Sports dentistry: a perspective for the future

Sports Dentistry (SD) acts in the prevention, maintenance and treatment of oral and facial injuries, as well as the collection and dissemination of information on dental trauma, beyond stimulus to research. Establishes as a duty for the dentist detect problems related to the athlete’s stomatognathic system. This essay is based on the provided data from the literature related to SD, including definition, practice areas and research fields. To discuss the data, six areas were categorized: shares in sports dentistry; oral health of athlete; sports-related dental implications; dental-facial trauma; face shields; and mouthguards. The analyzed data show that the SD is still an underexplored field of action by dentists, but it is expanding, despite not being recognized specialty by the Federal Council of Dentistry, but the Brazilian Academy of Sports Dentistry has been created with a mission to show the real importance of Dentistry in sport. The dentist should be part of the group of professionals associated with the athlete to perform periodic checks in order to ensure oral health which may contribute to athletes´performance. When impact occurs, however, it would be possible reduce the severity of the impact related to injuries, by using helmets, masks, goggles, face shields and mouthguard. Additionally, it is imperative that dentists, sports coaching, athletes, and professional who work with athletes be aware of the benefits of incorporating SD as an important academic and professional subject

Weed community composition in different agro-systems

Weed communities in agricultural systems are diverse and subjected to different agronomic practices. In this study, a phytosociological survey of the weed community in different cropping systems consisting of corn, horticulture, perennial cultivation of Jatropha curcas and pasture of Urochloa brizantha in Rio Verde, GO, Brazil, was carried out. Assessments were performed at the beginning (October 2011) and at the end (March 2012) of the rainy season. After identifying and counting species, were calculated the phytosociological indices of density, frequency, abundance and relative importance, as well as the diversity index of Shannon-Wiener, evenness index of Pielou and similarity coefficient of Sorense. Were found 46 species of sixteen families, especially Poaceae. The most important species were: Alternanthera tenella in the annual growth environment during the both periods; Panicum maximum (early rainy season) and Chamaescy hirta (end of the rainy season) in the vegetable garden; Eleusine indica (early rainy season) and Galinsoga parviflora (end of the rainy season) in the perennial crop and Sida rhombifolia (early rainy season) and Neonotonia wigrtii (end of the rainy season) in the pasture. Lower diversity indices and evenness were observed in the pasture environment. Sampling time presented a higher impact on similarities when compared to the different environments.Weed communities in agricultural systems are diverse and subjected to different agronomic practices. In this study, a phytosociological survey of the weed community in different cropping systems consisting of corn, horticulture, perennial cultivation of Jatropha curcas and pasture of Urochloa brizantha in Rio Verde, GO, Brazil, was carried out. Assessments were performed at the beginning (October 2011) and at the end (March 2012) of the rainy season. After identifying and counting species, were calculated the phytosociological indices of density, frequency, abundance and relative importance, as well as the diversity index of Shannon-Wiener, evenness index of Pielou and similarity coefficient of Sorense. Were found 46 species of sixteen families, especially Poaceae. The most important species were: Alternanthera tenella in the annual growth environment during the both periods; Panicum maximum (early rainy season) and Chamaescy hirta (end of the rainy season) in the vegetable garden; Eleusine indica (early rainy season) and Galinsoga parviflora (end of the rainy season) in the perennial crop and Sida rhombifolia (early rainy season) and Neonotonia wigrtii (end of the rainy season) in the pasture. Lower diversity indices and evenness were observed in the pasture environment. Sampling time presented a higher impact on similarities when compared to the different environments

Fiber Post Etching with Hydrogen Peroxide: Effect of Concentration and Application Time

AbstractIntroductionEtching is necessary to expose the fibers and enable both mechanical and chemical bonding of the resin core to the fiber post. This study evaluated the effect of concentration and application time of hydrogen peroxide on the surface topography and bond strength of glass fiber posts to resin cores.MethodsFiber posts were etched with 24% or 50% hydrogen peroxide for 1, 5, or 10 min (n = 10). Posts without any treatment were used as a control. After etching, the posts were silanated and adhesive resin was applied. The posts were positioned into a mold to allow a self-cured resin core to be inserted. The post/resin assembly was serially sectioned into five beams that were subjected to a tensile bond strength test. Data were subjected to two-way ANOVA and Tukey test (α = 0.05). The surface topography was analyzed using scanning electronic microscopy.ResultsNon-etched post presents a relatively smooth surface without fiber exposure. Application of hydrogen peroxide increased the surface roughness and exposed the fibers. All experimental conditions yielded similar bond strength values that were higher than those obtained in the control group.ConclusionBoth 24% and 50% hydrogen peroxide exposure increased the bond strength of resin to the posts, irrespective of the application time

Estimativa do IAF de cafeeiro a partir do volume de folhas e arquitetura da planta

The methods used for estimating the leaf area index (LAI) of coffee (Coffea arabica L.) show limitations related to therepresentation of some aspects of coffee crops, affecting the LAI in time and space. This work was developed to propose a method forassessing the LAI of coffee aiming to reduce those limitations. We studied plants in the production phase of the Mundo Novo and Catuaívarieties, in plantations located in Lavras-MG, during the dry season and rainy season from 2010 to 2011. The height, total length ofprimary branches, the length of the region without leaves in the canopy and the LAI of those plants were evaluated. These data wereused to estimate the volume occupied by leaves and, subsequently, to obtain equations that describe the behavior of LAI in relation tothis volume. There were three equations that described the LAI variations in relation to the volume occupied by leaves: linear,expolinear and seasonal. These three models showed realistic estimates when applied to plants from plantations located in TrêsPontas-MG. Potentially, this method can be applied for estimating the LAI of a plant or canopies. It has the advantage of a morerealistic representation of the shape of the plant in time and space compared to similar methods. With the proposed method is expectedto meet the demands of productivity forecasting models for coffee, reducing the limitations observed in the commonly used methods forLAI determination.Os métodos de estimativa do índice de área foliar (IAF) utilizados para cafeeiros (Coffea arabica L.) apresentamlimitações relacionadas à representação de particularidades da cultura que afetam o IAF no tempo e no espaço. Desenvolveuseeste trabalho objetivando propor um método de estimativa do IAF de forma a reduzir essas limitações. Foram utilizadoscafeeiros em fase produtiva, de cultivos da região de Lavras-MG, das variedades Mundo Novo e Catuaí, coletados durantea estação seca e a estação chuvosa de 2010 a 2011. Nessas plantas avaliou-se a altura a partir do nível do solo, comprimentototal de ramos plagiotrópicos, o comprimento da região sem folhas na copa e o IAF. Esses dados foram utilizados paraestimar o volume de folhas das plantas e, posteriormente, para a obtenção de equações que descrevem o comportamento doIAF em função do volume de folhas. Verificaram-se três ajustes das variações de IAF em função do volume de folhas:comportamento linear, expolinear e sazonal. Os três modelos apresentaram estimativas realistas, quando aplicados emcafeeiros do município de Três Pontas-MG. Potencialmente, os modelos podem ser aplicados na estimativa do IAF de umaplanta isolada ou para parcelas homogêneas. Possuem a vantagem de uma representação mais realista da forma da planta notempo e no espaço em comparação com métodos semelhantes. Com o método proposto, espera-se atender demandas demodelos de previsão de produtividade de cafeeiros, reduzindo as limitações observadas nos métodos comumente utilizadospara a determinação do IAF