Shear bond strength of Composite / Amalgam restorations: Effect of using, adhesive cement

ABSTRACT

The aim of this study was to evaluate the shear bond strength [SBS] of composite/amalgam restorations when adhesive resin cement was used. 60 Acrylic cylinders were prepared using special Teflon molds. A square-shaped cavity was made at the center of each cylinder. The samples were divided into four groups [n = 15]. After amalgam condensation and burnishing in the first group, a two parts Teflon die with a cylindrical hole at the center was placed on the amalgam surface. These holes were filled with composite-resin. Single bond and Rely X-ARC were applied on amalgam surfaces respectively, prior to curing the composite-resins in the second group. In groups 3 and 4, the prepared amalgam samples were kept in 37 C for 24 hours. Then they were identically roughened using burs. In group 3, composite was bonded immediately and in group 4, first single bond, and then Rely-X ARC were applied before curing the composite. The SBS was determined by DARTEC testing machine. The mean SBS for the study groups were 9 +/- 2.77, 8.74 +/- 6.42, 6.13 +/- 2.35 and 8.25 +/- 1.43 respectively. The maximum value was related to group 1 and the minimum value belonged to group 3. However, there were no significant differences between the study groups. Application of Rely X-ARC in amalgam/composite interface did not cause any significant difference