Effect of temporary cements on the bond strength of ceramic luted to dentin

The purpose of this study was to evaluate the effect of either eugenol-containing or eugenol-free temporary cement removal by excavator or sandblasting on the shear bond strength of ceramic luted to dentin. A self-etching primer system, Panavia F 2.0, Kuraray Medical (PF2), and a total-etch bonding system, Excite/Variolink II, Vivadent (EXV), were used. One hundred and forty human molars, ground to expose dentin surfaces, were divided into 14 groups (seven groups for each adhesive system). For each adhesive system, either a eugenol-containing (Temp bond) or a eugenol-free (Temp bond NE) temporary cement was applied to the dentin surface for 7 days, then removed by an excavator or sandblasting (four groups). Three control groups were studied where fresh dentin was either scratched by excavator or sandblasted, or underwent no surface treatment. After application of the adhesives, ceramic cones (Cerafil inserts) were adhesively luted to standardized dentin areas. After 24 h storage in distilled water, the shear bond strengths were determined at a cross-head speed of 0.75 mm/min. For each adhesive system, neither the method of temporary cement removal nor the type of temporary cement affected the bond strength significantly ( P≤0.05). EXV showed statistically higher bond strengths (26.6–31.6 MPa) than PF2 (8.6–12.9 MPa) within all groups. The use of temporary cements, either containing eugenol or not, does not alter the retentive strength of ceramic restorations luted to dentin using the tested adhesive systems, whether the temporary cements are removed by excavator or sandblasting.