Shear bond strength evaluation of five bonding agents in combination with three radiopaque composites on wet/dry dentine surfaces:: An in vitro study

Shear bond strength of five dentine bonding agents in combination with three radiopaque composites on dry and wet dentinal surfaces was evaluated in this study. Human premolar teeth mounted on acrylic resin were sectioned to expose dentinal surfaces onto which composites were fixed using a bonding agent. An observation of the shear strengths obtained from 36 composite/bonding agent combinations on dry/wet dentinal surfaces revealed no dentine adhesion for composites in the absence of a bonding agent. Adhesion using a bonding agent was found to enhance shear strength values to varying extents depending on the composite/bonding agent system used and the nature of the dentinal surface. Bond strengths were found to be higher on wet than dry dentinal surfaces though this was found to depend to a large extent upon the nature of the composite and/or bonding agent system used. In certain cases, combination systems other than recommended ones were found to provide better strength values. This study shows that shear bond strength depends not only on the nature of the dentinal surface but also is specific of the composite/bonding agent system used, thus providing an insight into their apparent clinical behaviour.