Penetrability and Microleakage of Resin Infiltrant Versus Ion-Releasing Resin Sealants on Occlusal and Proximal Surfaces of Permanent Teeth.

Purpose: To compare microleakage resistance of resin infiltrant versus ion-releasing resin sealants on occlusal and proximal surfaces of permanent teeth and evaluate penetrability on occlusal surfaces while determining fissure morphology influence. Methods: Fifty-six extracted human premolars with International Caries Detection and Assessment codes 0 to 2 were randomly divided into occlusal (n=28) and proximal (n=28) groups, with 4 subgroups per surface (n=7 each) receiving 3 ion-releasing resin sealants (SealRite™, Embrace™ WetBond™, and BioCoat™) and Icon® resin infiltration. Following manufacturer protocols, specimens underwent thermocycling (500 cycles) and 24-hour methylene blue dye immersion at 37°C. Microleakage was assessed under stereomicroscopy following buccolingual sectioning for occlusal and mesiodistal sectioning for proximal surfaces. Penetrability was measured and compared according to material and fissure morphology. Statistical analysis employed Kruskal-Wallis and Dunn???s post-hoc tests for microleakage, and analysis of variance with post-hoc analysis for penetrability. Results: Icon® and BioCoat™ demonstrated significantly superior microleakage resistance compared to SealRite™ and Embrace™ WetBond™ on occlusal surfaces (P=0.001). On proximal surfaces, Icon® outperformed both conventional sealants, while BioCoat™ significantly exceeded only Embrace™ WetBond™. Critically, fissure morphology-not material type-significantly influenced penetrability (P=0.017), with V-shaped fissures exhibiting superior penetrability (95.55±7.24%) compared to I-shaped (75.26±17.62%) and IKshaped configurations (62.74±10.18%). Conclusion: Icon® demonstrates superior sealing properties across both surfaces, while BioCoat™ represents a viable ion-releasing alternative. Fissure morphology emerges as the critical determinant of penetration effectiveness, suggesting that preparatory techniques merit investigation for challenging configurations in early carious lesions. Long-term clinical validation and 3D imaging studies are essential to confirm these findings.