Improvement in Ti-porcelain bonding by SiO₂ modification of titanium surface through cast method

Abstract

This study aimed to improve Ti-porcelain bonding strength through SiO₂ modifications. Wax patterns were coated with SiO₂ mixed with tetraethoxy silane (group C), patterns without coating were used as controls and subdivided into sandblasting group (group S) and polishing group (group P). Castingsurfaces were analyzed with XRD, while Ti-ceramic interfaces were characterized using SEM/EDS. Metal-ceramic specimens were tested in three point bending, and characterizations were also analyzed with SEM/EDS of porcelain debonding surfaces. In group C, SiO₂ and Ti₅Si₃ phases were observed; SEM micrograph showed that Ti-porcelain had a compacted interface, and EDS maps of the interface illustrated the diffusion of Si, Al, and Sn to Ti, and cohesive fracture within the bonding agent. The bond strength of group C was 39.04±5.0 MPa, which was 15% higher than that of group S and 32% higher than that of group P. SiO₂ coating could improve Ti-porcelain bond strength.