Influence of staining solutions and whitening procedures on discoloration of hybrid composite resins.

Objectives: The aim was to evaluate the color stability and water uptake of two hybrid composite resins polymerized in two different conditions after exposure to commonly consumed beverages. In addition, the effect of repolishing and bleaching on the stained composite was evaluated.

Methods: Eighty specimens (12 mm × 12 mm × 3 mm) were made from two hybrid composite resins of shade A2.