Analysis of the connection of a nickel-chromium alloy with dental ceramics after aluminum oxide abrasive blasting

Abstract

Fixed prosthetic restorations in the form of ceramic crowns or bridges are characterized by good aesthetics and durability. The most important turn out to be the mechanical attachment of the ceramic material in the unevenness of the metal, formed after abrasive blasting. The aim of this research is to investigate the impact of abrasive blasting of a nickel-chromium alloy on the covering the unevenness with ceramics. In the research was used a Ni-Cr alloy (Heraenium® NA, Hera). The metal surface was blasted with alumina of variable size (50, 110 and 250 µm) and pressure (0.4 and 0.6 MPa), which was then fired with ceramics in the form of 2 layers of IPS Classic Opaque (Ivoclar Vivadent). Samples were hot mounting and cut to obtain a cross-section of the connection. The samples was examined under a Scanning Electron Microscope. The results show the presence of air bubbles at the metal-ceramic interface and in the layers of ceramic material. The photographs show a difference in the appearance of the unevenness of the metal surface by comparing samples after blasting with an abrasive of different sizes. No significant differences in the appearance of metal roughness are observed when comparing samples after treatment with the same grain size and different pressures.