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Id: biblio-1051258
Autor: Chacón de la Iglesia, Johanna; Alvarez, Nilda María del Rosario; Zamudio, María Eugenia.
Título: Adhesión posclareamiento y el efecto de la aplicación de antioxidantes / Postbleaching bonding and the effect of applying antioxidants
Fonte: Rev. Ateneo Argent. Odontol;59(2):21-25, 2018.
Idioma: es.
Resumo: Con el avance en las técnicas de blanqueamiento dental, el advenimiento de nuevos biomateriales capaces de lograr resultados estéticos aceptables por los pacientes; sabiendo que en la operatoria dental muchos autores priorizan iniciar dicho tratamiento restaurador con el aclareamiento dental. Como consecuencia de este último, se ha demostrado que puede producir alteraciones en la adhesión de las resinas compuestas al esmalte dental, proceso dependiente de la concentración residual de radicales libres de oxígeno en la superficie y subsuperficie del esmalte por la degradación del peróxido de hidrogeno. Existe reducción en la fuerza de adhesión del esmalte blanqueado cuando el procedimiento adhesivo se realiza inmediatamente después de un blanqueamiento dental. Sin embargo, se sabe que los antioxidantes ayudan a inactivar los radicales libres de oxígeno residual para tratar de revertir las consecuencias físicoquímicas indeseables que producen los blanqueadores sobre la estructura dental y la adhesión. El objetivo de este trabajo de divulgación es analizar conceptos sobre la interacción entre adhesión posaclaramiento y de qué manera controlar esas interacciones (AU)

With the advancement in teeth whitening techniques, the advent of new biomaterials able to achieve aesthetic results acceptable to patients; knowing that in dental surgery many authors prioritize initiating said restorative treatment with dental clarification, and as a consequence of the latter it has been demonstrated that it can produce alterations in the adhesion of composite resins to dental enamel, a process dependent on the residual concentration of radicals free of oxygen on the surface and subsurface of the enamel by the degradation of hydrogen peroxide. There is a reduction in the adhesion strength of the bleached enamel when the adhesive process is performed immediately after tooth whitening. However, it is known that antioxidants help to inactivate free radicals of residual oxygen to try to reverse the undesirable physico-chemical consequences that bleaches produce on tooth structure and adhesion. The objective of this dissemination work is to analyze concepts on the interaction between post-clarification adhesion and treatments to control these interactions (AU)
Descritores: Clareamento Dental
Colagem Dentária
Esmalte Dentário/efeitos dos fármacos
-Teste de Materiais
Resinas Compostas/química
Peróxido de Hidrogênio
Antioxidantes/efeitos adversos
Responsável: AR29.1 - Biblioteca


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Id: biblio-1051325
Autor: Bueno, Carlos Roberto Emerenciano.
Título: Estudo de novos dispositivos, instrumentos e materiais empregados no tratamento endodôntico / Evaluation of new devices, instruments and materials used in endodontic treatment.
Fonte: Araçatuba; s.n; 2019. 72 p. ilus, tab.
Idioma: en; pt.
Tese: Apresentada a Universidade Estadual Paulista "Julio de Mesquita Filho". Faculdade de Odontologia de Araçatuba para obtenção do grau de Doutor.
Resumo: Introdução: O tratamento endodôntico visa manter ou restabelecer a saúde do periodonto através do preparo biomecânico, utilizando instrumentos de níqueltitânio automatizados e associados com insertos ultrassônicos para potencializar a ação dos irrigantes. Os materiais empregados na endodontia que permanecerão em contato com tecidos devem apresentar biocompatibilidade e preferencialmente ser biomineralizador, a fim de selar comunicações (fisiológicas/iatrogênicas), isolando o sistema de canais radiculares. Objetivos: 1- Avaliar a resistência à fadiga cíclica das limas reciprocantes Genius e EdgeFile X1 Small, comparados à lima WaveOne Gold Primary; 2- Avaliar a capacidade de limpeza de um inserto ultrassônico de níquel titânio em ativação da irrigação de forma contínua e passiva; 3- Avaliar a biocompatiblidade e biomineralização do cimento reparador MTA Flow. Material e Métodos: Para avaliar a resistência à fadiga cíclica dos sistemas Genius, EdgeFile e WaveOne Gold, 80 instrumentos foram utilizados (n=20), divididos em 4 grupos experimentais: Genius 25.04, Genius 30.04; EdgeFile X1 Small e Wave One Gold Primary, acionados em um canal artificial de aço inoxidável com ângulo de curvatura de 60o e raio de curvatura de 5 mm. O tempo decorrido da ativação do motor foi gravado em um cronômetro digital e parado assim que a fratura foi detectada. O número de ciclos até a falha (NCF) e o tempo para fratura (TF) foram calculados e os comprimentos dos segmentos fraturados medidos. Para avaliar a capacidade de limpeza do inserto ultrassônico, 45 prémolares inferiores, padronizados em 16 mm foram utilizados. A instrumentação foi realizada até lima 50.04 sob irrigação com hipoclorito de sódio e foram divididos em 3 grupos (n = 15) de acordo com a técnica de ativação final da solução irrigadora: irrigação convencional (IC) (passiva com pressão positiva/sucção concomitante) como controle; ativação ultrassônica passiva (PUI) e ativação ultrassônica contínua (CUI) do irrigante. Os três grupos tiveram os protocolos de ativação/irrigação final em soluções de hipoclorito de sódio e EDTA. As amostras foram clivadas, as imagens obtidas com microscopia eletrônica de varredura (MEV) e avaliadas quanto à capacidade de remoção da camada de smear layer no terço cervical, médio e apical, por um sistema de escores. Para análise biológica do material reparador MTA Flow, os materiais MTA Angelus e ProRoot MTA foram utilizados para comparação. Quarenta ratos receberam implantes subcutâneo de tubos de polietileno contendo os 3 materiais e tubo vazio como controle (n=10). Após 7, 15, 30 e 60 dias, os animais foram eutanasiados e os tubos removidos com o tecido conjuntivo circundantes. Infiltrado inflamatório e espessura da cápsula fibrosa foram avaliados histologicamente e indução da mineralização analisada por Von Kossa e sob luz polarizada. Os dados foram analisados com testes estatísticos específicos (p<5%). Resultados: Quanto à fadiga cíclica, os instrumentos EdgeFile X1 Small apresentaram maior resistência (NCF: 6175.74 ± 1608.99; TF: 1058.7 ± 275.82), seguido por ambos instrumentos Genius (p<0.05), de forma significativa comparados ao Waveone Gold Primary. O inserto de NiTi aumentou a limpeza, comparado com IC, principalmente no terço apical e CUI mostrou os melhores resultados (p<0.05). Nos resultados biológicos, MTA Angelus induziu a reação mais leve após 15 dias (p<0.05), seguido do MTA Flow. ProRoot MTA induziu uma inflamação severa no dia 7, reduzindo após 15 dias. Nenhuma diferença foi observada entre os materiais após 30 ou 60 dias (p>0.05). Estruturas coradas por Von Kossa e birrefringentes foram positivas para todos os materiais. Conclusões: 1- Os instrumentos EdgeFile X1 Small demonstraram maior resistência à fadiga cíclica que Genius e WaveOne Gold Primary. Ambos instrumentos Genius apresentaram resistência superior à WaveOne Gold Primary. 2- A ativação final do irrigante com o inserto NiTi melhorou a remoção de smear layer, com protocolo CUI superior à PUI ou IC. 3- O MTA Flow mostrou biocompatibilidade e induziu a biomineralização em todos os períodos observados(AU)

Introduction: The endodontic treatment aims to maintain or restore periodontal health through biomechanical instrumentation with nickel-titanium automatized instruments, associated with an ultrasonic tip to activate the irrigant, enhancing cleanness. Materials used in endodontics that will remain in contact with tissues, should demonstrate properties as biocompatibility and biomineralization ability, in order to seal communications (physiological/iatrogenic) isolating the root canal system. Objectives: 1- Evaluate the cyclic fatigue resistance of reciprocating Genius and EdgeFile X1 Small instruments compared to Waveone Gold Primary instruments; 2- Evaluate the cleaning effectiveness of a nickel-titanium ultrasonic tip in continuous and passive irrigant activation; 3-Evaluate the biocompatibility and biomineralization of MTA Flow repair cement. Materials and Methods: To evaluate the cyclic fatigue resistance of Genius, EdgeFile and WaveOne Gold, 80 instruments were used (n = 20), divided into 4 experimental groups: Genius 25.04, Genius 30.04; EdgeFile X1 Small and Wave One Gold Primary, reciprocating in a stainless steel artificial canal with a 60° angle of curvature and 5mm radius of curvature. The elapsed time of the motor activation was recorded in a digital timer and stopped as soon as the fracture was detected. The number of cycles to fracture (NCF) and time to fracture (TF) were calculated and the fractured segments lengths measured. To evaluate the ultrasonic tip cleanness capacity, forty-five mandibular premolars, standardized at 16 mm were used. The instrumentation was performed until file 50.04 under irrigation with sodium hypochlorite. The specimens were divided into 3 groups (n = 15) according to the final irrigant activation protocol: conventional irrigation (CI) (passive, with positive pressure/simultaneous aspiration) as control; passive ultrasonic irrigant activation (PUI) and continuous ultrasonic irrigant activation (CUI). All groups had the final activation / irrigation protocols with solutions of sodium hypochlorite and EDTA, standardized with same volume. Samples were sodium hypochlorite and EDTA, standardized with same volume. Samples were cleaved and images obtained through scanning electron microscopy (SEM) to assess smear layer removal in the cervical, middle and apical thirds, via a score system. To biologically analyze MTA Flow repair cement, MTA Angelus and ProRoot MTA cements were used as comparison. Forty rats received subcutaneous implants of polyethylene tubes containing the 3 cements and empty tube as control (n = 10). After days 7, 15, 30 and 60, the animals were euthanized and the tubes removed with the surrounding tissues. Inflammatory infiltrate and fibrous capsule thickness were histologically evaluated and mineralization induction assessed by Von Kossa staining and under polarized light. The data were analyzed with specific statistical tests (p<5%). Results: The cyclic fatigue test showed EdgeFile X1 Small with the highest resistance (NCF: 6175.74 ± 1608.99; TF: 1058.7 ± 275.82), followed by both Genius instruments (p<0.05). The nickel-titanium tip enhanced cleanness, compared to CI, mainly in the apical area, whereas CUI showed the best results (p<0.05). In the biological results, MTA Angelus induced the mildest reaction after 7 (p>0.05) and 15 days (p<0.05), followed by MTA Flow. ProRoot MTA induced severe inflammation on day 7, reducing after day 15 (p>0.05). No difference was observed after 30 or 60 days (p>0.05). Von Kossa staining and birefringents structures were positive for all materials. Conclusion: 1- EdgeFile X1 Small instruments demonstrated superior cyclic fatigue resistance than Genius and WaveOne Gold Primary. In addition, both Genius instruments showed superior resistance than WaveOne Gold Primary. 2- The final irrigant activation with the NiTi tip improved smear layer removal, with CUI protocol superior to PUI or CI. 3 - MTA Flow showed biocompatibility and induced biomineralization in all observed periods(AU)
Descritores: Tratamento do Canal Radicular
Teste de Materiais
-Ultrassom
Materiais Biocompatíveis
Ratos Wistar
Endodontia
FRONTAL BONEABDOMINAL INJURIES
Inflamação
Limites: Ratos
Responsável: BR186.1 - Biblioteca Honório Monteiro
BR186.1


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Id: biblio-975614
Autor: Pickens, Adam W; Robertson, Lakshmi Dakuri; Smith, Matthew Lee; Zheng, Qi; Song, Sejun.
Título: Headphone Evaluation for App-Based Automated Mobile Hearing Screening
Fonte: Int. arch. otorhinolaryngol. (Impr.);22(4):358-363, Oct.-Dec. 2018. tab, graf.
Idioma: en.
Resumo: Abstract Introduction With the need for hearing screenings increasing across multiple populations, a need for automated options has been identified. This research seeks to evaluate the hardware requirements for automated hearing screenings using a mobile application. Objective Evaluation of headphone hardware for use with an app-based mobile screening application. Methods For the purposes of this study, hEAR, a Bekesy-based mobile application designed by the research team, was compared with pure tone audiometric tests administered by an audiologist. Both hEAR and the audiologist's test used 7 frequencies (125 Hz, 250 Hz, 500 Hz, 1,000 Hz, 2000 Hz, 4,000 Hz and 8,000 Hz) adopting four different sets of commercially available headphones. The frequencies were regarded as the independent variable, whereas the sound pressure level (in decibels) was the dependent variable. Thirty participants from a university in Texas were recruited and randomly assigned to one of two groups, whose only difference was the order in which the tests were performed. Data were analyzed using a generalized estimating equation model at α = 0.05. Results Findings showed that, when used to collect data with the mobile app, both the Pioneer HDJ-2000 (Pioneer, Bunkyo, Tokyo, Japan) (p> 0.05) and the Sennheiser HD280 Pro (Sennheiser, Wedemark, Hanover, Germany) (p> 0.05) headphones presented results that were not statistically different from the audiologist's data across all test frequencies. Analyses indicated that both headphones had decreased detection probability at 4kHz and 8kHz, but the differences were not statistically significant. Conclusion Data indicate that a mobile application, when paired with appropriate headphones, is capable of reproducing audiologist-quality data.
Descritores: Aplicativos Móveis
Testes Auditivos/instrumentação
Testes Auditivos/métodos
-Audiometria de Tons Puros
Teste de Materiais
Reprodutibilidade dos Testes
Limites: Seres Humanos
Masculino
Feminino
Adulto
Meia-Idade
Tipo de Publ: Estudo Comparativo
Estudos de Avaliação
Responsável: BR66.1 - Divisão de Biblioteca e Documentação


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Czeczko, Nicolau Gregori
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Id: biblio-827652
Autor: Varella, Paola Zarur; Czeczko, Nicolau Gregori; Prestes, Manoel Alberto; Czeczko, Alexandre Eduardo Augustin; Fagundes, Marília da Cruz; Petisco, Roberta Dombroski.
Título: Ventral abdominal wall defect correction in rats with contaminated meshes
Fonte: Acta cir. bras;31(10):680-688, Oct. 2016. graf.
Idioma: en.
Resumo: ABSTRACT PURPOSE: To investigate whether there is a difference between Marlex(r) and Dynamesh PP-light Marlex(r) meshes, in the abdominal wall defect correction, on rats in contaminated surgical site. METHODS: Twenty-eight Wistar rats were divided into two groups of 14, and four subgroups of seven animals. All subgroups underwent similar surgical procedure. One group received the mesh Marlex(r) and the other Dynamesh PP-light(r) for correction of the defect. Before implanting, the meshes went through a contamination process, on which was used standard solution containing 10 UFC of Escherichia coli. Fragments of the animal's abdominal wall received macroscopic, microscopic and microbiological analysis. RESULTS: There was no statistical significance in the analysis of macroscopic variables. Accentuated inflammatory process was shown in all subgroups. The foreign body type reaction was mild in all subgroups, except Dynamesh(r)-14, which was moderate with no statistical significance. The microbiological analysis of the meshes was also similar between the subgroups. CONCLUSION: There was no difference between the meshes of Marlex(r) and Dynamesh PP-light(r) in the ventral abdominal wall defect correction on rats in contaminated surgical site.
Descritores: Polipropilenos/uso terapêutico
Telas Cirúrgicas/microbiologia
Herniorrafia/métodos
Hérnia Ventral/cirurgia
Hérnia Ventral/microbiologia
-Deiscência da Ferida Operatória
Fatores de Tempo
Materiais Biocompatíveis
Índice de Gravidade de Doença
Teste de Materiais
Distribuição Aleatória
Reprodutibilidade dos Testes
Ratos Wistar
Escherichia coli/crescimento & desenvolvimento
Infecções Intra-Abdominais/microbiologia
Infecções Intra-Abdominais/patologia
Hérnia Ventral/patologia
Necrose
Limites: Animais
Masculino
Tipo de Publ: Estudo Comparativo
Responsável: BR1.1 - BIREME


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Id: lil-783797
Autor: Biondo-Simões, Maria de Lourdes Pessole; Morais, Camila Gomes de; Tocchio, Anna Flávia Zonato; Miranda, Renata Augusta de; Moura, Paula Almeida Pamponet; Colla, Kelly; Robes, Rogério Ribeiro; Ioshii, Sérgio Ossamu; Tomasich, Flávio Daniel Saavedra.
Título: Characteristics of the fibroplasia and collagen expression in the abdominal wall after implant of the polypropylene mesh and polypropylene/polyglecaprone mesh in rats
Fonte: Acta cir. bras;31(5):294-299, May 2016. graf.
Idioma: en.
Resumo: ABSTRACT PURPOSE: To compare fibroplasia and the resistance of the abdominal wall when polypropylene meshes and polypropylene/poliglecaprone are used. METHODS: Seventy-seven male Wistar rats were divided into three groups: Control Group (for resistance); Group E (polypropylene mesh); and Group U (polypropylene/poliglecaprone mesh). The animals in Groups E and U had a standard muscular and aponeurotic defect, with integral peritoneum, and correction with the mesh. Measurements were taken 4, 7, 14, 28 and 56 days after surgery. The resistance, and collagen density were studied. RESULTS: Resistance on the 56th day was similar in both meshes. The gain in resistance described an ascending curve for the polypropylene mesh and was irregular in the case of the polypropylene/poliglecaprone. Fibroplasia showed a gain in type I and type III collagen in both groups (p<0.001). Collagen III stabilized in the 14th day and collagen I continued to ascend. CONCLUSIONS: The gain in resistance of the polypropylene mesh is regular and ascending, whereas the polypropylene/poliglecaprone is not regular. The final resistance of both meshes is similar; the collagen density increases over time, and show the same inflammatory potential.
Descritores: Poliésteres/uso terapêutico
Polipropilenos/uso terapêutico
Colágeno/metabolismo
Parede Abdominal/cirurgia
Dioxanos/uso terapêutico
Hérnia Incisional/cirurgia
-Período Pós-Operatório
Resistência à Tração/fisiologia
Teste de Materiais/instrumentação
Ratos Wistar
Modelos Animais
Colágeno Tipo I/metabolismo
Colágeno Tipo III/metabolismo
Hérnia Incisional/fisiopatologia
Hérnia Incisional/metabolismo
Limites: Animais
Masculino
Responsável: BR1.1 - BIREME


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Alberti, Luiz Ronaldo
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Id: biblio-886183
Autor: Garcia, Diego Paim Carvalho; Santos Neto, Clarissa; Nunes, Cristiana Buzelin; Buzelin, Marcelo Araújo; Petroianu, Andy; Figueiredo, Luiza Ohasi de; Motta, Andreia Souto da; Gaspar, Cristiane de Barros; Alberti, Luiz Ronaldo.
Título: Comparative study of intraperitoneal adhesions related to light-weight polypropylene mesh and type I polymerized and purified bovine collagen coated light-weight polypropylene mesh in rabbits
Fonte: Acta cir. bras;32(11):903-912, Nov. 2017. tab, graf.
Idioma: en.
Resumo: Abstract Purpose: To compare the effectiveness of light-weight polypropylene mesh coated with polymerized and purified bovine type I collagen (Surgidry HNB) in the treatment of abdominal wall defect and the degree of adhesion formation. Methods: Two types of polypropylene mesh were implanted after creation of defect measuring 6.0cm X 5.5cm in the anterior abdominal wall of 32 male New Zealand breed rabbits, divided in two groups (n = 32): (1) light-weigh macroporous polypropylene, (2) type I polymerized and purified bovine collagen coated light-weigh macroporous polypropylene. These animals were further accessed for adhesions, histological evaluation of inflammation and wall's thickness. Results: The percentage of the area adhered in group 1 (62.31 ± 16.6) was higher compared to group 2 (22.19 ± 14.57) (p <0.05). There was an association between the percentage of the covered area by adhesions and the type of adhesion, toughness and the scores obtained by the adhesion score by correlation analysis (p <0.05). There was no difference between the groups in any variables in relation to the degree of inflammation. Conclusion: The purified type I bovine collagen coated light-weigh polypropylene mesh showed to be effective in the repair of abdominal wall defects and reducing adhesion formation.
Descritores: Doenças Peritoneais/prevenção & controle
Polipropilenos
Telas Cirúrgicas
Colágeno Tipo I
Parede Abdominal/cirurgia
-Doenças Peritoneais
Próteses e Implantes
Teste de Materiais
Distribuição de Qui-Quadrado
Aderências Teciduais/patologia
Aderências Teciduais/prevenção & controle
Modelos Animais de Doenças
Limites: Animais
Masculino
Bovinos
Coelhos
Responsável: BR1.1 - BIREME


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Id: lil-797976
Autor: Lima, Jozely Francisca Mello; Maciel, Janaína Gomes; Hotta, Juliana; Vizoto, Ana Carolina Pero; Honório, Heitor Marques; Urban, Vanessa Migliorini; Neppelenbroek, Karin Hermana.
Título: Porosity of temporary denture soft liners containing antifungal agents
Fonte: J. appl. oral sci;24(5):453-461, Sept.-Oct. 2016. tab.
Idioma: en.
Projeto: FAPESP - São Paulo Research Foundation.
Resumo: ABSTRACT Incorporation of antifungals in temporary denture soft liners has been recommended for denture stomatitis treatment; however, it may affect their properties. Objective: To evaluate the porosity of a tissue conditioner (Softone) and a temporary resilient liner (Trusoft) modified by minimum inhibitory concentrations (MICs) of antifungal agents for Candida albicans biofilm. Material and Methods: The porosity was measured by water absorption, based on exclusion of the plasticizer effect. Initially, it was determined by sorption isotherms that the adequate storage solution for specimens (65×10×3.3 mm) of both materials was 50% anhydrous calcium chloride (S50). Then, the porosity factor (PF) was calculated for the study groups (n=10) formed by specimens without (control) or with drug incorporation at MICs (nystatin: Ny-0.032 g, chlorhexidine diacetate: Chx-0.064 g, or ketoconazole: Ke-0.128 g each per gram of soft liner powder) after storage in distilled water or S50 for 24 h, seven and 14 d. Data were statistically analyzed by 4-way repeated measures ANOVA and Tukey's test (α=.05). Results: Ke resulted in no significant changes in PF for both liners in water over 14 days (p>0.05). Compared with the controls, Softone and Trusoft PFs were increased at 14-day water immersion only after addition of Ny and Chx, and Chx, respectively (p<0.05). Both materials showed no significant changes in PF in up to 14 days of S50 immersion, compared with the controls (p>0.05). In all experimental conditions, Softone and Trusoft PFs were significantly lower when immersed in S50 compared with distilled water (p<0.05). Conclusions: The addition of antifungals at MICs resulted in no harmful effects for the porosity of both temporary soft liners in different periods of water immersion, except for Chx and Ny in Softone and Chx in Trusoft at 14 days. No deleterious effect was observed for the porosity of both soft liners modified by the drugs at MICs over 14 days of S50 immersion.
Descritores: Ácidos Polimetacrílicos/química
Resinas Acrílicas/química
Reembasadores de Dentadura
Prótese Parcial Temporária
Antifúngicos/química
-Propriedades de Superfície
Fatores de Tempo
Teste de Materiais
Cloreto de Cálcio/química
Água/química
Testes de Sensibilidade Microbiana
Clorexidina/química
Nistatina/química
Reprodutibilidade dos Testes
Análise de Variância
Porosidade
Biofilmes/efeitos dos fármacos
Imersão
Cetoconazol/química
Tipo de Publ: Estudos de Avaliação
Responsável: BR1.1 - BIREME


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Id: lil-797974
Autor: Lim, Kiatlin; Yap, Adrian U-Jin; Agarwalla, Shruti Vidhawan; Tan, Keson Beng-Choon; Rosa, Vinicius.
Título: Reliability, failure probability, and strength of resin-based materials for CAD/CAM restorations
Fonte: J. appl. oral sci;24(5):447-452, Sept.-Oct. 2016. tab, graf.
Idioma: en.
Projeto: National University of Singapore.
Resumo: ABSTRACT Objective: This study investigated the Weibull parameters and 5% fracture probability of direct, indirect composites, and CAD/CAM composites. Material and Methods: Discshaped (12 mm diameter x 1 mm thick) specimens were prepared for a direct composite [Z100 (ZO), 3M-ESPE], an indirect laboratory composite [Ceramage (CM), Shofu], and two CAD/CAM composites [Lava Ultimate (LU), 3M ESPE; Vita Enamic (VE), Vita Zahnfabrik] restorations (n=30 for each group). The specimens were polished, stored in distilled water for 24 hours at 37°C. Weibull parameters (m= modulus of Weibull, σ0= characteristic strength) and flexural strength for 5% fracture probability (σ5%) were determined using a piston-on-three-balls device at 1 MPa/s in distilled water. Statistical analysis for biaxial flexural strength analysis were performed either by both one-way ANOVA and Tukey's post hoc (α=0.05) or by Pearson's correlation test. Results: Ranking of m was: VE (19.5), LU (14.5), CM (11.7), and ZO (9.6). Ranking of σ0 (MPa) was: LU (218.1), ZO (210.4), CM (209.0), and VE (126.5). σ5% (MPa) was 177.9 for LU, 163.2 for CM, 154.7 for Z0, and 108.7 for VE. There was no significant difference in the m for ZO, CM, and LU. VE presented the highest m value and significantly higher than ZO. For σ0 and σ5%, ZO, CM, and LU were similar but higher than VE. Conclusion: The strength characteristics of CAD/ CAM composites vary according to their composition and microstructure. VE presented the lowest strength and highest Weibull modulus among the materials.
Descritores: Zircônio/química
Projeto Auxiliado por Computador
Silicatos/química
Dióxido de Silício/química
Resinas Compostas/química
Cimentos de Resina/química
Tocoferóis/química
Restauração Dentária Permanente/métodos
-Valores de Referência
Estresse Mecânico
Propriedades de Superfície
Resistência à Tração
Fatores de Tempo
Fraturas dos Dentes
Teste de Materiais
Microscopia Eletrônica de Varredura
Probabilidade
Reprodutibilidade dos Testes
Análise de Variância
Maleabilidade
Falha de Restauração Dentária
Tipo de Publ: Estudos de Avaliação
Responsável: BR1.1 - BIREME


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Silva, Léa Assed Bezerra da
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Id: lil-792602
Autor: LONGO, Daniele Lucca; PAULA-SILVA, Francisco Wanderley Garcia; FACCIOLI, Lucia Helena; GATÓN-HERNÁNDEZ, Patrícia Maria; QUEIROZ, Alexandra Mussolino de; SILVA, Léa Assed Bezerra da.
Título: Cytotoxicity and cytokine expression induced by silorane and methacrylate-based composite resins
Fonte: J. appl. oral sci;24(4):338-343, July-Aug. 2016. tab, graf.
Idioma: en.
Projeto: São Paulo Research Foundation; . CNPq.
Resumo: ABSTRACT The successful use of composite resins in Dentistry depends on physicochemical properties, but also on the biological compatibility of resins, because of the close association between pulp and dentin. Objective The aim of this study was to evaluate cytotoxicity and cytokine production induced by light-cured or non-light-cured methacrylate-based and silorane composite resins in RAW 264.7 macrophages. Material and Methods Cells were stimulated with the extracts from light-cured or non-light-cured composite resins. After incubation for 24 h, cytotoxicity was assessed with the lactate dehydrogenase (LDH) and methyl thiazolyl tetrazolium (MTT) assays, and total protein was quantified using the Lowry method. TNF-α detection was examined with an enzyme-linked immunosorbent assay (ELISA) conducted with cell supernatants after cell stimulation for 6, 12, and 24 h. Data were analyzed using one-way analysis of variance (ANOVA) and Tukey’s post hoc test (α=0.05). Results KaloreTM and FiltekTM Silorane were cytotoxic with or without light curing (p<0.05) after 24 h of incubation. KaloreTM stimulated the early production of TNF-α in comparison with control (p<0.05), whereas FiltekTM Silorane did not affect TNF-α levels after 6 and 12 h (p>0.05). However, after 24 h FiltekTM Silorane inhibited the production of TNF-α (p<0.05). Conclusions KaloreTM and FiltekTM Silorane were cytotoxic regardless of light curing. The extract obtained from KaloreTM after 15 days of incubation stimulated the production of TNF-α, unlike that obtained from FiltekTM Silorane.
Descritores: Fator de Necrose Tumoral alfa/análise
Resinas Compostas/toxicidade
Resinas de Silorano/toxicidade
Metacrilatos/toxicidade
-Valores de Referência
Fatores de Tempo
Teste de Materiais
Ensaio de Imunoadsorção Enzimática
Linhagem Celular
Sobrevivência Celular/efeitos dos fármacos
Sobrevivência Celular/efeitos da radiação
Células Cultivadas
Reprodutibilidade dos Testes
Resinas Compostas/efeitos da radiação
Luzes de Cura Dentária
Resinas de Silorano/efeitos da radiação
L-Lactato Desidrogenase
Metacrilatos/efeitos da radiação
Limites: Animais
Camundongos
Tipo de Publ: Estudos de Avaliação
Responsável: BR1.1 - BIREME


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Id: lil-792600
Autor: DOI, Kazuya; KUBO, Takayasu; MAKIHARA, Yusuke; OUE, Hiroshi; MORITA, Koji; OKI, Yoshifumi; KAJIHARA, Shiho; TSUGA, Kazuhiro.
Título: Osseointegration aspects of placed implant in bone reconstruction with newly developed block-type interconnected porous calcium hydroxyapatite
Fonte: J. appl. oral sci;24(4):325-331, July-Aug. 2016. tab, graf.
Idioma: en.
Projeto: Japan Society for the Promotion of Science.
Resumo: ABSTRACT Artificial bone has been employed to reconstruct bone defects. However, only few reports on implant placement after block bone grafting exist. Objectives The purpose of this study was to evaluate the osseointegration of dental implant in bone reconstructions with interconnected porous calcium hydroxyapatite (IP-CHA). Material and Methods The IP-CHA cylinders (D; 4.3 mm, H; 10.0 mm) were placed into bone sockets in each side of the femurs of four male dogs. The IP-CHA on the right side was a 24-week sample. Twelve weeks after placement, a titanium implant was placed into a socket that was prepared in half of the placed IP-CHA cylinder on the right side. On the left side, another IP-CHA cylinder was placed as a 12-week sample. After another 12 weeks, the samples were harvested, and the bone regeneration and bone-implant contact (BIC) ratios were measured. Results New bone formation area was superior in the 24-week IP-CHA compared with the 12-week IP-CHA. BIC was not significantly different between IP-CHA and the parent sites. Osseointegration was detected around the implant in IP-CHA-reconstructed bone. Conclusion Our preliminary results suggest that IP-CHA may be a suitable bone graft material for reconstructing bones that require implant placement.
Descritores: Osseointegração/efeitos dos fármacos
Transplante Ósseo/métodos
Durapatita/farmacologia
Substitutos Ósseos/farmacologia
Implantação Dentária Endo-Óssea/métodos
-Propriedades de Superfície
Fatores de Tempo
Titânio/química
Teste de Materiais
Microscopia Eletrônica de Varredura
Reprodutibilidade dos Testes
Planejamento de Prótese Dentária
Implantes Experimentais
Fêmur/cirurgia
Limites: Animais
Masculino
Cães
Tipo de Publ: Estudos de Avaliação
Responsável: BR1.1 - BIREME



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