Objective:

Sealants are used in orthodontics to help prevent demineralization during treatment. This study aimed to determine if there is a difference in the shear bond strength (SBS) between 2 different resin sealants bonded to teeth.

Methods:

Extracted human premolars (n=20/group) were randomly divided and prepared by acid etching, followed by application of primer or sealant. Group 1, the control group, used Transbond XT Primer (3M Unitek). Groups 2 and 3 were prepared with the sealants L.E.D. Pro Seal (Reliance Orthodontic Products) and Opal Seal (Opal Orthodontics) as the respective primers. Transbond XT Adhesive was applied to a stainless steel bracket and bonded to each tooth. Each group was stored in distilled water at 37°C for 48 hours before. SBS was measured using a universal testing machine, and the adhesive remnant index (ARI) was scored.

Results:

The SBS (MPa) of the groups was as follows: Group 1 (Transbond): 20.1±6.0; Group 2 (Pro Seal): 16.5±4.8; and Group 3 (Opal Seal): 15.7±3.9. The SBS of Transbond XT Primer was significantly greater than that of Opal Seal (p<0.05/analysis of variance-Tukey), while Pro Seal and Opal Seal sealants were not significantly different from each other (p<0.05). The Opal Seal group had significantly greater ARI scores, indicating that more adhesive remained on the teeth after debonding.

Conclusion:

Opal Seal and Pro Seal sealants have similar SBS but generally exhibit lower bond strengths than an adhesive primer.

Keywords: Adhesive remnant index, bond strength, orthodontic sealant