Spectrophotometric Evaluation of Direct Resin Composite Restoration after Staining and Bleaching: An In Vitro Study
Sundos Hussein Mohammed Al-Halali, Ibrahim Z Al-Shami, Abdulwahab Ismail Alkholani, Selwan Ahmed Shaiban, Hind Abdulrhman Mohammed Humaid, Fatima Mohammed Al. Rohmi
Objective: The study evaluated the discoloration effects of various staining agents, specifically coffee,
qat, a mixture of qat and red soft drink, and distilled water, on different resin-based composite materials.
Additionally, the effectiveness of an in-office bleaching agent in restoring color stability and removing
stains from these composites was assessed.
Materials and Methods: An in-vitro experimental observational study was conducted, where 60 discshaped resin composite specimens (Merfill Bulk Fill, Charm Microhybrid, Tokuyama Supra-Nano)
were immersed in the staining solutions for 7 days, followed by an in-office bleaching protocol and a
home bleaching treatment. Color measurements were taken before immersion, after staining, and postbleaching using a VITA Easy Shade V Spectrophotometer, with color differences (ΔE values) calculated.
Results: All resin composite specimens exhibited significant color changes after immersion in staining
solutions, with coffee causing the most discoloration, especially in Merfill Bulk Fill and Tokuyama
Supra-Nano composites. In-office bleaching effectively restored color stability, with the most significant
improvements seen after two applications.
Conclusion: The study confirmed that staining agents significantly affect the color stability of resinbased composites. Tokuyama Supra-Nano Composite exhibited superior stain resistance and effective
recovery post-bleaching, making it a preferred choice for aesthetic restorations. The findings emphasize
the importance of material selection and patient education regarding staining potential.
