Effect of Dental Headlamp and Blue-Blocker on Pre-mature Sealant

Objectives: To compare the effects of exposure to dental headlamp source and Blue-Blocking filter on premature curing of a variety of commercial pit-and-fissure sealants.
Methods: Thin (≈0.1mm) specimens of uncured commercial pit-and-fissure sealants (Bis-GMA-containing: Clinpro (3M/ESPE), Ultraseal XT (Ultradent); Non-Bis-GMA-containing: Embrace (Pulpdent), Toothfairy (Septodont)) were placed on the diamond element of a temperature-controlled (30°C) ATR stage of an FTIR spectrometer. Specimens were exposed to light from an LED-based dental headlamp (RADBL23, Q-optics, at 16”) for 80s. Real-time infrared spectra were obtained (1 scan/s, resolution 2 cm^-1), from which monomer conversion values were determined. N=5/group, specimens made in randomized order. The process was repeated, with the Blue-Blocking filter of the light in place. The time at which specimens first demonstrated onset of conversion was noted and compared within the presence or absence of the Blue-Blocker filter among sealant composition and product, using a 2-way ANOVA. The Tukey test was used to compare mean pairs. T-tests compared onset times of the same material between use of Blue-Blocker. Pre-set alpha was 0.05.
Results: Table presents results. For the 2-way analyses, all factors, and their interaction term, demonstrated significant influences on onset time (p<0.001). Thus, two 1-WAY ANOVAs among pooled groups within a Blue-Blocker group were performed. When no blue blocker was present, Toothfairy had a significantly shorter onset time (p<0.001) than the other products, which were not different. When using the Blue-Blocker, no detectable cure occurred during headlamp exposure.
Conclusions: Dental sealants can start to prematurely cure from headlamp exposure within 8 to 13 seconds, but use of Blue-Blocker filters prevents curing for at least up to 80 seconds.