Purpose: To determine the impact of light curing of bonding agents on the microtensile bond strength (MTBS) of sealants on extracted teeth.
Methods: Flat enamel surfaces were created on 54 extracted, sound human molars by sequential grinding. Three different sealants- Clinpro (3M ESPE), Ultraseal XT Hydro (Ultradent), and Fluorshield VLC (Dentsply)- were placed after acid etching without a bonding agent (control) or with three different bonding agents - Adper Single Bond Plus (3M ESPE), Peak Universal Bond (Ultradent), and Prime&Bond Elect (Dentsply)- each in both light-cured and uncured form. The teeth were sectioned into bar specimens and the MTBS of each specimen was measured. The bond strength data were analyzed using two-way analysis of variance and Tukey's test (P=0.05).
Results: There was no significant difference between the MTBS of sealants in the thermocycled and non-thermocycled groups. The uncured adhesive had the lowest bond strength in each group, except for Clinpro after thermocycling. Teeth with uncured adhesive exhibited significantly lower bond strength in the Ultraseal (no thermocycling) and Fluroshield (with thermocycling) groups (P=0.02 and P=0.001, respectively).
Conclusions: Adding bonding agents without curing before sealant placement weakened the microtensile bond strength. There was no significant difference in MTBS between the thermocycled and nonthermocycled groups.