Some surface conditions of polymers used to manufacture provisional prosthesis, such as roughness and surface energy, may alter in the esthetical outcome of these restorations, by favouring adherence of microorganisms. Therefore, this study aims to investigate the adhesion of Streptococcus sanguinis on the surface of polymers used to manufacture provisional prosthesis, treated or not with a glaze polishing material, submitted to a thermocycling procedure. Different temporary polymers will be tested, heat-cured acrylic resin (HC) and light-cured acrylic resin (LC), and composite resins of Bis-ACRYL and BiS-GMA. It will be made 36 specimens for each resin, in which half of these will be mechanic polished and half polished with the light cured glaze. Then these samples will be randomly divided into 4 groups (n = 9), half to be used for the baseline period and half to be used after the thermocycling. For the thermocycling process the samples will be immersed in distilled water and be subjected to alternating 30 seconds baths at the temperatures of 5 ± 1 ° C and 55 ± 1 ° C, in a total of 2000 cycles. All samples will be subjected to surface energy and roughness tests and microbiological analysis. A triple microbiological analysis will be performed in three independent experiments, in which the colony count will be verified by the number of CFU / mL. The data obtained from surface energy, roughness and microbiological analysis will be submitted to appropriate statistical tests in order to compare the mean values and, when possible, correlate the data for the different methods, completing the analysis.
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