Aim: This was to evaluate the microleakage of 3 different sealants, applied on sound and questionably carious occlusal surfaces with and without a bonding agent.
Methods: A total of 120 human molars were selected, photographed with a digital video microscope, and assigned by 3 independent examiners, according to the criteria of ICDAS II, in 2 groups of 60 teeth each. Group A: teeth with deep, clear, sound occlusal surfaces (ICDAS II, code 0). Group B: teeth with questionable occlusal surfaces, having deep, stained pits and fissures with probable incipient, but non-cavitated carious lesions (ICDAS II, codes 1 and 2). Each group was divided into 2 subgroups of 30 teeth each (bonding or no bonding) and then into 3 subgroups of 10 teeth each according to the type of sealant used: one conventional (Conseal) and 2 fluoridated (Conseal F and Teethmate F). After the application of the bonding agent and the sealant to the appropriate teeth, all specimens were subjected to thermal cycling and immersed in a 10% methylene blue dye solution for 4 hours. Average and summed microleakage for each sample were estimated from dye penetration scores on 3 mesiodistal sections of the tooth across the sealed occlusal surface. Non-parametric Friedman's 2-way ANOVA by ranks and Conover-Inman pair wise comparisons were used for differences at the 0.05 level of significance.
Results: According to Friedman's 2-way ANOVA by ranks analysis, although there were no significant differences between the different sealants (chi(2) = 0.048, df = 2, P = .976), there were significant differences between the sound and questionably carious occlusal surfaces (chi(2) = 24, df = 3, P = .000). Conover- Inman pair wise comparisons showed no differences between the groups using and not using bonding agents, on sound (SNB-SWB, P = .4561) or questionable occlusal surfaces (QNB-QWB, P = .0842).
Conclusions: Sealant microleakage on questionably carious occlusal surfaces was statistically significantly higher than that of sound occlusal surfaces. Using a bonding agent or fluoridated FS did not influence microleakage significantly, either on sound or on questionable fissured surfaces.