Avaliação da resistência ao microcisalhamento em cerâmicas vítreas reforçadas submetidas a diferentes tratamentos de superfície

Abstract

Zirconium-reinforced lithium silicate (ZLS) ceramics were developed with the purpose of creating ceramic materials with high mechanical and aesthetic performance. They do not have a defined surface treatment protocol. Thus, the objective of this study was to evaluate the effect of different types of surface treatments on the microcrystalline adhesive strength of ZLS ceramics and lithium disilicate ceramics cemented with a resin cement after thermocycling. The materials Celtra Duo, VITA Suprinity and IPS E.max CAD were used. Ceramic tablets with dimensions of 15x15x2 mm were made, which were submitted to 4 surface treatments: 10% hydrofluoric acid and silane; Blasting with 50μm aluminum oxide and silane; Blasting with Rocatec® 30μm and silane; and application of Monobond Etch & Prime. After the treatment, cylinders, 3mm in diameter, were made of resin cement on the ceramic surfaces. All samples were submitted to thermocycling. After aging, they were submitted to the micro-shear mechanical test. Additional analyzes were performed: Profilometry, Scanning Electron Microscopy and X-ray Dispersive Energy Spectrometry. Data were submitted to statistical analysis of variance (ANOVA) and Tukey's multiple comparison test. The surface treatment that presented the highest average adhesion strength, through the micro-shear test, was the conditioning with 10% Hydrofluoric Acid in all the ceramics analyzed. The blasting did not present a satisfactory adhesion resistance. It can be concluded that the resistance to micro-shear is influenced by each surface treatment employed and is dependent on each ceramic material.