Effects of different ceramic primers and surface treatments on the shear bond strength of restorative composite resin to zirconium.

Background and aims: Data are limited about the effect of ceramic primers on the bond of zirconia to restorative resin composite. The aim of this study was to assess the effect of different surface treatments and two ceramic primers on shear bond strength (SBS) of zirconia to restorative resin composite.

Materials and methods: 100 samples of zirconium ceramic blocks were randomly divided into 5 groups (n = 20) and received the following surface treatments: a)Control groupb)AL2 O3 abrasionc)Nd:YAG laserd)Er:YAG lasere)Bur preparation.Next, each group was divided into two subgroups of 20. In ten out of 20 specimens in each group, monobond plus and Tetric ceram composite resin were applied on the surface. ZPrime Plus and Elite composite were applied on the surfaces of the remaining 10 specimens in each group. Samples were then subjected to shear bond strength test in a universal testing machine until fracture. The mean SBS were calculated and statistically analyzed by two-way ANOVA and T-Test. P < 0.05 was considered statistically significant.

Results: In ZPrime plus subgroups, diamond bur yielded the highest bond strength. Laser groups showed no significant difference with the control group. In monobond plus subgroups, SBS of air abrasion and diamond bur subgroups was highest and Nd:YAG laser showed the lowest SBS. The lowest bond strength belonged to the Nd:YAG laser subgroup of monobond plus group.

Conclusions: Type of surface preparation significantly affected the bond strength.