Effects of subpressure on the sealing ability of dental sealant in vitro

Comparative Evaluation of the Microleakage and Shear Bond Strength of Three Filled Pit and Fissure Sealants Using Subpressure and Adhesive System: An Experimental Analysis

Introduction

Pit and fissure caries account for about 90% of caries in children and adolescents. Sealant application may be a preventive conservative approach. But it's still challenging to bolster the retention of the filled sealant and to chop back the microleakage.

Aim

Aim is to evaluate and compare the microleakage and shear bond strength (SBS) of three filled pit and fissure sealants (PFS) using a subpressure and adhesive system: an experimental analysis.

Materials and methods

A total of 90 orthodontically extracted premolars were prepared for microleakage and SBS and divided according to materials and subgroups. Group I: resin-based filled PFS, group II: resin-modified glass ionomer-based filled PFS, and group III: giomer-based filled PFS. Subgroup 1: only sealant application, subgroup 2: subpressure application, and subgroup 3: adhesive system + subpressure application. Samples were subjected to thermocycling. Microleakage was assessed with a dye penetration method under a stereomicroscope, and SBS was assessed with a universal testing machine.

Statistical analysis and results

Unpaired t-test and one-way analysis of variance (ANOVA) test were used for analysis. Significant when p < 0.05. The SBS showed significant results for subpressure application and giomer-based filled PFS with p < 0.05. The microleakages score differed significantly for the subpressure application group with p < 0.05. Giomer-based filled PFS showed the least microleakage score.

Conclusion

This study concluded that giomer-based filled PFS showed statistically significant results. The subpressure technique significantly reduces microleakage and increases SBS.

How to cite this article

Waghmode SK, Devendrappa SN, Hadakar SG, et al. Comparative Evaluation of the Microleakage and Shear Bond Strength of Three Filled Pit and Fissure Sealants Using Subpressure and Adhesive System: An Experimental Analysis. Int J Clin Pediatr Dent 2023;16(S-1):S97-S100.

Improvement of Pit-and-Fissure Sealant Bonding to Enamel with Subpressure Treatment

This research evaluated the effects of subpressure on the shear bond strength (SBS) of 80 specimens with flat enamel surfaces and on AgNO₃ microleakage of 40 specimens with flat enamel surfaces and 40 specimens with 1 mm deep cavities before and after thermocycling. The enamel of 168 specimens was grounded to a flat surface. Two types of sealants (E and H) were selected. Sealants were applied to enamel surface (88 specimens, group F) either subjected or not to subpressure. The bonding interfaces were observed using scanning electron microscopy (SEM) and the SBS was examined using a universal testing machine before and after thermocycling. The failure mode was also analyzed. For the microleakage test, 80 specimens were grouped as group A (original enamel flat surface) and group B (a round cavity of 1 mm in depth) (40 per group). Sealants were applied to the teeth either subjected or not to subpressure. The specimens were submitted to a microleakage protocol with AgNO₃ and analyzed before and after thermocycling. Statistical analysis was performed for the data. The results showed that subpressure eliminated voids on the interface between the enamel and sealants and significantly enhanced specimens' SBS. Although thermocycling reduced SBS significantly, specimens under subpressure after thermocycling still showed higher SBS than specimens under nonsubpressure before thermocycling. The subpressure groups showed a lower microleakage level compared to nonsubpressure groups, though thermocycling caused deeper silver infiltration. In addition, different sealants showed no significant effect on the SBS and microleakage performance. Overall, subpressure application improves sealant bonding and retention rate and has potential to prevent secondary caries.