Removing Amalgam Fillings Safely to Reduce Mercury Exposure
It used to be that standard procedure was to cut amalgam with adentalbur, but we now know that increases risks of exposure. Thedentalbur releases particles with a wide surface area, with up to a three or four fold increase of mercury in blood plasma measured the next day!The trouble isnt the filling itself, but the particulates released whendentistsattempt to remove it. These particulates are almost 1 micron or less in size, but they can be absorbed through the respiratory system during a procedure. When the patient inhales, the particles get trapped deep within the lungs, which can lead to an exposure that is more than 100 times greater than the vapor produced by a bur.
Fortunately, there are some procedures that reduce this risk significantly for everyone involved.
Cutting and Chunking
Dentistscan remove amalgam by slicing across it, which basically breaks the amalgam into chunks. The chunks dont allow as many particulates to become aerosolized in the air, which significantly reduces exposure. However, there is still a danger of vapor pressure building up if the filling gets too hot. The solution is to continually blast the filling with water to reduce the temperature as you cut.
The Role of Suction
Suction dramatically reduces the amount of vapors and particulates floating around while you work on the patient. Keeping suction near the filling as you remove it will also help with the cleanup process. Just make sure your pump discharges into a space that is safe for mercury vapors, and avoid discharging those particulates into your lab or utility room.
Use the Clean Up suction tip, with a small enclosure on the end, to surround the tooth and suck up all those particulates efficiently. You can purchase these tips online, or through your local distributors.
Using a Rubber Dam
The bottom line is that removing amalgam will reduce exposure to mercury, but there is some evidence to suggest that a rubber dam might help the situation. Somedentistswont want to hear it, as dams can be difficult to work with, but using a rubber dam might be crucial to removing amalgam safely.
Dams arent the end-all solution, as the mercury will diffuse through it. If you use a dam in conjunction with a saliva ejector, you can reduce the risk. You can also opt to use a nitrile dam, which stops vapors much more efficiently than latex.
Those who still refuse to use a dam should take breaks throughout the procedure. Also, be sure to cover the patients face as exposed skin can come into contact with amalgam particles that become dislodged during the procedure. All staff should have on rubber gloves during any procedure, and its a good idea to pipe air in from the outside so no one has to breathe the mercury contaminated air in the operating room.
