[Preliminary study of bonding strength between diatomite-based dental ceramic and veneering porcelains].

PURPOSE: In order to choose the best veneering porcelain for diatomite-based dental ceramic substrate, the bonding strength between diatomite-based dental ceramics and veneering porcelains was measured, and the microstructure and elements distribution of interface were analyzed. METHODS: The coefficient of thermal expansion (CTE) of diatomite-based dental ceramics was detected by dilatometry. Three veneering porcelain materials were selected with the best CTE matching including alumina veneering porcelain (group A), titanium porcelain veneering porcelain (group B), and E-max veneering porcelain (group C). Shear bonding strength was detected. SEM and EDS were used to observe the interface microstructure and element distribution. Statistical analysis was performed using SPSS 17.0 software package. RESULTS: The CTE of diatomite-based dental ceramics at 25-500 degrees centigrade was 8.85×10-6K-1. The diatomite-based substrate ceramics combined best with group C. Shear bonding strength between group A and C and group B and C both showed significant differences(P<0.05). SEM and EDS showed that the interface of group C sintered tightly and elements permeated on both sides of the interface. CONCLUSIONS: The diatomite-based substrate ceramics combines better with E-max porcelain veneer.