Interaction of peroxides with amalgam: a case report

Area of Science:

• Dental Materials Science
• Cosmetic Dentistry

Background:

• Nightguard vital bleaching using 10% carbamide peroxide is a common cosmetic dental procedure.
• Previous studies indicated minor effects of bleaching agents on amalgam, primarily mercury release.

Observation:

• A case report documented unusual staining of a bleaching tray in the area of upper first molars with amalgam fillings.
• These specific amalgam restorations exhibited superficial chipping at their cavosurface margins.
• No staining occurred with amalgam restorations lacking marginal defects or in other areas of the mouth.

Findings:

• The observed amalgam staining of the bleaching tray suggests a potential interaction between the bleaching agent and defective amalgam restorations.
• The integrity of the cavosurface margin appears critical in this interaction.

Implications:

• Amalgam restorations with defective cavosurface margins require careful monitoring during tooth whitening therapies.
• Replacement of compromised amalgam restorations with composite resin prior to bleaching may be advisable to prevent adverse effects.