What does the FDA say about amalgam for higher-risk groups, and does it apply to me?

What the FDA recommended in 2020

Dental amalgam is a mixture of metals, roughly half of it elemental mercury bound to a powder of silver, tin, copper and sometimes zinc. Once set, it is a hard, durable filling, but it releases very low levels of mercury vapor, most noticeably when a filling is placed or drilled out and, to a smaller degree, during chewing.

In September 2020 the FDA reviewed what is known about that exposure and issued a recommendation aimed at groups it considers potentially more susceptible to mercury's effects or for whom the long-term evidence is thin. For these groups the FDA advises avoiding new amalgam fillings whenever possible and appropriate, and using non-mercury alternatives such as composite resin or glass ionomer cement:

• Pregnant women and their developing fetuses, and women who are planning to become pregnant.
• Nursing women and their newborns and infants.
• Children, especially those younger than six.
• People with pre-existing neurological disease, such as multiple sclerosis, Alzheimer's disease or Parkinson's disease.
• People with impaired kidney function.
• People with a known heightened sensitivity or allergy to mercury or to the other components of amalgam, such as silver, copper or tin.

The FDA paired that advice with a second statement that is just as important: if an existing amalgam filling is in good condition with no decay beneath it, the agency does not recommend removing or replacing it, because removal results in unnecessary loss of healthy tooth structure and a temporary rise in mercury vapor exposure during the drilling. Both parts of the recommendation apply to the higher-risk groups. The first is about new fillings; the second is about fillings you already have.

What the recommendation is, and what it is not

The FDA's 2020 advice is best read as a precaution. It did not report new evidence that amalgam had harmed people in these groups. Its stated reasoning was that developing nervous systems may be more sensitive to mercury vapor, that mercury can accumulate in the body, and that very little long-term clinical data exists for these specific populations. At the same time, the FDA said the majority of evidence suggests that exposure to mercury from dental amalgam does not lead to negative health effects in the general population, and it did not ban amalgam or restrict its use for people outside these groups. The NIDCR and the ADA take a similar position: current evidence does not show that the low-level mercury exposure from amalgam is harmful to health, and sound fillings do not need to come out.

Two distinctions help when reading about this topic:

• Precaution is not proof of harm. Advising a group to avoid an exposure where data are limited is different from concluding that the exposure causes disease in that group.
• Association is not causation. Studies that find a link between the number of fillings and a symptom cannot by themselves show that the fillings caused it, because people with more fillings also differ in age, health and many other ways.

Loul Dental Studio does not claim that avoiding amalgam, or replacing it, treats, improves or prevents any kidney, neurological or other medical condition, and offers no "detox" or symptom-relief promises. The office lists mercury-free restorations among its services; for new fillings in the groups above, that is consistent with the FDA's recommendation. For the broader distinction between "mercury-free" and "metal-free", see our guide on metal-free versus mercury-free dentistry.

Group by group: what to tell your dentist and your physician

Pregnancy, planning a pregnancy, and nursing

The FDA advice concerns new fillings placed during pregnancy or breastfeeding, or while you are trying to conceive. It does not suggest that existing fillings be removed during pregnancy; the drilling itself is the moment of highest vapor release. Dental care during pregnancy is encouraged by dental and obstetric organizations, and needed fillings can usually be planned around the pregnancy with your obstetric provider's input. Tell the office if you are pregnant, planning to be, or nursing, and share your obstetric provider's name so questions about timing can be coordinated. Nothing on this page replaces that conversation.

Children, especially under six

For a child who needs a filling, the FDA advice points toward composite resin or glass ionomer where the tooth and the situation allow. The choice still depends on where the cavity is, how large it is, and how well the tooth can be kept dry during placement. Ask what material is proposed and why.

Neurological conditions

If you have been diagnosed with multiple sclerosis, Alzheimer's disease, Parkinson's disease or another neurological condition, you are in a group the FDA named. The practical effect is simple: new fillings would be planned with non-mercury materials. The recommendation does not advise removing sound existing fillings, and it makes no claim that doing so would change the course of the condition. Tell the office the diagnosis, the treating physician's name and your medication list.

Impaired kidney function

The FDA includes impaired kidney function on its list of groups that may be more susceptible to mercury's effects. Again, the advice concerns new placements. Let the office know your diagnosis and the name of your nephrologist or primary physician. Your medical conditions and medications also shape how any dental treatment is planned, so the health history matters beyond the filling material itself; see why your dentist asks about medications.

Known sensitivity or allergy to mercury or other amalgam metals

A documented allergy to a filling component is one of the clearest reasons to choose a different material, and the FDA names it both as a reason to avoid new amalgam and gives documented hypersensitivity as its example of a reason a health care professional may consider removing an existing filling medically necessary.

Allergy or sensitivity: what "documented" usually means

A suspected sensitivity is evaluated rather than assumed. "Documented" usually means a physician or allergist has tested you, often with skin patch testing for metals, and recorded the result in your medical record. Oral signs that can prompt such an evaluation include changes in the lining of the mouth next to a filling. Those findings have other possible causes too, which is why the dentist examines first and then suggests you arrange testing through your physician if the picture fits. Ask the office how it approaches a suspected sensitivity; the testing itself is arranged through your medical providers. If a true allergy is confirmed, the FDA gives documented hypersensitivity as an example of a reason a dentist or physician may consider replacement medically necessary, and the replacement is then planned like any other restoration.

Existing fillings if you are in one of these groups

The FDA's position is the same for the higher-risk groups as for everyone else: leave a sound amalgam filling alone unless there is a medical or dental reason to intervene. Our guide on whether a sound silver filling should be removed covers the general question. Dental reasons for replacement are the usual ones: decay under or beside the filling, a crack in the filling or the tooth, a broken-down margin that traps plaque, or a filling that has fallen out; see cracked amalgam or decay underneath. The FDA's example of a medical reason is documented hypersensitivity to the amalgam material, confirmed through your medical providers.

If replacement is chosen for one of those reasons, the removal can be planned with the exposure-reduction steps described in replacing amalgam fillings: precautions and planning. For a pregnant or nursing patient, the timing of a non-urgent replacement is usually discussed with the obstetric provider rather than decided in the dental chair.

What this means at a mercury-free office

Loul Dental Studio lists mercury-free restorations among its services, so a new filling here is planned with tooth-colored material. For a patient in one of the FDA's named groups, that lines up with the agency's recommendation for new placements without any additional health claim attached. Tooth-colored materials have their own trade-offs: resin-based fillings generally require less healthy tooth to be removed and are matched to the tooth's color, but their durability may not reach that of amalgam in some large back-tooth fillings under heavy bite forces, and placement takes more time and depends on keeping the tooth dry. The guide on mercury-free dentistry in Santa Barbara explains how new and existing fillings are separate decisions.

The next step

If you belong to one of the groups above, the most useful thing you can do before an appointment is to update your health history: your diagnoses, your full medication list including supplements, whether you are pregnant, planning a pregnancy or nursing, any allergy testing you have had, and the names of the physicians involved in your care. Bring that information, or complete it on the health history form, and tell the team which group concerns you. You can request an appointment online; a request is not a confirmed appointment, and the team will follow up. If you have facial swelling with fever, trouble breathing or swallowing, or rapidly spreading swelling, that is an emergency for 911 or the nearest emergency department, not for the request form.