Objectives.
The objective of this study was to determine the fluorescent emission of experi-
mental resin composites after addition of a fluorescent whitening agent in varied concen-
trations. The effects of thermocycling and composition of resin matrix on the fluorescent
emission were also determined.
Methods.
AnexperimentallightcuringresinmatrixwasmadebymixingBis-GMA,UDMAand
TEGDMA in the ratio of 1:1:1 by weight, and silane coated glass filler was added in the ratio of
50wt.% of resin composite. A fluorescent whitening agent [FWA, 1,4-double-(benzoxazole-
group-2-group)naphthalene] was added with the concentration of 0.01–0.1%. To determine
the difference by the resin matrix, two resin composites (60wt.% Bis-GMA or UDMA with
40wt.% TEGDMA) with the same filler content were made, and the FWA was added. Five
specimens of 2mm in thickness were made for each group. Spectral reflectance was mea-
sured relative to the illuminant D65 on a reflection spectrophotometer. From the spectral
reflectance values, the difference in reflectance (fluorescence spectra) by the inclusion or
exclusion of UV component was calculated. After the baseline measurement, thermocycling
was performed for 500 and 1000 cycles, and the fluorescent emission was measured again.
Results.
The concentration of FWA influenced the fluorescent peak heights and areas
(
p