Penetration of Filled and Unfilled Resin Sealants on Different Enamel Substrates.

Purpose: To evaluate the penetration ratio of filled and unfilled resin-based sealants on different enamel substrates and pit and fissure morphologies.

Methods: Forty-eight occlusal enamel blocks obtained from impacted human third molars were randomly divided (n equals eight) according to enamel substrates (sound; caries-like lesion; caries-like lesion plus topical fluoride application) and sealant material (FluroShield; Helioseal Clear Chroma). Sealants were applied on the enamel surface. The specimens were stored in 100 percent humidity for 24 hours at 37 degrees Celsius, sectioned in a buccal-lingual direction (at approximately 50 μm), and examined to determine the sealant penetration ratio (b x 100/a; a equals total fissure length and b equals sealant penetration length) and pit and fissure morphology (V-, U-, or Y-shaped). Statistical analysis was performed using Friedman and Kruskal-Wallis tests (P<0.05).

Results: Enamel substrate and sealant material did not affect the sealant penetration ratio, with no interactions between these factors. Moreover, the morphology significantly affected the sealant penetration, with the "Y"-shaped fissures presenting the lowest sealant penetration ratio compared to "U-"shaped (P=0.0001) and "V-" shaped fissures (P=0.0018).

Conclusions: Pit and fissure morphology was a critical factor on sealant's penetration capacity; however, enamel substrate and sealant type did not affect sealant's penetration ratio.