Should a sound silver filling be removed?

The short answer: a sound filling usually stays

If your silver filling is intact, its edges are sealed and your dentist finds no decay beneath it, the usual recommendation is to leave it alone. The U.S. Food and Drug Administration (FDA) does not recommend removing or replacing amalgam fillings that are in good condition unless it is medically necessary, for two reasons: taking a filling out removes healthy tooth structure along with it, and the drilling temporarily increases the mercury vapor you are exposed to. So for most sound fillings the answer is usually no.

The exceptions are clinical. Decay under the filling, a broken or cracked filling, a cracked tooth, edges that no longer seal, or sensitivity that does not settle can each make replacement the sensible choice. A considered personal preference, after the trade-offs have been explained, is also a legitimate reason. What an examination determines is which of these situations applies to the tooth in front of you.

What a silver filling actually is

"Silver filling" is the everyday name for dental amalgam. It is a mixture of liquid elemental mercury and a powdered alloy of silver, tin and copper; about half of the set material is mercury by weight. Once the filling hardens, the mercury is bound into the alloy, but a very small amount of mercury vapor is released over time, and more is released during the minutes when a filling is being placed or drilled out.

The FDA has reviewed the evidence on this exposure more than once. Its current position is that the majority of evidence suggests exposure to mercury from dental amalgam does not lead to negative health effects in the general population. At the same time, it does not describe the exposure as risk-free for everyone, which is where the 2020 recommendations come in.

The FDA's 2020 recommendations: two separate decisions

In September 2020 the FDA issued updated recommendations about amalgam for people who may be at greater risk from mercury vapor. It is easy to read those headlines as "take your fillings out." They say something narrower.

Who the recommendations cover

The FDA recommends that the following groups avoid getting new amalgam fillings whenever possible and appropriate, and that non-mercury materials such as composite resin or glass ionomer (both tooth-colored filling materials) be used instead when the dentist considers them suitable for the tooth:

• People who are pregnant, planning a pregnancy, or nursing, and their infants.
• Children, especially those younger than six.
• People with a pre-existing neurological condition.
• People with impaired kidney function.
• People with a known sensitivity or allergy to mercury or the other components of amalgam.

If you belong to one of these groups, tell the dentist before any new filling is planned. Questions about medications, pregnancy or a medical condition belong with both your dentist and your physician.

Why removal is a different question

The same FDA guidance is clear that it does not recommend removing intact fillings in good condition from people in these groups on that basis alone. The recommendations are about choosing a material for a new filling, when a tooth needs one anyway. Removal is a separate decision with its own trade-offs: the mercury vapor released while drilling out an old filling may be a larger exposure than the filling produces in everyday use, and the tooth loses structure each time it is re-prepared. Keeping the two decisions apart is one of the most useful things a patient can do with the FDA's guidance.

Clinical reasons a replacement may be discussed

An old amalgam filling is usually removed when the tooth, not the material, calls for it. The common reasons:

• Decay beneath or beside the filling. Decay can start silently at the edge of an old filling. It is usually found by probing and on X-rays, which show what the eye cannot see under a restoration. Early decay often causes no pain, so the finding often comes at a routine check-up (see Can you have a cavity without tooth pain?).
• A broken or cracked filling. A fracture through the filling leaves a gap that bacteria can enter.
• A cracked tooth. Large old fillings leave thinner walls of tooth around them, and a cusp can crack. The typical sign is a sharp pain on biting or on release, often with sensitivity to cold. Cracks may not show on an X-ray and are found with careful examination and biting tests.
• Edges that no longer seal. The edges of an old filling can wear or break down over many years. Worn edges without decay are often watched; edges that are leaking or trapping food may be replaced.
• Sensitivity that persists. A tooth that stays sensitive around an old filling needs a cause found before anything is replaced.
• A confirmed allergic reaction to the filling material. Allergic reactions to amalgam are rare, but when a dentist or physician has confirmed one, replacement may be discussed as a medical reason rather than a preference.

How much of the filling is removed, and whether the tooth then needs a filling, an onlay or a crown, depends on how much sound tooth remains once the old material and any decay are out. That is decided during the appointment, not before it. If you have rapidly spreading swelling of the face, jaw or neck, fever with facial swelling, or any difficulty breathing or swallowing, that is an emergency (see when emergency medical care comes first): call 911 or go to the nearest emergency department rather than waiting for a dental appointment.

Replacing a filling for appearance or preference

Some people simply do not want metal showing in a tooth, or prefer not to have mercury-containing material in their mouth, and that is a legitimate reason to ask about replacement. An honest conversation about it includes a few points that often get left out:

• Tooth-colored materials have their own failure patterns. The ADA notes that composite fillings may wear out sooner than amalgam fillings, and new decay around any filling is a common reason for replacement. Materials and techniques keep improving, but "white" does not automatically mean "longer lasting."
• Replacement removes more tooth. Every time a filling is drilled out, some healthy tooth goes with it, and the cavity gets larger. A tooth can be re-filled only so many times before a crown becomes the realistic option.
• Exposure rises briefly during placement and removal. If the concern driving the request is mercury exposure, it is worth knowing that removing a sound filling produces a short-term increase, not a decrease. In one small study that measured mercury in blood and urine after removal, plasma levels rose briefly in the first days, the rise was smaller when the teeth were isolated with a rubber dam (a thin protective sheet placed around the teeth) during the work, and urinary mercury fell meaningfully only over the following months. Ask what isolation and suction measures the office uses if you decide to proceed.
• Timing matters for some patients. If you are pregnant or nursing, elective removal of a sound filling is usually something to postpone and to discuss with your physician as well as your dentist.

None of this means a preference-based replacement is wrong. It means the decision should be made with the trade-offs on the table, one tooth at a time, and often spread over time rather than all at once.

What this practice does and does not claim

Loul Dental Studio lists mercury-free restorations among its services, meaning the practice offers restorations made without amalgam when a tooth needs a new filling or restoration; ask the office which material it would suggest for your tooth. That is a material choice for new work. It is not a claim about your health.

Specifically, the practice does not claim that removing amalgam fillings treats, cures, prevents or "detoxifies" any medical condition. The published evidence does not support such a claim. A small Norwegian study did report that patients who attributed health complaints to their fillings described fewer complaints five years after removal, but the study was small, participants knew what treatment they had received, and the outcomes were self-reported, so the removal itself cannot be separated from the effects of attention, follow-up and relief from worry. NIDCR-funded research in children, meanwhile, found no differences in kidney function or IQ test performance between children with amalgam fillings and children with other filling types. An association between how someone feels and when a filling came out is not evidence that the filling caused the symptom.

If anyone tells you that removing your fillings will fix a medical problem, that is a reason to ask for the evidence and to involve your physician. The guides on what biologic dentistry means and an evidence-based consultation checklist go further into the questions worth asking.

Using the decision aid

The decision table that accompanies this guide sorts the common situations into "usually keep and monitor" and "replacement may be discussed." It is a way to organize a conversation, not a diagnosis. Only an examination with X-rays can tell which row your tooth belongs in, and a dentist may reasonably move a tooth from one column to the other based on what is found.

The next step

Request an examination rather than a removal. Bring a list of your medications and any health conditions, mention pregnancy or plans for one, and say which fillings concern you and why. The dentist examines each filling, takes X-rays where they are due, and only then recommends keeping, watching or replacing it. You can request an appointment online (a request is not a confirmed appointment; the team follows up) or call the office during business hours.