Physico-chemical approach to pit and fissure sealant infiltration and spreading mechanisms.

PURPOSE

The purpose of this study was to investigate if hydrophilicity influences the depth of penetration and the microleakage and to determine if the state of enamel, wet or dry, influences the wettability and sealing capacity of sealants.

METHODS

HeliosealF, a hydrophobic sealant, and Embrace, a hydrophilic sealant, were tested. Sections were delimited on each of the polished enamel surfaces of 15 human molars to study the spreading of the selected sealants on wet or dry enamel; 40 molars were used to investigate the depth of penetration and microleakage on both dry and wet enamel. The surface-free energies were determined.

RESULTS

The spreading of Embrace was significantly better (P<.01) than that of HeliosealF, but there was no difference between the results obtained on wet or dry enamel (P=.90). While there was no difference in penetration between the 2 sealants (P=.95), their penetration was significantly lower on wet enamel (P=.01).

CONCLUSIONS

Sealant penetration and sealing characteristics are better when sealants are applied on dry enamel. Hydrophilicity and wettability did not have a direct influence on penetration or microleakage. A set sealant with a low surface-free energy could be an advantage in reducing bacterial adhesion.