EFFECT OF ELECTRONIC CIGARETTES SMOKING ON COLOR STABILITY OF CAD/CAM ACRYLIC RESIN: IN VITRO STUDY

INTRODUCTION: The most common electronic nicotine delivery system is electronic cigarettes. Most of electronic cigarettes consist of a battery and electric heater used to aerosolize a liquid to produce vapor which the user inhales. Poly methyl methacrylate comes in contact with a variety of foods and beverages of different temperatures, as a result, it is prone to absorbing a variety of pollutants, altering its physical structure and appearance. OBJECTIVES: This study aimed to investigate the effects of electronic cigarettes smoking on color stability of CAD/CAM acrylic resin. MATERIAL AND METHODS: This study was in vitro study in which sixty specimens of CAD/CAM acrylic resin was exposed to aerosols which were flavored and non-flavored with nicotine content (0 mg, 6 mg and 12 mg). A portable suction machine was modified to simulate smoking in vivo. Each specimen was exposed to 20 cycles of aerosol released by a single ECIG device using the smoking chamber. Color measurements were performed using a calibrated spectrophotometer on the specimens before and after ECIG exposure RESULTS: Specimens exposed to flavorless 0 mg. nicotine aerosol showed the lowest delta E value 2.39 (±0.16) , while Specimens exposed to flavored 12 mg. nicotine showed the highest values 4.14 (±0.19). No significant difference in color change found between groups exposed to flavorless e-liquid, while a significant difference found between flavored 0 mg. nicotine and 12 mg. nicotine groups (P = 0.002).Also, a significant difference found between flavored 6 mg. nicotine and 12 mg. nicotine groups (P = 0.002). According to Two Way ANOVA, both flavor and nicotine contents have a significant effect on color change (P <0.0001). CONCLUSION: Exposure to flavored and non-flavored electronic cigarettes aerosol of different nicotine concentrations changed the color of acrylic resin. Both flavor and nicotine contents have a significant effect on color change.