male rats of the species Rattus novergicos albinus (Wistar) of approximately three months of age were randomly divided into two groups of six rats each. In the control group (PT), a screw internal fixation was used to stabilize the graft. In the experimental group (SB) an adhesive of Ethyl- Cyanoacrylate was used. Under general anesthesial a block graft was removed from the left parietal bone and fixed on the right parietal bone, in the calvaria of the animal. Thirty days after the surgery, all animals were euthanized and the grafted material analyzed by computed microtomography. The Mann Whitney U test did not show any statistically significant difference between the proposed parameters (Total volume – TV, Bone volume – BV, Bone volume fraction – BV/TV, Trabecular thickness – Tb.Th, Trabecular separation – Tb.Sp and Trabecular number – Tb.N) in both groups, except for the Trabecular separation (Tb.Sp). The SB group presented a Tb.Sb higher than the PT group (p = 0.015) with statistical significance. Therefore, was possible to conclude that the computed microtomography test was able to detect mineralized bone tissue formations in the interface bone / graft after 30 days. Also the volumetric parameters and the parameters of bone density for Ethyl-Cyanoacrylate was as efficient as the titanium screw in bone graft incorporation in rat calvaria.Este ensaio pré-clínico se propôs avaliar e comparar o volume ósseo na interface enxerto/leito receptor, utilizando o etil-cianoacrilato (Super Bonder Flex Gel®) e parafusos de titânio como agentes de fixação na incorporação de enxertos ósseos, verificado por meio de microtomografia computadorizada. Para tal, utilizou-se 12 ratos, da espécie Rattus novergicos albinus, (Wistar), machos adultos com aproximadamente três meses de idade. Os animais foram aleatoriamente divididos em dois grupos de seis, com um grupo controle (grupo Parafuso Titânio – PT), no qual foi utilizado um parafuso de fixação interna rígida para estabilização do enxerto, e um grupo experimental (grupo Super Bonder Flex Gel® - SB) , no qual foi aplicado o adesivo para estabilizar o enxerto ósseo. O procedimento foi realizado sob anestesia geral, removendo-se um enxerto em bloco do osso parietal esquerdo e fixando-o no osso parietal direito na calvária dos animais. Após 30 dias de cirurgia os 12 animais foram submetidos à eutanásia e o material enxertado foi submetido à análise microtomográfica. O teste U de Mann Whitney, não mostrou diferença estatisticamente significativa entre os parâmetros avaliados (volume total-TV, volume ósseo-BV, fração do volume-BV/TV, espessura trabecular-Tb.Th, distância intertrabecular-TB.Sp e número de trabéculas-Tb.N) em ambos os grupos, com exceção da distância entre as trabéculas (Tb.Sp). O grupo SB apresentou uma Tb.Sb significativamente maior (p=0,015). Desta forma pode-se concluir que o exame de microtomografia computadorizada foi capaz de detectar formações de tecido ósseo mineralizado na interface enxerto/leito receptor após 30 dias do experimento. Além disso, o etil-cianoacrilato foi tão eficiente quanto o parafuso de titânio na estabilização e incorporação do enxerto ósseo na calvária de ratos, tanto em relação aos parâmetros volumétricos, quanto em relação aos parâmetros de densidade óssea.FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerai

K E Evans - One of the best experts on this subject based on the ideXlab platform.

  • investigation of the dual setting mechanism of a novel dental cement using infrared spectroscopy
    Vibrational Spectroscopy, 2007
    Co-Authors: Susannah K Tomlinson, Oana Ghita, R M Hooper, K E Evans
    Abstract:

    Abstract Mid-IR spectroscopy has been used to analyse the setting of a novel, ‘hybrid’ cement (ECGIC), which incorporates an Ethyl Cyanoacrylate into a dental glass-ionomer cement (GIC) formulation. For comparison, a conventional, commercially available GIC (Diamond Carve) and the unfilled Ethyl Cyanoacrylate have also been investigated. The sequence of the setting reactions in dental cements is important as these will affect the handling characteristics and the overall mechanical properties of the cements. In the spectra of ECGIC, both the acid–base reaction (of the GIC component) and the Cyanoacrylate polymerisation have been identified and discussed. The spectra indicate that the Cyanoacrylate polymerisation is complete after approximately 6–7 min, while the acid–base reaction is still continuing 45 min after mixing.

  • monomer conversion and hardness of novel dental cements based on Ethyl Cyanoacrylate
    Dental Materials, 2007
    Co-Authors: Susannah K Tomlinson, Oana Ghita, R M Hooper, K E Evans
    Abstract:

    OBJECTIVES: The aim of this work was to study the setting of two novel dental cements: (i) a 'hybrid' cement, incorporating an Ethyl Cyanoacrylate into a glass-ionomer cement (ECGIC) formulation and (ii) an Ethyl Cyanoacrylate/hydroxyapatite composite cement (ECHC). The mechanical role of the Cyanoacrylate and its curing within the cements have been discussed. METHODS: The setting of the cements was characterised using Vickers indentation hardness and near-infrared (near-IR) spectroscopy. RESULTS: The Cyanoacrylate component of ECGIC was 100% cured approximately 10min after the initial cement mixing. The ECGIC continued to increase in hardness after the Cyanoacrylate component was fully cured. This proved that the fully polymerised network of Cyanoacrylate did not prevent the acid-base reactions of the GIC components from continuing. The Vickers hardness number of ECGIC at 18 weeks was approximately 105. The curing of the Cyanoacrylate within ECHC was much slower and was still not complete (98%) 18 weeks after the initial cement mixing. The hardness of the ECHC was shown to be correlated with the extent of Cyanoacrylate cure. The Vickers hardness number of ECHC at 18 weeks was approximately 21. The primary reasons for the overall lower hardness of ECHC in comparison to ECGIC were the lower powder:liquid ratio and the softer filler type. SIGNIFICANCE: Careful consideration is needed when incorporating Cyanoacrylates into dental cements, as speed of cure and hardness are particularly important.

  • the use of near infrared spectroscopy for the cure monitoring of an Ethyl Cyanoacrylate adhesive
    Vibrational Spectroscopy, 2006
    Co-Authors: Susannah K Tomlinson, Oana Ghita, R M Hooper, K E Evans
    Abstract:

    Near-IR reflectance spectroscopy has been used to study the curing of Ethyl Cyanoacrylate adhesive on polished dental glass and microscope slide substrates. The effects of changing the glue film thickness and the type of substrate on the curing rate have been investigated whilst maintaining a constant humidity. The FTIR spectral data has been used to calculate and plot the extents of cure versus time for various film thicknesses.

Neal Murphy - One of the best experts on this subject based on the ideXlab platform.

  • dynamic mechanical analysis of carbon black filled elastomer toughened Ethyl Cyanoacrylate adhesive bulk films
    International Journal of Adhesion and Adhesives, 2020
    Co-Authors: Tatiana Stefanov, Bernard Ryan, Alojz Ivankovic, Neal Murphy
    Abstract:

    Abstract This paper reports on a dynamic mechanical analysis (DMA) study of carbon black filled, elastomer-toughened Ethyl Cyanoacrylate (ETECA) adhesive bulk films. The bulk films were cured at room temperature, both with and without premixed initiators, between poly (Ethylene) (PE) substrates and in poly (tetrafluoroEthylene) (PTFE) moulds. Adhesive batches with different strong and weak acid concentrations were used to study the influence of the curing speed on the phase separation behaviour of the elastomer. The mechanical properties of the bulk adhesive films and electron micrographs of the fracture surface of the tensile tested bulk specimens are reported in the previous publication by Ștefanov et al. [1; International Journal of Adhesion & Adhesives, 68: 142–155, 2016]. For all tested bulk adhesive films similar peaks were observed in the DMA curves, i.e., a peak at low temperature, before the glass transition region of the polymer, and a peak corresponding to the glass transition temperature of the poly (Cyanoacrylate) adhesive. The results of this investigation show that the amount of the phase-separated elastomer increases with the increase in weak acid concentration for the samples cured without the use of initiators. An opposite trend was observed for the samples cured using initiators. Another important finding is that for a complete phase-separation of the elastomer from the poly CA a secondary step, following curing at room temperature, is necessary which should consist of heating the sample to 110 °C.

  • mechanical bulk properties and fracture toughness of composite to composite joints of an elastomer toughened Ethyl Cyanoacrylate adhesive
    International Journal of Adhesion and Adhesives, 2016
    Co-Authors: Tatiana Stefanov, Bernard Ryan, Alojz Ivankovic, Neal Murphy
    Abstract:

    Abstract The bulk mechanical and fracture characterisation of an elastomer-toughened Ethyl Cyanoacrylate adhesive were investigated using thin film and standard double cantilever beam specimens, respectively. It is shown that these properties are strongly dependent on the prevailing curing conditions. These in turn are influenced by factors such as surface chemistry, curing time, the use of initiators, and the concentration of stabilizing acids in the system which have a profound effect on the polymerisation reaction. The curing conditions in turn have been shown to greatly influence the phase separation of the elastomeric toughening agent and the effectiveness of its associated toughening mechanism.

Barbosa, Virginia Tessarine - One of the best experts on this subject based on the ideXlab platform.

  • Emprego do etil-cianoacrilato ou do octil-cianoacrilato no preenchimento de lesões corneais, após ceratectomia lamelar em coelhos
    Universidade Estadual Paulista (UNESP), 2007
    Co-Authors: Barbosa, Virginia Tessarine
    Abstract:

    São diversas as indicações para o emprego de adesivos derivados do cianoacrilato na área médica. Em oftalmologia humana, há décadas, estes biomateriais são utilizados com resultados satisfatórios. Entretanto, em veterinária, ainda são escassos o conhecimento de suas propriedades e a sua aplicação. Considerando o interesse em se avaliar o comportamento do etil-cianoacrilato, comparativamente ao octil-cianoacrilato, clínica e histopatologicamente, em córneas de coelhos, empregaramse 36 animais, nos quais, após ceratectomia lemelar de 3 mm de diâmetro, os adesivos foram aplicados e recobertos por uma fina película acelular. No pós-operatório, foram realizadas avaliações gerais (dias 1 a 10), exames oftálmicos (dias 0, 1, 3, 5, 7, 10, 14, 21, 30, 44 e 60) e estudos histopatológicos (períodos 3, 7, 14, 21, 30 e 60). Consideraram-se, ainda, os custos e disponibilidade dos adesivos. Clinicamente, houve diferença significativa para as variáveis, consumo de água, atitude, blefarite, edema corneal, teste da fluoresceína e tempo de permanência dos adesivos. À histopatologia, para o etil-cianoacrilato, já nos primeiros períodos de avaliação, observou-se epitelização corneal, organização do colágeno e moderada reação inflamatória. Para o octil-cianoacrilato, constatou-se a permanência do adesivo até as fases mais tardias, sob o qual, mais lentamente os eventos de reepitelização e organização do colágeno ocorreram com reação inflamatória discreta. Os custos e disponibilidade de aquisição do etil-cianoacrilato foram mais acessíveis do que os do octil-cianoacrilato.There are several indications for the employment of adhesives derived from the Cyanoacrylate in the medical area. In human ophthalmology, from decades, the Cyanoacrylates have been used with satisfactory results. However, in veterinary medicine, there is a scarcity of knowledge of its properties and applications. Considering the objective of evaluating the behavior of the Ethyl-Cyanoacrylate, comparatively to octhyl-Cyanoacrylate, clinically and histopatologically, in rabbit corneas, there were used 36 animals. After lamellar keratectomy with 3 mm of diameter the adhesives was applied and recovered with a fine pellicle. In the post operative period general (days 1 to 10), ophthalmic (days 0, 1, 3, 5, 7, 14, 21, 30, 44 and 60) and hystopathologic (periods 3, 7, 14, 21, 30 and 60) exams was performed. There was also considered the costs and accessibility of the adhesives. Clinically, there were significant differences for the variables water consumption, attitude, blepharitis, corneal edema, fluorescein test and adhesive permanence time. With respect to the histopathological evaluation, for the treatment with Ethyl-Cyanoacrylate, there was observed already in the very first periods of evaluation, corneal epitelization, collagen organization and moderate inflammatory reaction. For the octhyl-Cyanoacrylate treatment, there was observed the adhesive permanence until later phases, under which more vagarously the events of reepithelization and collagen organization occurred with a discrete inflammatory reaction. The Ethyl-Cyanoacrylate presented minor costs and more facility to acquire.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Barbosa, Virginia Tessarine [unesp] - One of the best experts on this subject based on the ideXlab platform.

  • Emprego do etil-cianoacrilato ou do octil-cianoacrilato no preenchimento de lesões corneais, após ceratectomia lamelar em coelhos
    Universidade Estadual Paulista (UNESP), 2007
    Co-Authors: Barbosa, Virginia Tessarine [unesp]
    Abstract:

    São diversas as indicações para o emprego de adesivos derivados do cianoacrilato na área médica. Em oftalmologia humana, há décadas, estes biomateriais são utilizados com resultados satisfatórios. Entretanto, em veterinária, ainda são escassos o conhecimento de suas propriedades e a sua aplicação. Considerando o interesse em se avaliar o comportamento do etil-cianoacrilato, comparativamente ao octil-cianoacrilato, clínica e histopatologicamente, em córneas de coelhos, empregaramse 36 animais, nos quais, após ceratectomia lemelar de 3 mm de diâmetro, os adesivos foram aplicados e recobertos por uma fina película acelular. No pós-operatório, foram realizadas avaliações gerais (dias 1 a 10), exames oftálmicos (dias 0, 1, 3, 5, 7, 10, 14, 21, 30, 44 e 60) e estudos histopatológicos (períodos 3, 7, 14, 21, 30 e 60). Consideraram-se, ainda, os custos e disponibilidade dos adesivos. Clinicamente, houve diferença significativa para as variáveis, consumo de água, atitude, blefarite, edema corneal, teste da fluoresceína e tempo de permanência dos adesivos. À histopatologia, para o etil-cianoacrilato, já nos primeiros períodos de avaliação, observou-se epitelização corneal, organização do colágeno e moderada reação inflamatória. Para o octil-cianoacrilato, constatou-se a permanência do adesivo até as fases mais tardias, sob o qual, mais lentamente os eventos de reepitelização e organização do colágeno ocorreram com reação inflamatória discreta. Os custos e disponibilidade de aquisição do etil-cianoacrilato foram mais acessíveis do que os do octil-cianoacrilato.There are several indications for the employment of adhesives derived from the Cyanoacrylate in the medical area. In human ophthalmology, from decades, the Cyanoacrylates have been used with satisfactory results. However, in veterinary medicine, there is a scarcity of knowledge of its properties and applications. Considering the objective of evaluating the behavior of the Ethyl-Cyanoacrylate, comparatively to octhyl-Cyanoacrylate, clinically and histopatologically, in rabbit corneas, there were used 36 animals. After lamellar keratectomy with 3 mm of diameter the adhesives was applied and recovered with a fine pellicle. In the post operative period general (days 1 to 10), ophthalmic (days 0, 1, 3, 5, 7, 14, 21, 30, 44 and 60) and hystopathologic (periods 3, 7, 14, 21, 30 and 60) exams was performed. There was also considered the costs and accessibility of the adhesives. Clinically, there were significant differences for the variables water consumption, attitude, blepharitis, corneal edema, fluorescein test and adhesive permanence time. With respect to the histopathological evaluation, for the treatment with Ethyl-Cyanoacrylate, there was observed already in the very first periods of evaluation, corneal epitelization, collagen organization and moderate inflammatory reaction. For the octhyl-Cyanoacrylate treatment, there was observed the adhesive permanence until later phases, under which more vagarously the events of reepithelization and collagen organization occurred with a discrete inflammatory reaction. The Ethyl-Cyanoacrylate presented minor costs and more facility to acquire