Microleakage of five dentinal adhesives.

This study compared the microleakage characteristics of four dentinal adhesives against Scotchbond 2 as a control and discusses the results in light of recently reported bond strengths for these same materials. Dentin specimens from 100 caries-free extracted human molar teeth were used in a matched pair design. In each of the four test materials, 25 tooth sides were treated along with the matching control, subjected to 500 thermocycles (5 to 55 degrees C), followed by AGNO3 dye penetration, specimen sectioning, and evaluation by low-power stereomicroscopy. Mean microleakage values were as follows (microns): Scotchbond Multipurpose, 498.0; All-Bond 2, 530.8; Syntac, 748.0; X-R Bond, 844.9; and the Scotchbond 2 control (a composite score created by averaging four sets of 25 tooth sides), 1095.2. Paired t-tests showed that Scotchbond Multipurpose, Syntac, and All-Bond 2 had significantly lower microleakage than the control (P=0.0001); however, X-R Bond had no significant difference from the control (=0.4634).