Shear bond strength and scanning electron microscopic observation of current dentinal adhesives

The purpose of this investigation was to determine the shear bond strengths of three new dentinal adhesives and to compare them to the strengths of four adhesives tudied previously. With Superbond as the adhesive, fractures occurred cohesively in the composite resin or in the bonding material. Mirage Bond fractures occurred at the interface of the adhesive and the intermediate bonding material. XR-bonding system specimens fractured at the interface of the primer and the smear layer or at the interface of the primer and the bonding material. The bond strength of Superbond was significantly greater than that of XR-bond and Mirage Bond, and XR-bond had signficiantly greater strength than did Mirage Bond. When strength values for these adhesives were compared to those from a previous study, it was found that there was no statistically significant difference between Scotchbond 2 and Superbond, none between Tenure and XR-bond, and none between Mirage Bond, Gluma, and Dentin Adhesit.