Estudo comparativo da eficacia de dois adesivos dentinarios e um cimento de ionomero de vidro empregados na adesão do amalgama a dentina

Pós-graduação em Odontologia Restauradora - ICT

Efeito do pré-tratamento da dentina bovina na resistência ao cisalhamento de um cimento de ionômero de vidro resina modificado

Pós-graduação em Odontologia Restauradora - ICT

Avaliação laboratorial da resistência ao cisalhamento de discos de porcelana e de um polímero de vidro cimentados à dentina bovina com o emprego de cimentos adesivos

Pós-graduação em Odontologia Restauradora - ICT

Efeito do laser Nd:Yag no pré-tratamento dentinário e selamento marginal, em restaurações de cimento de ionômero de vidro resina modificado

Pós-graduação em Odontologia Restauradora - ICT

Anatomização de pinos de fibra de vidro: estudo de propriedades mecânicas na interface restauradora adesiva

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Análise química, citotoxicidade e biocompatibilidade de cimentos de ionômero de vidro

Objetivo: O presente trabalho, dividido em três estudos, teve como objetivo geral identificar e quantificar a liberação de componentes e avaliar a citotoxicidade e a biocompatibilidade de cimentos de ionômero de vidro (CIVs). Método: Para o estudo 1, extratos dos CIVs Vitrebond (VB), Fuji Lining LC (FL), Vitremer (VM), Fuji II LC (FII), Ketac Fil Plus (KF) e Ketac Molar Easymix (KM) foram obtidos pela imersão de corpos-de-prova em meio de cultura celular (DMEM). Esses extratos (n=9 por grupo) foram analisados por eletrodo específico quanto à presença de flúor e por espectrometria de absorção atômica quanto à presença de alumínio e zinco. HEMA e iodobenzeno foram identificados por CG/EM (n=6). Para o estudo 2, células MDPC-23 foram colocadas em contato com os extratos dos CIVs por 24 horas. Em seguida, foram avaliadas a atividade da desidrogenase succínica (SDH) (n=8), a produção de proteína total (PT) (n=8), a atividade da fosfatase alcalina (FAL) (n=8) e a morfologia celular (n=2). Para o estudo 3, tubos de polietileno (n=24 por grupo) foram preenchidos com os CIVs e implantados no tecido subcutâneo de 42 ratos. Como grupo controle foi utilizada a guta-percha. Após 7 ou 15 dias de pós-operatório, metade dos espécimes de cada grupo e período (n=6) foi preparada para análise histológica, e os demais (n=6) para análise da expressão de genes que codificam para IL-1? e TNF-?. Resultados: Os extratos de todos os CIVs apresentaram uma concentração de flúor significativamente maior do que o meio de cultura DMEM (controle), tendo o VB liberado maior quantidade, estatisticamente significante, do que os demais CIVs. O VB foi, também, o único material que liberou quantidades relativamente altas de alumínio e de zinco. O HEMA foi identificado nos extratos de todos os CIVs modificados por resina (VB, FL, VM e FII), e o iodobenzeno... (Resumo completo, clicar acesso eletrônico abaixo)

Desenvolvimento e caracterização de compósitos de fibras naturais modificadas e híbridos: fibras da coroa do abacaxi/polipropileno e fibras da coroa do abacaxi/fibras de vidro/polipropileno

The concern with the environment preservation has done with that researchers as well as industries invest in the search for materials that come from renewable sources. Natural fibers, because they are ecologically correct and have low cost, have been studied as a possible substitute, even if partial, of synthetic fibers in the development of polymeric composites. In this context, the hybrid composites (natural/synthetic) increase considerably the range of application of natural composites. The auto industry, in its constant quest for good mechanical properties materials which are developed with sustainability, has in composites with hybrid reinforcement a very viable alternative. In the present work, the nature Crown pineapple fibers and nature Crown pineapple fibers treated with alkaline solution were studied in order to evaluate the influence of chemical treatment in its properties. For this techniques were used x-ray diffractometry, Thermogravimetry and Infrared Spectroscopy (FTIR). Composites have been developed using polypropylene, reinforced with pineapple fibers and pineapple fibers hybrids/glass fibres, both with levels of 5 and 10%. These composites were analyzed by Thermogravimetry techniques and tested by traction. The realization of this work indicated that although the chemical treatment did not affect the thermal stability of the fibers, caused an increase in crystallinity index fibers and decreased its hydrophilic. The tests performed on composite indicated that the composites process was suitable because it provided good dispersion of the polymer matrix. The addition of natural fibers from the pineapple's Crown, in a proportion of 10%, provided the greatest increase in modulus of elasticity (27%) when compared to the pure polymer

Sistema de monitoração de bloqueios tipo porta de vidro

Automatic video surveillance system has been a frequent topic of research due to the large number of promising applications. In this research, we developed a tracking and counting people system, as well as suspicious activities detector. The model tracks individual objects as they pass through the field of vision of the camera using vision algorithms to classify the activities of each person, and according to this features, detect dangerous situations. This dissertation includes a review of several techniques trying to develop a robust and low computacional costs system to be used in glass door barrier turnstiles avoiding fraud

Obtenção de rochas sintéticas a partir de resíduos de vidro comercial e pó de granito

Pós-graduação em Engenharia Mecânica - FEG

Propriedades antimicrobianas, físico-mecânicas e de liberação de fluoreto do cimento de ionômero de vidro associado ao hexametafosfato de sódio microparticulado e nanoparticulado

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação da aplicação de ondas de ultra-som sobre cimentos de ionômero de vidro: rugosidade superficial e dureza

The application of ultrasonic waves during the initial setting of the glass ionomer cements (GIC) has demonstrated increase of the cure speed, reduction of air bubbles and improves in some mechanical properties. The aim of this study was to evaluate the effect of the ultrasound on the microhardness and the superficial roughness in two GICs (FUJI IX GP (GC Corporation) and Ketac Molar EasyMix (3M ESPE)). Forty specimens were confectioned, twenty for evaluation of the superficial roughness and twenty for evaluation of the microhardness. Half of them received for thirty seconds the ultrasonic waves application. The readings of the roughness had been carried before and after the toothbrushing test. The twenty remaining specimens had been polished with abrasive sandpapers of decreasing granulations and submitted to the hardness test. The results, analyzed for the variance analysis (ANOVA) (p<0,05), had demonstrated increase of the hardness for all the groups with the application of ultrasonic waves, being bigger for the Ketac Molar EasyMix. The ultrasound application also caused significant reduction of the superficial roughness for the Ketac Molar EasyMix. After the toothbrushing test, this last property increased for all the materials. It could be concluded that the application of ultrasonic waves was effective in increasing the superficial hardness of the materials and that it improved the roughness of the Ketac Molar EasyMix before the toothbrushing test.

Desgaste e rugosidade superficial de um cimento de ionômero de vidro nanoparticulado

To compare the abrasion wear resistance and superficial roughness of different glass ionomer cements used as restorative materials, focusing on a new nanoparticulate material. Material and Method: Three glass ionomer cements were evaluated: Ketac Molar, Ketac N100 and Vitremer (3M ESPE, St. Paul, MN, USA), as well as the Filtek Z350 (3M ESPE, St. Paul, MN, USA). For each material were fabricated circular specimens (n=12), respecting the handling mode specified by the manufacturer, which were polished with sandpaper disks of decreasing grit. The wear was determined by the amount of mass (M) lost after brushing (10,000 cycles) and the roughness (Ra) using a surface roughness tester. The difference between the Minitial and Mfinal (ΔM) as well as beroughness of aesthetic restorative materials: an in vitro comparison. SADJ. 2001; 56(7): 316-20. 11. Yip HK, Peng D, Smales RJ. Effects of APF gel on the physical structure of compomers and glass ionomer cements. Oper. Dent. 2001; 26(3): 231-8. 12. Ma T, Johnson GH, Gordon GE. Effects of chemical disinfectants on the surface characteristics and color of denture resins. J Prosthet Dent 1997; 77(2): 197-204. 13. International organization for standardization. Technical specification 14569-1. Dental Materials – guidance on testing of wear resistance – PART I: wear by tooth brushing. Switzerland: ISO; 1999. 14. Bollen CML, Lambrechts P, Quirynen M. Comparison of surface roughness of oral hard materials to the threshold surface roughness for bacterial plaque retention: a review of the literature. Dent Mater.1997; 13(4): 258-9. 15. Kielbassa AM, Gillmann C, Zantner H, Meyer-Lueckel H, Hellwig E, Schulte-Mönting J. Profilometric and microradiographic studies on the effects of toothpaste and acidic gel abrasivity on sound and demineralized bovine dental enamel. Caries Res. 2005; 39(5): 380-6. 16. Tanoue N, Matsumara H, Atsuta M. Wear and surface roughness of current prosthetic composites after toothbrush/dentifrice abrasion. J Prosthet Dent. 2000; 84(1): 93-7. 17. Heath JR, Wilson HJ. Abrasion of restorative materials by toothpaste. J Oral Rehabil. 1976; 3(2): 121-38. 18. Frazier KB, Rueggeberg FA, Mettenburg DJ. Comparasion of wearresistance of class V restorative materials. J Esthet Dent. 1998; 10(6): 309-14. 19. Momoi Y, Hirosakil K, Kohmol A, McCabe JF. In vitro toothebrushdentifrrice abrasion of resin-modified glass ionomers. Dent Mater. 1997; 13(2): 82-8. 20. Turssi CP, Magalhães CS, Serra MC, Rodrigues Jr.AL. Surface roughness assessment of resin-based materials during brushing preceded by pHcycling simulations. Oper Dent. 2001; 26(6): 576-84. 21. Wang L, Cefaly DF, Dos Santos JL, Dos Santos JR, Lauris JR, Mondelli RF, et al. In vitro interactions between lactic acid solution and art glassionomer cements. J Appl Oral Sci. 2009; 17(4): 274-9. 22. Carvalho FG, Fucio SB, Paula AB, Correr GM, Sinhoreti MA, PuppinRontani RM. Child toothbrush abrasion effect on ionomeric materials. J Dent Child (Chic). 2008; 75(2): 112-6. 23. Coutinho E, Cardoso MV, De Munck J, Neves AA, Van Landuyt KL, Poitevin A, et al. Bonding effectiveness and interfacial characterization of a nano-filled resin-modified glass-ionomer. Dent Mater. 2009; 25(11): 1347-57. tween Rainitial and Rafinal (ΔRa) were also used for statistical analysis (α=0.05). Results: Except for the composite, significant loss of mass was observed for all glass ionomer cements and the ΔM was comparable for all of them. Significant increase in roughness was observed only for Vitremer and Ketac N100. At the end of the brushing cycle, just Vitremer presented surface roughness greater than the composite resin. Conclusion: All glass ionomer cements showed significant weight loss after 10,000 cycles of brushing. However, only Vitremer showed an increase of roughness greater than the Z350 resin, while the nanoparticulate cement Ketac N100 showed a smooth surface comparable to the composite.

Dureza e rugosidade superficial de cimentos de ionômero de vidro após ensaio de escovação

To evaluate the surface roughness and Vickers hardness of glass ionomer cements Ketac Molar® and Ketac Molar Easy Mix® (ESPE Dental AG) after brushing. Methods – After roughness and hardness tests of 14 specimens of each material, they were submitted to 30,000 brushing cycles and new analysis of roughness and hardness. Statistical analysis showed that there was no significant difference between the materials in relation to the initial roughness. Results – However, after brushing there was higher surface roughness for Ketac Molar Easy Mix®. For both materials, there was increase of hardness after brushing and the highest values were presented by Ketac Molar Easy Mix®. Conclusion – It can be concluded that, when choosing a glass ionomer cement for restoration it should be preferred to Ketac Molar, because it showed hardness similar to Ketac Molar Easy Mix, but it was less rough.

Resistência à tração diametral de cimentos de ionômero de vidro submetidos à aplicação de ondas de ultrassom

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influência da incorporação de nanopartículas de trimeta- fosfato de sódio associado ou não à clorexidina nas proprie- dades microbiológicas, físico-mecânicas e de redução da desmineralização de cimento de ionômero de vidro

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)