Mercury-containing dental fillings release small amounts of mercury. Randomized clinical trials demonstrate that the mercury present in fillings does not produce illness. Removal of such fillings is unnecessary, expensive and subjects the individual to absorption of greater doses of mercury than if left in place. Furthermore, placement of composite resin restorations are known to cause a transient increase in urinary Bisphenol-A levels, for which there are unknown health effects and high quality evidence suggests higher failure rates in composite resins versus filling restorations.
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