Factors affecting mercury release from dental amalgam exposed to carbamide peroxide bleaching agent.

Factors affecting mercury release from dental amalgam exposed to carbamide peroxide bleaching agent.: "Factors affecting mercury release from dental amalgam exposed to carbamide peroxide bleaching agent.
Rotstein I, Avron Y, Shemesh H, Dogan H, Mor C, Steinberg D
Am J Dent. 2004 Oct ; 17(5): 347-50

PURPOSE: To assess, in vitro, the effects of aging and surface polishing on mercury release from dental amalgams exposed to 10% carbamide peroxide at two pH levels. METHODS: Samples of fresh and aged amalgam, polished and unpolished, were treated with 10% carbamide peroxide at pH 4.5 and at pH 6.5 for periods of 1, 4, 7, 10 and 13 days. At each time period, mercury concentrations in solution were measured using a cold-vapor atomic absorption mercury analyzer system and compared to control samples treated with phosphate buffer. RESULTS: Amalgam samples exposed to 10% carbamide peroxide released significantly more mercury in solution than samples exposed to phosphate buffer controls. Mercury release was time-dependent and significantly higher in aged amalgam than in fresh amalgam (P < 0.001). Mercury release was also pH-dependent and higher in unpolished amalgam.

Uh Oh! More mercury with older aging amalgams bleaching.

Will this mean bleaching only teeth without amalgams or replacement of amalgams before bleaching?

Time will tell!