Method: A group of 32 healthy permanent posterior teeth were collected for the study. Fissures were minimally prepared. Teeth were randomnly divided into 4 groups (n=8). Group 1: Self-adhering flowable resin (Vertise Flow, Kerr), Group 2: Giomer pit-and-fissure sealant with primer (Beautiseal, Shofu), Group 3: Resinous sealant with etching gel (Teethmate F1 Opaque, Kuraray), Group 4: Resinous sealant with etching gel (Teethmate F1 Natural, Kuraray). Specimens were thermocycled (1500 cycles 5o C – 36o C – 55o C – 36o C with a dwell time of 15 seconds), covered with varnish and immersed for 24h in 5% aqueus methylene blue solution. Consecutively, specimens were sliced twice mesiodistally in a microtome and evaluated at 400X magnification. Microleakage was classified according to the depth of dye penetration. The highest score was obtained for each slice, when there was difference among mesial and distal pits. Mean score was calculated for each specimen. Statistical analysis was performed using SPSS 20.0 (Kruskal Wallis and Mann-Whitney tests).
Result: Ascending microleakage scores between the groups were 2<4<3<1. Statistical difference was observed between Group 1 and 2 (p<0.05), Group 2 and 3 (p<0.05).
Conclusion: Type of surface preparation plays an important role in pit-and-fissure sealants retention. The use of a primer resulted in better sealing, while self-adhering material showed worse behavior in terms of microleakage. Shade selection is not significantly involved in marginal sealing quality.