Factors affecting on the bond strength of dental zirconia to veneering porcelains

The bond strengths between two kinds of zirconia and three kinds of feldspathic veneering porcelains were measured. The specimens were prepared at four firing temperatures for three holding periods, respective opaque porcelain was painted and vacuum-fired. Then, each dentin porcelain was condensed in an acrylic resin mold and vacuum-fired under the conditions mentioned above. Cross sections of the interface between zirconia and porcelain were observed with a scanning electron microscope. The specimens were fixed to specimen holder on a universal testing machine. Data of the bonding test were statistically analyzed. The results showed that all the four factors statistically affected the bonding strength (p<0.01). The contribution of the firing temperature was highest and that of the porcelain type was lowest (p<0.01).