Sérgio Roberto Costa Vieira

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The purpose of this study was to evaluate the shear bond strength of resin-modified glass ionomer cement in a saliva-contaminated environment, using different enamel pretreatments. A total of 125 freshly extracted, bovine permanent inferior incisors were divided into five groups. Group I received 10% polyacrylic acid, moistened with saliva/Fuji Ortho LC(More)
OBJECTIVES Colour changes of the luting material can become clinically visible affecting the aesthetic appearance of thin ceramic laminates. The aim of this in vitro study was to evaluate the colour stability and opacity of light- and dual-cured resin cements and flowable composites after accelerated ageing. METHODS The luting agents were bonded (0.2 mm(More)
The aim of this study was to determine the pH of several commercially available in-office and at-home dental bleaching products stored at room temperature and refrigerated. The products were divided into in-office (n=09) and at-home (n=12) bleaching gels and submitted to two different temperatures, namely, room temperature (23 degrees C +/- 1 degree C) and(More)
This study quantitatively evaluated the fluorescence intensity of resin composites with different opacities and translucencies and determined changes in fluorescence after accelerated aging, using human enamel and dentin as controls. Six microhybrid and nanofilled composites, each in three different shades, were tested. Ten sound human incisors were used to(More)
This paper presents a comparative study of three different methods for usability evaluation in Web mobile application: Heuristic Evaluation, Cognitive Walkthrough, and Web Design Perspectives-based Usability Evaluation (WDP). This research aims to evaluate which method presents the best performance on the usability evaluation of web applications for mobile(More)
This in vitro study evaluated the Knoop hardness of the composite resins Charisma (C) and Durafill VS (D) polymerized in 3 different conditions: at room temperature (A) (23 +/- 1 degrees C); refrigerated at 4 +/- 1 degrees C and immediately photo-activated after removal from the refrigerator (0); and, refrigerated at 4 +/- 1 degrees C and photo-activated(More)
The aim of this study was to evaluate, in vitro, frictional forces produced by ceramic brackets and arch wires of different alloys. Frictional tests were performed on three ceramic brackets: monocrystalline (Inspire ICE), polycrystalline (InVu), polycrystalline with metal slot (Clarity), and one stainless steel bracket (Dyna-Lock). Thirty brackets of each(More)
AIM The objective of this study was to evaluate the effect of light polymerization on water sorption and solubility of hybrid composites. METHODS AND MATERIALS Three composite resins were used to make discs cured with either quartz-tungsten halogen (QTH) or light emitting diode (LED) curing units. The specimens were stored in a desiccator at 37 degrees C(More)
OBJECTIVE The aim of this study was to establish the reaction kinetics of 35% hydrogen peroxide and sodium ascorbate and to determine the mass of antioxidant required to neutralize the bleaching gel. METHODS The method used to quantify sodium ascorbate was based on the United States Pharmacopeia (1995)(26). Oxidation-reduction titration was used to(More)