Aim of the study was to compare the trimming and non-trimming variants of the microtensile technique with the 'micro' push-out test in the ability to measure accurately the bond strength of fiber posts luted inside root canals. In 15 endodontically treated teeth (Group A), fiber posts were cemented with Excite DSC in combination with Variolink II (Ivoclar-Vivadent). In 15 roots RelyX Unicem (3M-ESPE) was used for fiber post luting (Group B). Within each group, the bond strength of cemented fiber posts was assessed with the trimming and non-trimming microtensile technique, as well as with the push-out test. The great number of premature failures (16.9% in Group A, 27.5% in Group B) and the finding of high standard deviation values make questionable the reliability of the trimming microtensile technique. With the non-trimming microtensile technique, only five sticks were obtained from a total of six roots. The remaining specimens failed prematurely during the cutting phase. With the push-out test no premature failure occurred, the variability of the data distribution was acceptable, and regional differences in bond strength among root levels could be assessed. Relatively low values of bond strength were, in general, recorded for luted fiber posts. In conclusion, when measuring the bond strength of luted fiber posts, the push-out test appears to be more dependable than the microtensile technique.

As intervenções do grafite e da pichação na cidade criam fissuras no real que, por vezes, geram reações violentas, já que a maioria de nós tem dificuldade em lidar com fenômenos atuantes fora da dita ordem natural das coisas. Seres fantásticos e uma tipografia hermética desafiam não só o senso comum, mas também as leis. "Ficções urbanas" pretende analisar as diferenças entre as estratégias da pichação e do grafite na cidade de São Paulo. Esses procedimentos são considerados em suas dinâmicas de apropriação do espaço cotidiano e em relação ao quadro teórico do debate artístico contemporâneo.
Interventions on urban space such as graffiti and "pichação" create cracks in the real that sometimes may generate violent reactions, since most of us find difficulties in dealing with phenomena that stretch out our sense of security. Fantastic creatures and a typography that is hard to read defy not only common sense, but also the laws. The text "Urban fiction" analyzes the differences between the strategies of graffiti and "pichação" in São Paulo. These procedures are considered in their dynamics to take over urban landscape and examined in relation to the theoretical framework of contemporary art debate

O objetivo desse estudo foi investigar o efeito do armazenamento de 4 sistemas adesivos de frasco único por 1 ano sobre a resistência de união à dentina, através do teste de microtração. O esmalte oclusal de 16 molares humanos foi removido expondo superfície dentinária. Uma camada de “smear” padrão foi criada pela abrasão em lixas de granulação decrescente. Os dentes foram divididos em quatro grupos: [EX] – Excite (Ivoclar-Vivadent); [SB] - Single Bond (3M-ESPE); [OS] - Optibond Solo Plus (Kerr Corporation) , [PB] - Prime & Bond NT (Dentsply-DeTrey). Blocos de resina com 5 mm de altura foram construídos nas superfícies dentinárias tratadas com os adesivos. Após 24 horas de armazenamento, os corpos foram seccionados para obter uma série de “palitos” com área de 0,8 mm_ . O teste de microtração foi realizado para cada “palito” em uma máquina de testes universal a 0,5mm/min. Os adesivos foram armazenados, por 1 ano, em estufa a 33ºC, sendo abertos uma vez por dia e pressionados expondo 1 gota. Após esse período, todos os procedimentos para o teste de microtração foram repetidos para outros 16 molares. Os dados foram analisados utilizando os testes de Análise de Variância de 2 fatores e Tukey. Os valores médios obtidos (imediato/1 ano) em MPa foram: [EX] 40,1ª / 39,4a; [SB] 42,8a / 46,7a; [OS] 35,3a / 39,4a; [PB] 22,5b / 0,0c. Conclusões: Os resultados imediatos mostraram valores de resistência inferiores para o adesivo Prime & Bond NT, que sofreu influência significativa do tempo de armazenados por 1 ano.

The aim of this in vitro study was to analyze the wear rate of three direct restorative materials (Dispersalloy,Z250 and Surefil) using two methods of evaluation: visual M-L scale and profilometry. The occlusal surfaces of twelve human molars were ground flat using diamond disc. Standardized cavities were prepared using nº 721PM diamond bur and restored according to the manufacturers’ instructions. They were then stored in distilled water at 37ºC for 24 hours, polished, replicated and mechanical cycled. Wear assessment was performed using the ML scale and profilometry. Different values were observed for the tested materials depending on the method of evaluation. For the M-L scale no difference was found among Dispersalloy, Surefil and Z250, whereas the profilometer showed that Dispersalloy had lower wear than Surefil and Z250 (p<0.01). The M-L scale demonstrated poor accuracy when compared to the profilometer method (p<0.05) to evaluate the wear rate of restorative materials.

No abstract

This study evaluated the compression strength of gypsum type IV and V according to 2 variables: 1) water proportioned randomly or as recommended by the manufacturer and 2) according to 3 (three) different groups of operators (dentists, technicians and dental students). 180 specimens, produced according to ADA regulation nr. 25 underwent, after seven days (dry resistance), the compression strength test in an universal testing machine. After statistical analyses of the data, there was no statistical significant difference regarding the group of operators. Regarding the variable proportion, the specimens manufactured using a random proportion of water/gypsum powder presented a lower compression value (626,2 Kgf/cm2) when compared to the group where the amount of water/gypsum powder followed the recommendation of the manufacturer (741,7 Kgf/cm2). This difference was statistically significant (p<0.01).

Branch-and-Bound techniques have been successfully used to solve combinatorial optimization problems. One common approach to improve the effectiveness of these techniques is via parallelization. The parallelization of Branch-and-Bound computations, however, is not trivial and programmers may experiente difficulties both in terms of correctness and efficiency of the parallelized applications. In this paper we present an environment that helps programmers in developing efficient parallel Branch-and-bound applications. This environment integrates two tools: (1) Sabor, which aids in designing those applications, and (2) Carnival, which is a performance measurement and analysis tool that helps the programmer in understanding the performance of those applications. We also present the Carnival user interface and illustrate its usefulness and functionality by identifying and explaining sources of overhead in example applications.