International Academy of Oral
Medicine and Toxicology
Protocol for Mercury/Silver Filling Removal
First in every concerned doctor's mind is the
protection of the patient from additional
exposure to mercury. This is especially true of
the mercury toxic patient. The mercury toxic
patient may have been exposed to varying amounts
of mercury from diet, environment, employment or
from mercury/silver dental fillings. All forms
are cumulative and can contribute to the body
burden. The goal of this preferred procedure
is to minimize any additional exposure of the
patient, ourselves, or staff to mercury.
During chewing the patient is exposed to
intraoral levels which are several times the EPA
allowable air concentration. 2
During the removal or placement of amalgam the
patient can be exposed to amounts which are a
thousand times greater than the EPA allowable
Once the drill touches the filling temperature
increases immediately vaporizing the mercury
component of the alloy. There are 8 steps to
greatly reducing everyone's exposure.
1. Keep the fillings cool
All removal must be done under cold water spray
with copious amounts of water.
Once the removal has begun, the mercury vapor
will be continuously released from the tooth.
2. Use a high volume evacuator
Therefore, a high volume evacuator tip should
be kept near the tooth (1/2 inch) at all times
to evacuate this vapor from the area of the
patient. Polishing amalgam can create very
dangerous levels of mercury and should be
avoided especially for the mercury toxic
3. Provide an alternative air source
All patients having amalgam removed or placed
should be provided with an alternative air
source and instructed to not breathe through
their mouth during treatment. A nasal hood such
as is used with the nitrous oxide analgesia
equipment is excellent. Air is best and oxygen
is acceptable although not required. If just air
is used it should be clean and free of mercury
vapor preferably from outside the dental office.
4. Immediately dispose of the mercury alloy
Particles of mercury alloy should be washed
and vacuumed away as soon as they are generated.
The filling should be sectioned and removed in
large pieces to reduce exposure.
At present the International Academy of Oral
Medicine and Toxicology (IAOMT) has approved
removal both with and without the use of a
rubber dam. Some evidence exist to support both
views since high levels of mercury and amalgam
particles can be found under the dam. All
members are agreed that whether or not a rubber
dam is used the patient should be instructed to
not breathe through their mouth or swallow the
particles. Some experts feel that it is better
to remove the amalgam first and then apply the
dam if needed for restorative procedures.
5. Lavage, and change gloves
After the fillings have been removed, take
off the rubber dam if one was used and lavage
the patients mouth for at least 30 seconds with
cold water and vacuum. Remove your gloves and
replace them with a new pair. If a restorative
procedure is next then reapply a new dam and
6. Immediately clean patient
Immediately change patient's protective wear
and clean their face.
7. Consider nutritional support
Consider appropriate nutritional support
before, during and after removal.
8. Keep room air pure
Install room air purifiers or ionizers and
fans for everyone's well being.
requires that employees be given written
informed consent before the use of any toxic
chemicals of which mercury is one. Elemental
mercury vapor is one of the most toxic forms of
mercury and should not breathed. Women of child
bearing age should be exposed to no more than
10% of the OSHA MAC6.
Women who are pregnant should be exposed to no
If you use mercury or remove mercury in any form
the National Institute of Occupational Safety
and Health (NIOSH) has recommended that your
employees be medically monitored annually.
ANY MERCURY EXPOSURE REQUIRES THAT THE
EMPLOYEE WEAR AN APPROVED MERCURY FILTER MASK.
An approved mask is appropriate for wearing
during all dental procedures which will expose
you or your staff to mercury.8
The manner in which dentists operate their
equipment dramatically affects the amount of
mercury released. Never drill on mercury high
dry. It is hazardous to you, your staff, and
your patient. Levels as high as 4000 m g/M3 have
been measured 18" from the drill when used
high dry. Levels over 1000 m g/M3 are measurable
upon opening an amalgam mixing capsule.
One out of 7 California dental offices tested
over the OSHA TWA of 50 m g/M 3 . 100% of the
vacuum cleaner exhaust tested over 100 m g/M 3 .
Any office where mercury is used should be
tested regularly and staff should be monitored
for exposure. Testing services are available
and a mercury sensor badge is available for
personnel monitoring. They should test inside
storage areas and along baseboards where mercury
might have dropped. Office spills can go
undetected for years and are extremely
1 IAOMT Standards of Care
Preferred Procedure Approved 9/27/92
2 EPA United States
Environmental Protection Agency Office of Health
and Environment Assessment Mercury health
effects update Final Report EPA-600/8-84-019F
3 Cooley RL, Barkmeier WW:
Mercury vapor emitted during ultraspeed cutting
of amalgam. J Indiana Dent Assoc 57:28-31, 1978
4 OSHA Job Health Series:
5 Hazard Communication
Program Federal Register/ Vol. 52. No. 163 /
Monday, August 24, 1987
6 OSHA MAC is Threshold Limit
Value of 100 micrograms/ cubic meter or 100 PPM
This is a never to be exceeded standard.
7 Koos BJ and Lango LD ,
Mercury Toxicity in the pregnant woman, fetus,
and newborn infant. A review Am J Obstetrics and
Gynecology 126(3):390-409, 1976
8 Mine Safety Association
high levels and 3M mercury dust mask lower