Protocol for the Safe Removal of Mercury Fillings
By Mina Levi, DDS, 09/11/2014


Amalgam fillings, or silver colored fillings, are seen every day in many patients’ teeth from prior years’ dental work. Amalgam fillings have mercury in them, which is a toxic chemical when exposed to the body. Finished amalgam emits mercury vapor for extended periods of time, and when it is in someone’s mouth for extended periods of time, it can leak and seep into a patient’s bloodstream. It is a more and more common practice to use metal-free dentistry, like the dental procedures performed by Dentist San Francisco Mina Levi, DDS, and to remove amalgam fillings from patients’ mouths. The practice of removing amalgam fillings needs a strict protocol in order to protect the patient and the dental team from the mercury vapors of amalgam fillings. The protocol outlined by the International Academy of Oral Medicine and Toxicology is as follows:

Mercury free dentist San Francisco

Cut and chunk, keep it cool
If you remove an old amalgam by slicing across it and dislodging big chunks, you will aerosolize less of the contents than if you grind it all away. If you keep it under a constant water spray while cutting, you will keep the temperature down, and reduce the vapor pressure within the mercury. The dental hand pieces used for mercury removal in the office of Dentist San Francisco Mina Levi, DDS spray water as they cut, and suction is used constantly.

Suction!
The best tool for removing mercury vapor and amalgam particulates from the operating field is high volume evacuation (HVE).  It is kept going next to the patient’s tooth until the dentist is finished with the removal and clean-up process. 
Some dentists hate rubber dams, while others can’t live without them. A rubber dam will help contain the majority of the debris of amalgam grinding, among its many other benefits. Isolite system can also be used in place of a rubber dam, which is what is used at the dental office of Dentist San Francisco Mina Levi, DDS. But you must know that mercury vapor will diffuse right through the dam, and some of the particulates will often sneak past it, too.  So:
  • Always use a saliva ejector behind the dam to evacuate air that may contain mercury vapor. Nitrile dams are better vapor barriers than latex.
  • Rinse well as you go, especially under the rubber dam clamp, because amalgam particles left on the used dam will emit mercury from your garbage can.  (If you wipe your dirty mirror on a gauze square or the patient’s bib, that gray smear also emits quite a lot of mercury vapor!)
  • As soon as the amalgams are out, remove the dam and thoroughly rinse the patient’s mouth before placing the new restorations.  It can take as much as sixty seconds of rinsing to fully remove the mercury vapor.  Search for gray particles.  If there are particles on the back of the tongue, have the patient sit up and gargle them out.
  • Post-removal rinses can be used to scavenge mercury from the patient’s saliva. Some of the substances that can be suspended in water and used for this purpose are activated charcoal, chlorella, or n-acetyl cysteine.
If you don’t use a rubber dam, you must be vigilant with the HVE, and take frequent breaks to thoroughly rinse the field.  Either way, the “Clean-Up” suction tip reduces the  dispersion of particulates in the area.

Supplemental air
Upon request, the patient can be provided with piped–in air, so they do not have to breathe the air directly over the mouth during amalgam removal.  A positive pressure respiration device such as a nitrous oxide nose hood, or a similar ventilation device, is probably the best way to provide clean air.
If you have any questions about mercury removal or metal-free dentistry, visit Dentist San Francisco Mina Levi, DDS on the web at www.minalevidds.com or give us a call at (415) 513-5066.