Comparison of release of mercury from three dental amalgams

Abstract

Mercury release from dental amalgams has generated considerable concern in recent years and is the subject of this study. Specimens of one admixed high-copper amalgam (Contour), one lathe-cut low-copper amalgam (SDI), and a new tin- and copper-free amalgam claimed to be non-mercury-releasing (Composil) were evaluated for release of mercury when incubated in purified water at 37°C. Measurement of mercury was done by cold-vapor atomic absorption spectrophotometry, and the amount released was expressed as μg/cm2/24 hr. Study was conducted over a four-week period. Results show that Contour and SDI released similar insignificant amounts (mean release of < 0.1 μg/cm2/24 hr) compared with Composil (mean release of 41.0 μg/cm2/24 hr). The difference in release by Composil compared with that by Contour and SDI is highly significant (P < 0.001). The implications of chronic release of mercury from dental amalgams are discussed. Long-term release studies are in progress. © 1989.