Shear Bond Strength of Self-Adhesive Resin Cements to Dentin

Objective:The aim of this study was to assess the bonding performance of two new self-adhesive resin cements and one conventional resin cement when used for the luting of indirect composite restorations using a shear bond strength test set-up.

Methods: Thirty buccal dentin specimens were prepared from human molar teeth and divided into three groups (n=10). Thirty light polymerized nanohybrid composite resin discs of 4x2 mm (Premise, Kerr) were prepared to simulate laboratory processed composite resin restorations. In group I composite discs cemented to dentin using conventional resin-based cement with its proprietary adhesive system as a control (Variolink II, Vivadent).In group II and III two self adhesive resin cements RelyX Unicem (3M ESPE) and G Cem (GC) were used for cementing respectively. After storage in distilled water the shear bond strength test was done.The data were subjected to ANOVA and Bonferroni paired comparisons.

Results: Statistically significant differences were found betwen the bond strength values of cement systems (p<0.05).The shear bond strength values were 11.6±2.2 MPa, 8.77±2.3MPa and 6±2 MPa for G-Cem,RelyX Unicem and Variolink II respectively.

Conclusion: For the cementation of indirect composite restorations the use of a simplified application procedure does not decrease bonding effectiveness to dentin as statistically higher values were determined with self adhesive resin cements.