Base de dados : LILACS
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Referências encontradas : 14 [refinar]
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Id: biblio-889495
Autor: Gonçalves, Flávia; Campos, Luiza Mello de Paiva; Rodrigues-Júnior, Ezequias Costa; Costa, Fabrícia Viana; Marques, Pamela Adeline; Francci, Carlos Eduardo; Braga, Roberto Ruggiero; Boaro, Letícia Cristina Cidreira.
Título: A comparative study of bulk-fill composites: degree of conversion, post-gel shrinkage and cytotoxicity
Fonte: Braz. oral res. (Online);32:e17, 2018. tab, graf.
Idioma: en.
Projeto: FAPESP.
Resumo: Abstract: Bulk-fill composites are claimed to be restorative materials used in deep preparations and effectively photoactivated in layers up to 4 mm. The aim of the present study was to evaluate the degree of conversion, post-gel volumetric shrinkage, and cytotoxicity of six bulk-fill and two conventional composites. Degree of conversion was determined by FTIR spectroscopy; post-gel volumetric shrinkage was determined using the strain gauge method; and cytotoxicity in human fibroblasts was evaluated indirectly by the MTT assay. Data were subjected to one-way ANOVA/Tukey's test (α = 0.05). All materials, including bulk-fill and conventional composites, were classified as non-toxic, with cell viability higher than 70%. Bulk-fill composites exhibited volumetric shrinkage similar to or lower (1.4 to 0.4%) than that of conventional composites (1.7-2.1%). However, only four of the bulk-fill composites were able to sustain a homogeneous conversion at the 4-mm depth. Despite their non-toxicity and shrinkage similar to that of conventional materials, not all commercial bulk-fill materials were able to maintain a conversion as high as 80% of the superficial layer, at the 4-mm depth, indicating some failure in the bulk-fill design of some commercial brands. Therefore, the use of bulk-fill materials in dental practice is advantageous, but special attention should be given to the selection and correct use of the materials.
Descritores: Resinas Compostas/toxicidade
Resinas Compostas/química
Polimerização
-Valores de Referência
Propriedades de Superfície
Fatores de Tempo
Teste de Materiais
Sobrevivência Celular/efeitos dos fármacos
Reprodutibilidade dos Testes
Análise de Variância
Espectroscopia de Infravermelho com Transformada de Fourier
Transição de Fase
Processos Fotoquímicos
Fibroblastos/efeitos dos fármacos
Limites: Humanos
Tipo de Publ: Estudo Comparativo
Responsável: BR1.1 - BIREME


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Id: biblio-893641
Autor: BRIANEZZI, Leticia Ferreira de Freitas; MAENOSONO, Rafael Massunari; BIM JÚNIOR, Odair; ZABEU, Giovanna Speranza; PALMA-DIBB, Regina Guenka; ISHIKIRIAMA, Sérgio Kiyoshi.
Título: Does laser diode irradiation improve the degree of conversion of simplified dentin bonding systems?
Fonte: J. appl. oral sci;25(4):381-386, July-Aug. 2017. tab, graf.
Idioma: en.
Resumo: Abstract Simplified dentin-bonding systems are clinically employed for most adhesive procedures, and they are prone to hydrolytic degradation. Objective This study aimed to investigate the effect of laser diode irradiation on the degree of conversion (DC), water sorption (WS), and water solubility (WSB) of these bonding systems in an attempt to improve their physico-mechanical resistance. Material and Methods Two bonding agents were tested: a two-step total-etch system [Adper™ Single Bond 2, 3M ESPE (SB)] and a universal system [Adper™ Single Bond Universal, 3M ESPE (SU)]. Square-shaped specimens were prepared and assigned into 4 groups (n=5): SB and SU (control groups - no laser irradiation) and SB-L and SU-L [SB and SU laser (L) - irradiated groups]. DC was assessed using Fourier transform infrared spectroscopy with attenuated total reflectance. Additional uncured resin samples (≈3.0 µL, n=5) of each adhesive were also scanned for final DC calculation. For WS/WSB tests, similar specimens (n=10) were prepared and measured by monitoring the mass changes after dehydration/water storage cycles. For both tests, adhesive fluids were dropped into standardized Teflon molds (6.0×6.0×1.0 mm), irradiated with a 970-nm laser diode, and then polymerized with an LED-curing unit (1 W/cm2). Results Laser irradiation immediately before photopolymerization increased the DC (%) of the tested adhesives: SB-L>SB>SU-L>SU. For WS/WSB (μg/mm3), only the dentin bonding system (DBS) was a significant factor (p<0.05): SB>SU. Conclusion Irradiation with a laser diode improved the degree of conversion of all tested simplified dentin bonding systems, with no impact on water sorption and solubility.
Descritores: Adesivos Dentinários/efeitos da radiação
Lasers Semicondutores
Polimerização/efeitos da radiação
-Luzes de Cura Dentária
Cimentos Dentários/química
Cimentos Dentários/efeitos da radiação
Adesivos Dentinários/química
Cura Luminosa de Adesivos Dentários/métodos
Transição de Fase/efeitos da radiação
Processos Fotoquímicos/efeitos da radiação
Valores de Referência
Reprodutibilidade dos Testes
Solubilidade/efeitos da radiação
Espectroscopia de Infravermelho com Transformada de Fourier
Estatísticas não Paramétricas
Propriedades de Superfície/efeitos da radiação
Tipo de Publ: Estudo de Avaliação
Responsável: BR1.1 - BIREME


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Id: biblio-841167
Autor: BOING, Thaynara Faelly; GOMES, Giovana Mongruel; GOMES, João Carlos; REIS, Alessandra; GOMES, Osnara Maria Mongruel.
Título: Is the bonding of self-adhesive cement sensitive to root region and curing mode?
Fonte: J. appl. oral sci;25(1):2-9, Jan.-Feb. 2017. tab, graf.
Idioma: en.
Resumo: Abstract Objectives To evaluate the influence of two curing techniques on the degree of conversion (DC) of resin cements and on bond strength (BS) of fiber posts in different regions of root dentin. Material and Methods Twenty single-rooted premolars were endodontically treated, and the post spaces were prepared. The roots were randomly divided into two groups (n=10), according to the activation mode of the resin cement RelyX™ U200 (3M ESPE Saint Paul, MN, USA): conventional (continuous activation mode) and soft-start activation mode (Ramp). The posts (WhitePost DC/FGM) were cemented according to the manufacturer’s recommendations and, after one week, the roots were cross-sectioned into six discs each of 1-mm thickness, and the cervical, medium, and apical thirds of the root canals were identified. The DC was evaluated under micro-Raman spectroscopy and the BS was evaluated by the push-out test. The data were analyzed by two-way ANOVA and Tukey’s test (α=0.05). Results Neither the activation mode nor the root regions affected the DC of the resin cement. Higher BS was achieved in the soft-start group (p=0.036); lower BS was observed in the apical third compared to the other root regions (p<0.001). Irrespective of the activation mode and root region, the mixed failure mode was the most prevalent. Conclusion The BS of fiber posts to root canals can be improved by soft-started polymerization. The DC was not affected by the curing mode.
Descritores: Cavidade Pulpar/efeitos dos fármacos
Técnica para Retentor Intrarradicular
Cimentos de Resina/química
Autocura de Resinas Dentárias/métodos
-Análise de Variância
Luzes de Cura Dentária
Falha de Restauração Dentária
Análise do Estresse Dentário
Dentina/efeitos dos fármacos
Teste de Materiais
Processos Fotoquímicos
Distribuição Aleatória
Reprodutibilidade dos Testes
Tratamento do Canal Radicular/métodos
Resistência ao Cisalhamento
Análise Espectral Raman
Estatísticas não Paramétricas
Dente não Vital
Limites: Humanos
Tipo de Publ: Estudo Comparativo
Estudo de Avaliação
Responsável: BR1.1 - BIREME


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Id: biblio-841162
Autor: NOVAIS, Veridiana Resende; RAPOSO, Luís Henrique Araújo; MIRANDA, Rafael Resende de; LOPES, Camila de Carvalho Almança; SIMAMOTO JÚNIOR, Paulo Cézar; SOARES, Carlos José.
Título: Degree of conversion and bond strength of resin-cements to feldspathic ceramic using different curing modes
Fonte: J. appl. oral sci;25(1):61-68, Jan.-Feb. 2017. tab, graf.
Idioma: en.
Resumo: Abstract Resin cements have led to great advances in dental ceramic restoration techniques because of their ability to bond to both dental structures and restorative materials. Objective The aim of this study was to assess the performance of resin cements when different curing modes are used, by evaluating the degree of conversion and bond strength to a ceramic substrate. Material and Methods Three resin cements were evaluated, two dual-cured (Variolink II and RelyX ARC) and one light-cured (Variolink Veneer). The dual-cured resin cements were tested by using the dual activation mode (base and catalyst) and light-activation mode (base paste only). For degree of conversion (DC) (n=5), a 1.0 mm thick feldspathic ceramic disc was placed over the resin cement specimens and the set was light activated with a QTH unit. After 24 h storage, the DC was measured with Fourier transform infrared spectroscopy (FTIR). For microshear bond strength testing, five feldspathic ceramic discs were submitted to surface treatment, and three cylindrical resin cement specimens were bonded to each ceramic surface according to the experimental groups. After 24 h, microshear bond testing was performed at 0.5 mm/min crosshead speed until the failure. Data were submitted to one-way ANOVA followed by Tukey test (p<0.05). Scanning electron microscopy (SEM) was used for classifying the failure modes. Results Higher DC and bond strength values were shown by the resin cements cured by using the dual activation mode. The Variolink II group presented higher DC and bond strength values when using light-activation only when compared with the Variolink Veneer group. Conclusion The base paste of dual-cured resin cements in light-activation mode can be used for bonding translucent ceramic restorations of up to or less than 1.0 mm thick.
Descritores: Silicatos de Alumínio/química
Bis-Fenol A-Glicidil Metacrilato/química
Cerâmica/química
Cura Luminosa de Adesivos Dentários/métodos
Polietilenoglicóis/química
Ácidos Polimetacrílicos/química
Compostos de Potássio/química
Cimentos de Resina/química
-Análise de Variância
Luzes de Cura Dentária
Teste de Materiais
Microscopia Eletrônica de Varredura
Processos Fotoquímicos
Polimerização
Valores de Referência
Reprodutibilidade dos Testes
Resistência ao Cisalhamento
Propriedades de Superfície
Fatores de Tempo
Tipo de Publ: Estudo de Avaliação
Responsável: BR1.1 - BIREME


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Id: lil-759366
Autor: DE SOUZA, Grace; BRAGA, Roberto Ruggiero; CESAR, Paulo Francisco; LOPES, Guilherme Carpena.
Título: Correlation between clinical performance and degree of conversion of resin cements: a literature review
Fonte: J. appl. oral sci;23(4):358-368, July-Aug. 2015. ilus.
Idioma: en.
Resumo: AbstractResin-based cements have been frequently employed in clinical practice to lute indirect restorations. However, there are numerous factors that may compromise the clinical performance of those cements. The aim of this literature review is to present and discuss some of the clinical factors that may affect the performance of current resin-based luting systems. Resin cements may have three different curing mechanisms: chemical curing, photo curing or a combination of both. Chemically cured systems are recommended to be used under opaque or thick restorations, due to the reduced access of the light. Photo-cured cements are mainly indicated for translucent veneers, due to the possibility of light transmission through the restoration. Dual-cured are more versatile systems and, theoretically, can be used in either situation, since the presence of both curing mechanisms might guarantee a high degree of conversion (DC) under every condition. However, it has been demonstrated that clinical procedures and characteristics of the materials may have many different implications in the DC of currently available resin cements, affecting their mechanical properties, bond strength to the substrate and the esthetic results of the restoration. Factors such as curing mechanism, choice of adhesive system, indirect restorative material and light-curing device may affect the degree of conversion of the cement and, therefore, have an effect on the clinical performance of resin-based cements. Specific measures are to be taken to ensure a higher DC of the luting system to be used.
Descritores: Luzes de Cura Dentária
Colagem Dentária/métodos
Cimentos de Resina/química
-Colagem Dentária/instrumentação
Dureza
Processos Fotoquímicos
Autocura de Resinas Dentárias/métodos
Fatores de Tempo
Limites: Humanos
Tipo de Publ: Revisão
Responsável: BR1.1 - BIREME


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Id: lil-699917
Autor: YOSHIDA, Keiichi; MENG, Xiangfeng.
Título: Influence of light-exposure methods and depths of cavity on the microhardness of dual-cured core build-up resin composites
Fonte: J. appl. oral sci;22(1):44-51, Jan-Feb/2014. tab, graf.
Idioma: en.
Resumo: Objective: The purpose of this study was to evaluate the Knoop hardness number (KHN) of dual-cured core build-up resin composites (DCBRCs) at 6 depths of cavity after 3 post-irradiation times by 4 light-exposure methods. Material and Methods: Five specimens each of DCBRCs (Clearfil DC Core Plus [DCP] and Unifil Core EM [UCE]) were filled in acrylic resin blocks with a semi-cylindrical cavity and light-cured using an LED light unit (power density: 1,000 mW/cm2)at the top surface by irradiation for 20 seconds (20 s), 40 seconds (40 s), bonding agent plus 20 seconds (B+20 s), or 40 seconds plus light irradiation of both sides of each acrylic resin block for 40 seconds each (120 s). KHN was measured at depths of 0.5, 2.0, 4.0, 6.0, 8.0, and 10.0 mm at 0.5 hours, 24 hours, and 7 days post-irradiation. Statistical analysis was performed using repeated measures ANOVA and Tukey's compromise post-hoc test with a significance level of p<0.05. Results: For both DCBRCs, at 0.5 hours post-irradiation, the 20 s and 40 s methods showed the highest KHN at depth of 0.5 mm. The 40 s method showed significantly higher KHN than the 20 s method at all depths of cavity and post-irradiation times, except UCE at depth of 0.5 mm (p<0.05). The 120 s method did not result in significantly different KHN at all depths of cavity and post-irradiation times (p>0.05). In DCP, and not UCE, at 24 hours and 7 days post-irradiation, the B+20 s method showed significantly higher KHN at all depths of cavity, except the depth of 0.5 mm (p<0.05). Conclusion: KHN depends on the light-exposure method, use of bonding agent, depth of cavity, post-irradiation time, and material brand. Based on the microhardness behavior, DCBRCs are preferably prepared by the effective exposure method, when used for a greater depth of cavity. .
Descritores: Resinas Compostas/efeitos da radiação
Testes de Dureza
Cura Luminosa de Adesivos Dentários/métodos
Cimentos de Resina/efeitos da radiação
-Análise de Variância
Resinas Compostas/química
Teste de Materiais
Processos Fotoquímicos/efeitos da radiação
Polimerização/efeitos da radiação
Reprodutibilidade dos Testes
Cimentos de Resina/química
Propriedades de Superfície/efeitos da radiação
Fatores de Tempo
Tipo de Publ: Estudo de Avaliação
Responsável: BR1.1 - BIREME


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Id: lil-696995
Autor: Collares, Fabricio Mezzomo; Portella, Fernando Freitas; Leitune, Vicente Castelo Branco; Samuel, Susana Maria Werner.
Título: Discrepancies in degree of conversion measurements by FTIR
Fonte: Braz. oral res;28(1):9-15, Jan-Feb/2014. tab, graf.
Idioma: en.
Resumo: The purpose of this study was to evaluate the influence of the internal standard peak on the measured degree of conversion (DC) for methacrylate-based resins analyzed by Fourier-transform infrared spectroscopy (FTIR). The influence of different baseline measurement methods was also determined. Different blends were prepared, mixing BisGMA/BisEMA and BisGMA/TEGDMA at proportions of 0% to 100%, in weight. Camphoroquinone and ethyl-4-dimethylamino-benzoate were used to permit the light activation of blends. Degree of conversion was evaluated using FTIR equipped with an attenuated total reflectance (ATR) device. Samples were dispensed onto ATR crystal and light activated for 40 s. The DC was calculated by relating the height of the peak 1637 cm-1 to the intensity of different internal standard peaks (1715, 1608, or 1582 cm-1), measured using two different baseline methods, before and after polymerization. Data were compared by ANOVA at 5% significance. The relationship between DC and monomer ratio was obtained by regression analysis. Double-bond conversion ranged from 32.75% to 78.50% for BisGMA/BisEMA blends, and from 32.75% to 76.22% for BisGMA/TEGDMA blends. For the BisGMA/BisEMA blends, the DC showed a linear association with the composition of the comonomer blends, independent of the internal standard peak and baseline method used. In contrast, the trends in DC for BisGMA/TEGDMA blends were different for each method of measurement. The internal standard peaks and measurement baseline should be taken into account when using FTIR to calculate the DC of methacrylate-based resins, especially comonomer blends containing a high degree of monomers that lack aromatic rings.
Descritores: Bis-Fenol A-Glicidil Metacrilato/química
Cura Luminosa de Adesivos Dentários/métodos
Metacrilatos/química
Polimerização
Polietilenoglicóis/química
Ácidos Polimetacrílicos/química
-Análise de Variância
Teste de Materiais
Processos Fotoquímicos
Valores de Referência
Análise de Regressão
Espectroscopia de Infravermelho com Transformada de Fourier
Fatores de Tempo
Tipo de Publ: Estudo de Avaliação
Research Support, Non-U.S. Gov't
Responsável: BR1.1 - BIREME


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Id: lil-685418
Autor: Brazilian Oral Research; Calgaro, Patricia Angelica Milani; Furuse, Adilson Yoshio; Correr, Gisele Maria; Ornaghi, Barbara Pick; Gonzaga, Carla Castiglia.
Título: Influence of the interposition of ceramic spacers on the degree of conversion and the hardness of resin cements
Fonte: Braz. oral res;27(5):403-409, Sep-Oct/2013. tab, graf.
Idioma: en.
Resumo: This study evaluated: I) the effect of photo-activation through ceramics on the degree of conversion (DC) and on the Knoop hardness (KHN) of light- and dual-cured resin cements; and II) two different protocols for obtaining the spectra of uncured materials, to determine the DC of a dual-cured resin cement. Thin films of cements were photo-activated through ceramics [feldspathic porcelain (FP); lithium disilicate glass-ceramics of low translucency (e.max-LT), medium opacity (e.max-MO) and high translucency (e.max-HT); glass-infiltrated alumina composite (IC) and polycrystalline zirconia (ZR)] with thicknesses of 1.5 and 2.0 mm. DC was analyzed by Fourier transform infrared (FTIR) spectroscopy. Two protocols were used to obtain the spectra of the uncured materials: I) base and catalyst pastes were mixed, and II) thin films of base and catalyst pastes were obtained separately, and an average was obtained. KHN assessment was performed with cylindrical specimens. The results were analyzed by ANOVA and Tukey's test (α= 0.05). The light-cured cement showed higher DC (61.9%) than the dual-cured cement (55.7%). The DC varied as follows: FP (65.4%), e.max-HT (65.1%), e.max-LT (61.8%), e.max-MO (60.9%), ZR (54.8%), and IC (44.9%). The light-cured cement showed lower KHN (22.0) than the dual-cured (25.6) cement. The cements cured under 1.5 mm spacers showed higher KHN (26.2) than when polymerized under 2.0 mm ceramics (21.3). Regarding the two protocols, there were significant differences only in three groups. Thus, both methods can be considered appropriate. The physical and mechanical properties of resin cements may be affected by the thickness and microstructure of the ceramic material interposed during photo-activation.
Descritores: Cerâmica/química
Cura Luminosa de Adesivos Dentários/métodos
Polimerização
Cimentos de Resina/química
-Análise de Variância
Testes de Dureza
Teste de Materiais
Processos Fotoquímicos
Valores de Referência
Cimentos de Resina/efeitos da radiação
Espectroscopia de Infravermelho com Transformada de Fourier
Fatores de Tempo
Limites: Humanos
Tipo de Publ: Estudo de Avaliação
Responsável: BR1.1 - BIREME


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Id: lil-673239
Autor: Brazilian Oral Research; Ferla, Juliana de Oliveira; Rodrigues, José Augusto; Arrais, César Augusto Galvão; Aranha, Ana Cecília Correa; Cassoni, Alessandra.
Título: Influence of photo-activation source on enamel demineralization around restorative materials
Fonte: Braz. oral res;27(3):286-292, May-Jun/2013. tab, graf.
Idioma: en.
Projeto: FAPESP.
Resumo: This study evaluated the effects of the photoactivation source and restorative material on the development of caries-like lesions on human enamel after an in vitro pH challenge. Enamel cavities were prepared in 36 blocks, which were assigned to two groups according to the restorative material: resin-modified glass ionomer (RMGI) and composite resin (CR). Samples were exposed to quartz-tungsten-halogen lamp, argon-ion laser, or light-emitting diode (n = 6). The Knoop microhardness (KHN) values of the top surface of all materials were evaluated. Restored enamel blocks were thermocycled and subjected to 10 demineralization-remineralization cycles at 37°C. KHN analysis of the superficial enamel was performed by four indentations located 100 mm from the restoration margin. The material KHN was not affected by the photoactivation source. No significant difference in KHN was noted between CR and RMGI. The enamel surface around RMGI exhibited a higher KHN (272.8 KHN) than the enamel around CR (93.3 KHN), regardless of the photoactivation source. Enamel demineralization around the dental restoration was not influenced by the photoactivation source. Less enamel demineralization was observed around the RMGI than around the CR restoration.
Descritores: Luzes de Cura Dentária
Resinas Compostas/efeitos da radiação
Esmalte Dentário/efeitos da radiação
Cimentos de Ionômeros de Vidro/efeitos da radiação
Desmineralização do Dente/etiologia
-Análise de Variância
Resinas Compostas/química
Restauração Dentária Permanente
Cimentos de Ionômeros de Vidro/química
Testes de Dureza
Teste de Materiais
Processos Fotoquímicos
Propriedades de Superfície/efeitos da radiação
Fatores de Tempo
Limites: Humanos
Tipo de Publ: Estudo de Avaliação
Research Support, Non-U.S. Gov't
Responsável: BR1.1 - BIREME


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Borsatto, Maria Cristina
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Id: lil-595649
Autor: Pinto, Corina Maia de Souza; Ferreira, José Tarcísio Lima; Matsumoto, Mírian Aiko Nakane; Borsatto, Maria Cristina; Silva, Raquel Assed Bezerra da; Romano, Fábio Lourenço.
Título: Evaluation of different LED light-curing devices for bonding metallic orthodontic brackets
Fonte: Braz. dent. j;22(3):249-253, 2011. ilus, tab.
Idioma: en.
Resumo: The aim of this study was to assess the influence of different light-emitting diodes (LED) light-curing devices for bonding orthodontic brackets, using the shear bond strength and analysis of adhesive remnant index (ARI). Crowns from 60 bovine incisors received brackets bonded with Transbond XT. Specimens were divided into 4 groups (n=15) according to the light-curing procedures: HL = control, halogen light; OR = Ortholux LED; UL = Ultraled XP, and RD = Radii LED. All light-curing procedures were performed for 40 s. Shear bond strength test was evaluated using an universal testing machine at a crosshead speed of 0.5 mm/min. Data were analyzed statistically by ANOVA and Tukey's test. The ARI scores were evaluated with a stereoscopic magnifying glass and analyzed statistically by Kruskal-Wallis test. A significance level of 5 percent was set for all analyses. Shear bond strength means in MPa and standard deviations were 9.82 (3.28), 12.70 (3.35), 9.04 (2.80) and 11.22 (2.36) for HL, OR, UL and RD, respectively. OR presented the highest shear bond strength mean value. HL differed significantly (p<0.05) from Groups OR and RD. However, these groups did not differ significantly from each other (p>0.05). Regarding the ARI scores, no statistically significant difference was observed (p>0.05) among the groups. In conclusion, Ortholux LED and Radii LED units provided the highest values of bracket adhesive strength.

O objetivo deste estudo foi avaliar a influência de diferentes aparelhos de luz tipo LED na colagem de bráquetes ortodônticos, através do teste de resistência ao cisalhamento e do Índice de Remanescente do Adesivo (IRA). Coroas de 60 incisivos bovinos receberam a colagem de bráquetes com compósito Transbond XT. A amostra foi dividida em 4 grupos (n=15) de acordo com os seguintes tipos de fotoativação: HL: controle, luz halógena; OR= Ortholux LED; UL= Ultraled XP e RD= Radii LED. Todas as fotoativações foram realizadas por 40 s. O teste de resistência ao cisalhamento foi realizado em máquina universal de ensaios mecânicos à velocidade de 0,5 mm/min. Os dados foram analisados estatisticamente pelo ANOVA e teste de Tukey. Os escores do IRA foram avaliados em lupa estereoscópica e analisados estatisticamente pelo teste de Kruskal-Wallis. O nível de significância de 5 por cento foi adotado para todas as análises. Os valores médios (MPa) e o desvio-padrão do teste de resistência ao cisalhamento foram 9,82 (3,28), 12,70 (3,35), 9,04 (2,80) e 11,22 (2,36) para o grupo HL, OR, UL e RD, respectivamente. O grupo OR apresentou os maiores valores médios de resistência ao cisalhamento. O grupo HL diferiu significativamente (p<0,05) dos grupos OR e RD. Entretanto, este dois grupos não diferiram estatisticamente entre si (p>0,05). Quanto ao escores do IRA, nenhuma diferença estatística significante foi observada (p>0,05) entre os grupos. Concluiu-se que as unidades de luz Ortholux LED e Radii LED proporcionaram maiores valores de resistência adesiva aos bráquetes.
Descritores: Luzes de Cura Dentária/classificação
Colagem Dentária
Ligas Dentárias/química
Braquetes Ortodônticos
-Adesividade
Condicionamento Ácido do Dente/métodos
Esmalte Dentário/anatomia & histologia
Análise do Estresse Dentário/instrumentação
Teste de Materiais
Processos Fotoquímicos
Polimerização
Ácidos Fosfóricos/química
Cimentos de Resina/química
Resistência ao Cisalhamento
Estresse Mecânico
Propriedades de Superfície
Fatores de Tempo
Limites: Animais
Bovinos
Tipo de Publ: Estudo de Avaliação
Responsável: BR1.1 - BIREME



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BIREME/OPAS/OMS - Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde