Effects of Cigarette Smoke and e-cigarette Aerosol on Composite Resin

Objectives: This study aimed to compare the effects of aerosols (EA) generated from a novel electronic cigarette using the MESH™ technology (Philip Morris International) with those of cigarette smoke (CS) from 3R4F reference cigarette (University of Kentucky, KY, USA) on the color and gloss of dental composite resins and to study the efficacy of whitening treatments on resins affected by CS and EA.
Methods: Forty Filtek™ Supreme Ultra (FSU) discs were prepared and divided into three groups: 15 for CS and EA groups respectively and 10 for the air control group. Exposures were performed for 56 minutes/day for 15 days with daily brushing with regular toothpaste. Two whitening sessions, including 21 days of brushing with whitening toothpaste and three days of treatments with take-home bleaching (6% hydrogen peroxide), were performed at completion of the exposure. Color and gloss were assessed before exposure, at every five days of exposure, and after each whitening session.
Results: Marked discoloration was observed in CS group (ΔE=23.66±2.31), but much less was observed in EA group (ΔE=2.77±0.75), and none was observed in the air group. Resins exposed to CS did not recover the original color after treatments with whitening toothpaste (ΔE=20.17±2.68) and take-home bleaching (ΔE=19.32±2.53), but those exposed to EA reverted to baseline after treatment with whitening toothpaste (ΔE=0.98±0.37), and no further change in color was observed following take-home bleaching (ΔE=0.98±0.45) (Table 1). Gloss of resins exposed to CS, EA, or air did not differ significantly and decreased with exposure time. The whitening treatment reverted the gloss to values close to baseline similarly for all groups (Table 2).
Conclusions: CS caused significant discoloration of dental composite resins, which was not completely reversible with whitening treatments. Mild discoloration associated with EA exposure could be reverted by brushing with whitening toothpaste alone.