The effect of different adhesive strategies and diamond burs on dentin bond strength of universal resin cements.

OBJECTIVES

To evaluate the shear bond strength (SBS) of universal cements (UCs) to dentin prepared with different diamond burs using various adhesive strategies.

MATERIALS AND METHODS

One-hundred-twenty molars were prepared to expose the mid-coronal dentin. The teeth were divided into two groups according to diamond bur preparations: coarse and super-fine grit burs. The specimens were bonded to lithium disilicate discs using two UCs (RelyX Universal, RXU and Panavia SA Luting Multi, PSA) with different adhesive strategies (self-adhesive, SA; self-etch, SE and etch-and-rinse, ER). SBS was measured using a universal testing machine. The cement-dentin interfaces were observed using scanning electron microscopy.

RESULTS

Dentin SBS was significantly influenced by the adhesive strategies and the type of UCs (p < 0.05) but not for the different diamond bur preparations (p > 0.05). UCs used with ER had significantly higher SBS values than UCs used in SA mode (P < 0.05), except for PSA with super-fine diamond bur. RXU in SE mode exhibited significantly higher SBS than SA mode (P < 0.05). Regarding UCs, RXU showed a higher SBS than PSA, particularly in the SE modes when the dentin was prepared with a coarse diamond bur (P < 0.05).

CONCLUSION

The use of UCs combined with universal adhesives exhibited higher dentin bonding performance compared with the use of UCs alone.

CLINICAL SIGNIFICANCE

The etch-and-rinse mode combined with a universal adhesive is recommended to achieve the highest dentin bond strength of universal cements.