Aim: The aim of the present study was to evaluate the effect of aging on the microhardness score [Vickers hardness number (VHN)] of different resin-based fluoride-releasing sealants compared to non-fluoride resin-based sealants.
Materials and methods: A total of 48 extracted sound molars that were sectioned mesiodistally were used. In the current study, four types of sealants were compared: Group A, a resin-based non-fluoride-releasing pit and fissure sealant (Eco-S sealant) served as a control. Groups B, C, and D received resin-based fluoride-releasing pit and fissure sealants Helioseal F, Fissurit F, and Embrace™ WetBond, respectively. Subsequently, each group was further divided into immediate and aged subgroups. The samples had been evaluated regarding their microhardness using a pyramidal diamond indenter of a Vickers hardness test at two-time intervals: Immediately and after the aging process through thermocycling.
Results: There were no statistically significant differences between mean VHN and material types (p = 0.72). Aging appeared to significantly increase the mean VHN (p = 0.001). The interaction model between material type and time factor showed that the effect of aging differs by the material type, where the VHN of the Embrace™ group increased significantly after aging from 24.33 ± 5.60 to 31.70 ± 3.59 (p = 0.001).
Conclusion: While there were no significant differences in the microhardness of commonly used fluoride-releasing fissure sealants, time appears to significantly increase the mean microhardness score (VHN), especially in the Embrace™ group.
Clinical significance: Embrace™ WetBond fissure sealant showed a significant improvement in the mean microhardness score (VHN) with time. However, clinical studies with long-term follow-up are needed to confirm our results.
Keywords: Aging; Fissure sealant; Microhardness Resin-based fluoride-releasing sealants..