Bond strength and interfacial characterization of eight low fusing porcelains to cp Ti

Objectives. The aim of this study was the interfacial characterization and the determination of bond strength of commercially available low fusing dental porcelain for Ti. Methods. Eight materials were included in this study: Duceratin, Duceratin Plus, Initial Ti, Ti-22, TiKrom, TitanKeramik, Triceram (powder) and Triceram (paste). Eight ISO 9693 bond characterization specimens from each porcelain were prepared according to manufacturers' instructions. One specimen from each group was embedded in acrylic resin and after metallographic preparation was studied under an SEM. Interfacial characterization was carried out with Backscattered Electron Imaging and X-ray EDS analysis operating in line scan mode. Metal-ceramic specimens were tested in three point bending at a crosshead speed of 1.5mm/min according to ISO 9693 requirements. Additionally the fracture mode (adhesive-cohesive) of all specimens was evaluated employing SEM/ EDS analysis. The results of bond strength and adhesive percentage were statistically analysed with one-way ANOVA and SNK multiple comparison test (a = 0.05). Additionally the possible correlation between the bond strength and fracture mode was also tested using Pearson test. Results. Interfacial characterization showed the mutual diffusion of Ti, Si, O and La along the Ti-ceramic interface. Only in Tricerap (paste) Zr showed an increased concentration at the interface. The results of bond strength classified the materials in the following decreasing order: TiKrom > Duceratin > Initial Ti > Duceratin Plus > Ti22 > Triceram(paste) > Triceram(powder) > TitanKeramik. No correlation (r = 0.132) between the fracture mode and bond strength of the selected material denoting that the fracture mode is irrelevant with the bond strength of Ti-ceramic joint and thus the former should not be applied for comparison among different materials. Significance. According to the results of this study the materials tested provided great difference in interfacial analysis and bond strength with metallic Ti. (C) 2009 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.