Sealing ability of dentin coating using adhesive resin systems

To assess the sealing ability of dentin coating using adhesive resin systems to verify its potential in protecting the dentin/pulp from the oral environmental stimuli.

15 extracted human premolars were prepared for complete crowns and the electrical resistance of their coronal dentin was measured. The prepared teeth were then randomly divided into three groups, and the prepared dentin surface of five teeth in each group was coated using one of three adhesive resin systems (All-Bond 2, Clearfil Liner Bond II, Super-Bond D-Liner) with low viscosity resins. Measurements for electrical resistance of the prepared coronal dentin was repeated after the first and second coat of the low viscosity resins, and at 1 and 4 weeks of storage in a physiological saline solution. Additionally, three prepared teeth were exposed to either cold (37 degrees C --> 4 degrees C) or heat (37 degrees C --> 60 degrees C) stimulus and the temperature change was monitored inside the pulp chamber. Time-temperature curve was obtained before and after the first and the second dentin coating.

Before dentin coating electrical resistance of the coronal dentin ranged from 1 to 11 k(omega), and increased significantly after the first coating by 3-15 times, and by 5-185 times after the second coating. Thermal diffusion was significantly smaller in the dentin after the coating. Before coating, the temperature change inside the pulp chamber ranged from 2-5 degrees C at 5 seconds after the thermal stimuli were applied. This decreased significantly to between 0.3-0.5 degrees C after the coating.