Polymerization color changes of esthetic restoratives.

The color changes of three different types of tooth-colored restoratives during polymerization were investigated using colorimetry. L*, a*, b* color parameters of five different shades of Z100 (a mini-filled composite resin), Fuji II LC (a resin-modified glass-ionomer cement), and Dyract (a polyacid-modified composite resin) were taken precure and postcure. The results showed that the restoratives evaluated all underwent color changes during polymerization. The polymerization changes in color parameters were shade and not material dependent. Changes in L* parameter or lightness during polymerization were significant for all material and shade combinations and had the greatest influence on the overall polymerization color change. As the color change was perceivable by the human eye for most shades of materials, the clinical practice of polymerizing some material on, or adjacent to, the undried tooth to confirm shades of esthetic restoratives before restorative procedures is prudent.