Mercury is continuously released from amalgam fillings, and numerous research investigations have clearly shown that mercury from this source provides the major contribution to body burden of mercury. The vapour has a direct pathway to the brain. It is inhaled into the lungs, oxidized to ionic mercury and binds to cell proteins.

Due to the danger of releasing mercury by removing amalgam fillings the following is a priority order for the removal:

• Root canal-treated teeth with pins or screw-posts of non-precious metals and metal crowns with amalgam cores should be treated first.
• Next are amalgams in direct constant contact with gold. Often the amalgam can be removed while the gold inlays, the crown or the bridge, can be left. What to do with the fold can be decided later.
• Where there is direct intermittent biting contact between amalgam and gold in opposing teeth.
• Where there is direct contact between amalgam and other metals like partial chromium-cobalt dentures.
• Most patients have several different types of amalgam fillings, and the ones containing the newer types of amalgam high in copper (non-gamma-2 amalgam) should be removed first. The priority order between different filings can be based on the patient’s own opinions or visible signs of corrosion and discoloration.
• Amalgam fillings in contact with gum tissue. It might be necessary to remove metal-impregnated gum tissue surgically.