Obtenção e caracterização de compósitos nanoestruturados de poli(sulfeto de fenileno) reforçados com nanotubos de carbono

Pós-graduação em Engenharia Mecânica - FEG

Estudo da modificação superficial de fibras de carbono por meio de tratamentos a plasma para o aumento da adesão na interface de compósitos fibra de carbono/PPS

Pós-graduação em Engenharia Mecânica - FEG

Fadiga em compósitos 5HS carbono/epóxi processados via RTM: relação entre cargas axiais no plano e modos de delaminação

Pós-graduação em Engenharia Mecânica - FEG

Compósitos de nanocelulose / PHBV: manta microfibrilica por eletrofiação

Pós-graduação em Engenharia Mecânica - FEG

Resistência à tração de coroas de NiCr cimentadas sobre munhões de liga de titânio, com 4 diferentes tipos de cimentos

In this work of tensile strength was evaluated the efficacy of 4 cements (S. S. White zinc phoshate, Ketac Cem Easymix glass ionomer, RelyX Luting 2 composite resin/glass ionomer and Panavia 21 TC special acrylic resin) used to fix NiCr crowns to usinated titanium alloy abutments. Were used 40 abutments distributed in groups of 10 elements, to each material. The mechanical essays were developed at a MTS 810 universal machine, adjusted to a 0.5 mm/m velocity. The ANOVA applied to data pointed out the existence of significant differences between groups; the subsequent Tukey´s test (p<0.05) also detected significant differences, except at comparisons of phosphate versus RelyX and phosphate versus Ketac Cem. The better performance was presented by Panavia 21 (1,127.996 N); RelyX (478.197 N) showed itself similar only to phosphate (430.662 N), wich had a performance similar to that of Ketac Cem (227.705 N).

Análise comparativa da ação antimicrobiana dos cimentos endodônticos Acroseal, Sealapex e AH plus pós presa em biofilme de enterococcus faecalis

Pós-graduação em Ciência Odontólogica - FOA

Influência da diabetes mellitus na resposta tecidual e na capacidade de mineralização dos cimentos Sealapex, MTA Angelus e MTA Fillapex

Pós-graduação em Ciência Odontólogica - FOA

Otimização do processamento de partículas lead-free para aplicação em compósitos polímero/cerâmica com propriedades piezoelétrica e fotoluminescente

Pós-graduação em Química - IQ

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.

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.

Efeito das dimensões dos corpos de prova na resistência à flexão de compósitos restauradores

The aim of this study was to evaluate the influence of specimen size, in comparison with the ISO Standard, on the three point flexural strength of resin composite restorative materials Filtek Supreme and Filtek Z-250. Forty specimens were fabricated for each material with the following length, width and thickness measurements (n = 10): 1) 20 × 2 × 2 mm (ISO 4049); 2) 10 × 2 × 1 mm; 3) 10 × 1 × 1 mm; 4) 8 × 0.8 × 0.8 mm. The composites were inserted in a single increment into two-piece metal device and light-polymerized. The specimens were dry stored at 37 ± 1 °C and protected from light for 7 days. After this period, flexural strength was measured by three-point flexure test using MTS 810 equipment, with a load cell of 10 kN at a speed of 0.5 mm/min. For the evaluated sizes, the results showed significant variability (p = 0.00) with values when compared with the ISO Standard (116.700 MPa), being statistically higher for the test specimens measuring 10 × 1 × 1 mm (142.530 MPa), similar for those of 10  ×  2  ×  1  mm (115.815 MPa) and lower for those of 8 × 0.8 × 0.8 mm (86.650 MPa). There was statistical equality (p = 0.08) for the studied composites (Filtek Supreme, 125.270 MPa; Filtek Z-250, 108.130 MPa). Specimens measuring 10 × 2 × 1 mm provided flexural strength values equivalent to those obtained in the sizes recommended by the ISO 4049 standard, with lower consumption of material, energy and time.

Matriz Bertholdo/Ricci/Barrotte (BRB): uma simplificação de técnica para obtenção de guia de estratificação com compósitos

Advanced Layering composite resins can be facilitated by a technique called "Lingual Matrix", where a guide is made of elastomer by molding a previously waxed tooth or sculped in an intraoral test drive restoration. This technique has many advantages to sophisticated layering, facilitation stratification, anatomic construcrion and the stages of finishing and polishing. However, in some clinical situations, the unfolding of the steps to obtains this matrix can be time consuming or even infeasible. To facilitate the achievement of this apparatus, a technique was idealized allowing significant reducrion in clinical time. This matrix, called the "BRB Matrix" is widly discussed in a didactic and clinical manner in this article, presenting its advantages in clinical cases where it is imperative to use a guide for conduction a controlled layering. The simplicity of this approach, as well as reduced clinical time and finacial costs turn it feasible in an everyday clinical practice.

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)

Preparo e caracterização de compósitos polímero/cerâmica com potencial aplicação como sensor multifuncional

Pós-graduação em Química - IQ