الفهرس | Only 14 pages are availabe for public view |
Abstract The present study was conducted to evaluate the shear bond strength of two types of self-etching resin cements to zirconia ceramic after receiving different surface treatments, and to compare the mode of failure of the fractured surfaces. Eighty square shaped zirconia specimens (1cm x1cm x 3mm) were embedded in eighty acrylic molds. The eighty zirconia specimens with its acrylic molds were randomly divided into two groups of forty specimens each, according to the type of resin cement used: Group I: RelyX Unicem resin cement. Group II: Multilink Automix resin cement. Each group was further subdivided into four subgroups, ten specimens each, according to the type of surface treatment used: Subgroup A: Sandblasting with aluminum oxide particles. Subgroup B: Etching with hydrofluoric acid. Subgroup C: Treatment with Metal/Zirconia Primer. Subgroup D: No surface treatment. 1- Shear bond strength test Each specimen with its resin cement was mounted in a jig of universal testing machine. The shear load was applied at a constant cross-head speed of 1 mm/min with a parallel knife-edge blade touching the ceramic-cement interface until bonding failure. The shear bond strength was calculated in MPa. 2- Failure mode analysis The fractured cement on the surface of the zirconia specimens was examined using an optical stereomicroscope to determine the mode of failure. Each specimen assigned in Adhesive Remnant Index (ARI) value: 0: No cement left on the ceramic. 1: Less than half of the cement left on the ceramic. 2: More than half of the cement left on the ceramic. 3: All the cement left on the ceramic. |