A scanning electron microscopic and tensile bond strength evaluation of Gluma dentin bond application, as a function...

Scanning Electron Micrographs (SEM) and Tensile Bond Strength (TBS) measurements were used to evaluate the influence of three different dentinal pretreatments. A new testing device was developed for the TBS measurements. Human tooth roots were ground with a diamond bur. Tap water, Gluma Cleanser, and Neo-Sabenyl-Tubulicid were used to clean the surfaces before SEM inspection. The adhesion between root dentin and Lumifor Composite restorations was mediated by Gluma Bond. SEM observations revealed that a 30-second application of Gluma Cleanser removes the smear layer totally. Neo-Sabenyl-Tubulicid produced a very smooth surface. Application of Gluma Bond did not alter this appearance. Mean TBS values for surfaces sprayed with tap water, Gluma Cleanser, and Neo-Sabenyl-Tubulicid were 10 MPa, 7.3 MPa, and 10 MPa, respectively. There was a significant difference between group 2 (Gluma Cleanser) and the other groups. From this in vitro study, it is concluded that total removal of the smear layer with opening of the dentinal tubules (e.g., by means of Gluma Cleanser) reduces the TBS of Gluma Dentin Bond-Lumifor restorations to ground root dentin.