A comparative evaluation of shear bond strength of different pits and fissure sealants: an in vitro study

In Vitro Evaluation of Viscosity, Depth of Penetration, Microleakage, and Shear Bond Strength of Conventional and Hydrophilic Sealants

Background

Sealants are effective in preventing and arresting pit and fissure caries. Newer brands of sealants continue to be developed despite the lack of scientifically based information addressing the caries-preventive properties of these materials. Hence, laboratory in vitro tests play a vital role in providing the necessary information regarding the efficacy of new products in a short period of time.

Objectives

To compare and evaluate the viscosity, resin tag length, microleakage, and shear bond strength between conventional and hydrophilic sealants.

Materials and methods

A total of 40 extracted third molars were selected. Only 20 were evaluated for microleakage and resin tag length and another 20 for shear bond strength evaluation between group I-ClinPro and group II-UltraSeal XT hydro. After sealant placement, specimens were immersed in 0.1% rhodamine dye, followed by thermocycling. Microleakage testing was done using a confocal laser scanning microscope and resin tag length evaluation using a scanning electron microscope (SEM) and shear bond strength using an Universal Instron machine. Viscosity was assessed using an Anton Paar viscometer. Results were subjected to statistical analysis using Statistical Package for the Social Sciences (SPSS) software version 20.

Results

Viscosity and mean microleakage scores for group I (0.92 MPa and 1.50) were found to be higher than for group II (0.72 MPa and 0.60). Mean resin tag length and mean shear bond strength for group I (7.46 ± 0.95 μm and 13.71 ± 0.94 MPa) were found to be less compared to group II (10.03 ± 1.00 μm and 20.39 ± 0.98 MPa). The results were found to be statistically significant (p < 0.05).

Conclusion

Group II was found to be less viscous, which resulted in the formation of resin tags of sufficient length and showed less microleakage and higher shear bond strength than group I.

How to cite this article

Prabakar J, Jeevanandan G, Kengadaran S. In Vitro Evaluation of Viscosity, Depth of Penetration, Microleakage, and Shear Bond Strength of Conventional and Hydrophilic Sealants. Int J Clin Pediatr Dent 2023;16(5):745-750.

Effect of Different Etching Times on Pit-and-Fissure Sealant Micro-Shear Bond Strength to the Enamel of Primary Teeth

Successful clinical use of pit-and-fissure sealants relies on the sufficient etching of the enamel, field isolation and sealant retention. The etching time changes the physical and mechanical surface properties of the etched tooth tissues; therefore, it impacts both etching depth and the bond strength of sealants to the enamel. We examined if reducing the recommended 15 s etching time of primary teeth enamel affects the micro-shear bond strength (µSBS) of pit-and-fissure sealants. The cusps of forty non-carious, extracted human primary molars were separately etched for 8, 15 or 30 s. Then, a pit-and-fissure sealant was placed and light-cured. The µSBS values were evaluated and compared among the three groups. The mean µSBS values ± standard deviations were 34.68 ± 16.93, 34.19 ± 17.35 and 36.56 ± 16.57 MPa in the cusps etched for 8, 15 and 30 s, respectively. No statistically significant differences in µSBS were observed among the three test groups. In this study, we showed for the first time that the recommended etching time of primary teeth enamel may be reduced from 15 to 8 s without compromising the µSBS of the sealant. Further evaluations in a clinical setting are warranted.