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 thre e radiopaque composites on dry and wet dentinal surfaces was evaluated in t his study. Human premolar teeth mounted on acrylic resin were sectioned to expose dentinal surfaces onto which composites were fixed using a bonding a gent. An observation of the shear strengths obtained from 36 composite/bond ing agent combinations on dry/wet dentinal surfaces revealed no dentine adh esion for composites in the absence of a bonding agent. Adhesion using a bo nding agent was found to enhance shear strength values to varying extents d epending on the composite/bonding agent system used and the nature of the d entinal surface. Bond strengths were found to be higher on wet than dry den tinal surfaces though this was found to depend to a large extent upon the n ature of the composite and/or bonding agent system used. In certain cases, combination systems other than recommended ones were found to provide bette r strength values. This study shows that shear bond strength depends not on ly on the nature of the dentinal surface but also is specific of the compos ite/bonding agent system used, thus providing an insight into their apparen t clinical behaviour.