Dental amalgam is a commonly used material for filling cavities, consisting of a mixture of metals including approximately 50% elemental mercury, combined with silver, tin, and copper.
Why Mercury Is Used
Mercury binds the alloy particles into a durable, solid filling.
It is cost-effective and easy for dentists to place quickly.
Has a long history of clinical use and wear resistance.
Risks of Mercury Amalgam
Mercury vapor is continuously released from amalgam fillings – especially during chewing, brushing, or teeth grinding. This vapor can be inhaled and absorbed into the bloodstream, potentially accumulating in tissues.
Immunological effects – autoimmune reactions in sensitive individuals
Renal burden – low-level excretion through kidneys over time
When dentists prepare dental amalgam for placement, the alloy powder is mixed with liquid elemental mercury using a mechanical device called a triturator. This process creates a pliable mixture that is packed into the tooth. During this phase, precautions are necessary to reduce mercury vapor exposure in the clinical environment:
Pre-measured sealed capsules reduce mercury spills and handling errors.
Mixing is performed in a closed chamber to minimize aerosolization.
Amalgam is inserted promptly and excess material removed quickly to limit vapor release.
Dental offices often use amalgam separators in waste systems to prevent mercury from entering the water supply.
Some practitioners use high-volume evacuation systems during placement, though this is not universally adopted.
Regulatory Stance and Public Health Guidance
FDA (2020): Advises against use in pregnant women, children, and those with pre-existing neurological or kidney issues. [FDA Guidance]
EU Regulation: Bans amalgam use in children under 15 and pregnant/breastfeeding women.
IAOMT: Recommends mercury-free dentistry and safe removal protocols. [SMART Protocol]
Alternatives to Amalgam
Composite resins – Tooth-colored, mercury-free
Glass ionomer – Releases fluoride but less durable
Ceramic or gold inlays – Longer-lasting but costlier
Safe Removal Protocols
Removing amalgam fillings must be done cautiously to avoid releasing large amounts of mercury vapor and particulate matter. The International Academy of Oral Medicine and Toxicology (IAOMT) has developed the SMART protocol (Safe Mercury Amalgam Removal Technique) to minimize exposure.
Use of a rubber dam to isolate the tooth and block inhalation or swallowing of particles.
High-volume suction with a mercury separator to capture vapor and debris.
Supplemental oxygen through a nasal mask to avoid breathing contaminated air.
Chopping amalgam into chunks to reduce drilling and heat, which increases vaporization.
Use of activated charcoal or other binders before and after the procedure to support detox.
Proper ventilation and air filtration systems in the dental office.
IAOMT's full SMART protocol can be reviewed at iaomt.org.