Avaliação dos parâmetros físicos e biomecânicos de materiais restauradores de uso direto e indireto

Abstract

The success and longevity of a ceramic restoration or composite resin are related to satisfactory marginal sealing, material integrity and aesthetics. Replacement of restorations as general practitioners in clinical manifestations such as fractures, color change and loss of gloss. Thus, it is important to evaluate possible factors related to failure of indirect and direct restorations in order to prevent retreatment. Thus, the objectives of this study were: Objective 1: to evaluate the effect of different finishing-polishing protocols on the mechanical properties and surface topography of pressable fluorapatite glass ceramic. Objective 2: to evaluate the effect of immediate and delay polishing on the mechanical properties of hardness, color stability and surface topography of three different types of composite resins after immersion in coffee. Objective 3: to evaluate the mechanical and physical properties of different bulk-fill polymerized with different light-curing units. The experimental methods used in the laboratory studies were profilometry and atomic force microscopy to characterize surface roughness, spectrophotometer associated with optical fiber to measure gloss, scanning electron microscopy for qualitative evaluation of surface topography, resistance to biaxial flexural strength to evaluate the flexural strength, spectrophotometer for color analysis, Fourier transform infrared spectrometer (FTIR) to evaluate the degree of conversion and indentation test to calculate Knoop microhardness. After statistical analysis, it can be concluded that the polishing protocol using systems with polishing tips of sequential abrasives can be a good alternative for chairside finishing of adjusted pressable fluorapatite glass ceramic surfaces. Polishing immediately or after 24 hours decreases the surface roughness and color change of different categories of composite resins, in addition causes the increase of hardness of the restoration. The bulk fill resin composites present mechanical behavior depending on the photopolymerizing source. The degree of conversion, microhardness and diametral tensile strength of different bulk fill resins are influenced by the photopolymerization units used in dental practice.