The effect of bleaching agents on mercury release from spherical dental amalgam.

To investigate the effect of carbamide peroxide, hydrogen peroxide, and over-the-counter home bleaching products on the release of mercury from spherical dental amalgam, 150 uniform amalgam specimens were prepared in clear acrylic blocks, aged for one week at 37 degrees C, and placed into individual polystyrene jars containing 20 mL of sterile saline. The specimens were divided into three groups of 50 and bleached in eight-hour cycles. All groups exposed to bleach showed increased mercury release over time.