[ in vitro evaluation on shear bond strength of three resin luting cement systems in bonding of base metal alloy and ceramco and inceram porcelains to dentin]

ABSTRACT

Developed synthetic resin cement are recommended for cementation of crown and bridges. Bonding of adhensive resins to ceramic, metal, enamel and dentin is an important factor for a successful clinical restoration. The purpose of this study was to determine the shear bond strength of 3 luting cement systems [Dual cure, self Cure and resin modified glass inomer] for bonding the base metal alloy, Ceramco and Inceram porcelain to dentin. In this experimental study, 90 extracted human teeth were prepared and buried in self cure acrylic resin while the buccal surface remained out of the acrylic material. The enamel of the buccal surface were removed and a flat surface was obtained on the dentin. Thirty blocks of base metal alloy, Ceramco laminate porcelain and Inceram were prepared with the dimensions of 6x4x2mm, and divided into 3 subgroups. Each subgroup was cemented with C and B Metabond, Panavia F and Rely X to dentin. After that, they were thermocycled between 5°C to 50°C for 500 cycles, the shear bond strengths were measured in an universal testing machine. Finally, the specimens were inspected under a stereomicroscope with a magnification of 40 to determine the modes of failure. The data were analysed using SPSS software [2-way ANOVA, Duncan's test and Fisher's Exact test]. Maximum shear bond strength in bonding of 3 experimental plates to dentin with 3 adhesive resin systems are as follows Panavia F for base metal plates [15.316 +/- 2.925 MPa], C and B Metabond for Ceramco porcelains [11.789 +/- 1.730 MPa] and Inceram porcelains [10.512 +/- 3.249 MPa]. Within the limitation of this study, the best cement for cementation of base metal plates was Panavia F or C and B Metabond cement. Among these three evaluated cements,C and B Metabond cement proved to be better for cementation of Ceramco porcelains to dentin and C and B Metabond or Panavia F for cementation of Inceram plates to dentin