111 resultados para Ionospheric irregularities
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This is a clinical case report of a patient who presented with dental stains in the buccal and proximal aspects of the anterior teeth. Buccal stains were removed using the enamel microabrasion technique, and vital tooth bleaching with carbamide peroxide was also performed. Restorative procedures employing composite resin were done for a better result in the proximal aspect of teeth. Clinical significance: The authors observed the combination of these esthetic techniques improved the patient's smile. Today, dental esthetics attempts to imitate natural teeth by making them white, well-shaped, and aligned with no spots. This has enabled the development of several esthetic techniques, such as microabrasion to remove dental enamel surface stains and surface irregularities,1-6 and vital tooth bleaching to treat yellowish teeth.7 The enamel microabrasion technique uses different abrasive agents associated with chemical solutions,1,2,4,6 allowing the removal of intrinsic, hard-texture stains, and different coloring spots on the enamel surface, as well as correction of irregularities on the dental buccal surface.1,8 The various microabrasive products include the Opalustre® (Ultradent Products, http://www.ultradent.com)or Prema® Compound (Premier Dental Products, http://www.premusa.com), a low-concentration hydrochloric acid product associated with silica microparticles that is certainly effective for microabrasion technique,4,6,9,10 providing a good safety profile for the patient and professional. The microabrasion technique also promotes micro-reduction on the adamantine surface.4,5,10 In some cases, after its completion, microabrasion may cause teeth to become darker or yellowish because of the thinner remaining enamel surface, leading to more evident observation of the dentinal tissue, which in general determines tooth color. In these clinical conditions, correction of the color pattern of dental elements can be obtained with carbamide peroxide products applied in custom trays, such as the bleaching products Whiteness Perfect at 10% or 16% (FGM Productos Odontologicos, http://www.fgm.ind.br) or Opalescence® at 10% or 15% (Ultradent Products), with a considerable margin of clinical success, provided it is well indicated, well performed, and supervised by the professional.4,6,9,10 Considering all the aforementioned aspects, the authors present a clinical case about a dental-enamel microabrasion technique used to remove buccal enamel surface stains associated with dental vital bleaching and restorative procedures in the proximal aspect of anterior teeth. - See more at: https://www.dentalaegis.com/cced/2010/08/different-esthetic-techniques-used-in-combination-to-recover-the-smile#sthash.McFoH7El.dpuf
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Enamel microabrasion can eliminate enamel irregularities and discoloration defects, improving the appearance of teeth. This article presents the latest treatment protocol of enamel microabrasion to remove stains on the enamel surface. It has been verified that teeth submitted to microabrasion acquire a yellowish color because of the thinness of the remaining enamel, revealing the color of dentinal tissue to a greater degree. In these clinical conditions, correction of the color pattern of these teeth can be obtained with a considerable margin of clinical success using products containing carbamide peroxide in custom trays. Thus, patients can benefit from combined enamel microabrasion/tooth bleaching therapy, which yields attractive cosmetic results. Esthetics plays an important role in contemporary dentistry, especially because the media emphasizes beauty and health. Currently, in many countries, a smile is considered beautiful if it imitates a natural appearance, with clear, well-aligned teeth and defined anatomical shapes.1-3 Enamel microabrasion is one technique that can be used to correct discolored enamel. This technique has been elucidated and strongly advocated by Croll and Cavanaugh since 1986,4 and by other investigators1,2,5-13 who suggested mechanical removal of enamel stains using acidic substances in conjunction with abrasive agents. Enamel microabrasion is indicated to remove intrinsic stains of any color and of hard texture, and is contraindicated for extrinsic stains, dentinal stains, for patients with deficient labial seals, and in cases where there is no possibility to place a rubber dam adequately during the microabrasion procedure.1,2 It should be emphasized that enamel microabrasion causes a microreduction on the enamel surface,3,6,10 and, in some cases, teeth submitted to microabrasion may appear a darker or yellowish color because the thin remaining enamel surface can reveal some of the dentinal tissue color. In these situations, according to Haywood and Heymann in 1989,14 correction of the color pattern of teeth can be obtained through the use of whitening products containing carbamide peroxide in custom trays. A considerable margin of clinical success has been shown when diligence to at-home protocols is achieved by the patient and supervised by the professional.3 Considering these possibilities, this article presents the microabrasion technique for removal of stains on dental enamel, followed by tooth bleaching with carbamide peroxide and composite resin restoration, if required.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Pós-graduação em Engenharia Mecânica - FEG
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This work approaches the analysis of industrial refrigeration systems applied to a chemical processing industry that, in this case, consists of refrigeration machines, cooling tower system, cold water system and brine system. In this study it is highlighted the function and characteristics of different systems, including the main components, the most important features, their functionality and best practices. The motivation for this work is the fact that refrigeration systems are essential in many industrial processes, presenting a high energy consumption that is related to a significant parcel of production costs. It has aimed to understand the case studied in order to evaluate the energy efficiency of systems and to compare with Carnot efficiency and best available technologies. The assessment aims to identify irregularities, find opportunities and propose solutions that increases the performance of equipment and the overall system efficiency. Therefore, the studies intend to reduce the operation costs and generate gains for the company
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Pós-graduação em Matematica Aplicada e Computacional - FCT