Replacing Old Mercury (Amalgam) Fillings: What Actually Changes
Mercury-safe dentistry · 26 August 2026 · 5 min read
A mercury amalgam filling is worth replacing when it is failing — decayed underneath, cracking the tooth, or too large for its remaining walls to be safe. It is removed under rubber-dam isolation with high-volume suction, sectioned into pieces rather than ground out whole, and rebuilt in ceramic or BPA-free composite.
Why a filling gets replaced
Amalgam is roughly half mercury by weight, bound in an alloy, and a sound amalgam filling that is not failing can reasonably be left alone — removing any filling costs some tooth structure, amalgam included. The clinical reasons to replace one are the usual ones for any ageing restoration: decay underneath, a crack in the tooth, a fractured margin, or a filling so large the remaining tooth walls are at risk of breaking.
Wanting metal-free restorations for your own reasons is also a legitimate choice, separate from any of the above. We will discuss what each tooth actually needs either way.
The removal protocol
Cutting into old amalgam releases mercury vapour briefly, so removal is done under a rubber dam to isolate the tooth, with high-volume suction running throughout. The filling is sectioned into pieces and lifted out rather than ground away whole, which reduces the amount of material aerosolised during the appointment.
What replaces it
Once the old filling and any decay beneath it are out, the tooth is rebuilt in either a ceramic onlay or crown, designed and milled in the clinic and bonded the same visit, or a BPA-free composite filling. Which one depends on how much sound tooth structure is left once the amalgam is out — a small filling is usually replaced with composite; a tooth that has lost more structure is better served by a bonded ceramic restoration.
What we will not claim
We will not tell you that removing sound amalgam fillings treats an unrelated medical condition — there is no evidence for that, and it is worth being wary of anyone who says otherwise. The reasons above are the honest ones: a failing restoration, or your own informed preference.
Questions
Should I have my silver fillings removed?
Not automatically. A sound amalgam filling that is not failing can reasonably be left alone — removing any filling costs some tooth structure. The usual reasons to replace one are decay underneath, a crack in the tooth, a fractured margin, or a filling so large the remaining walls are at risk. Wanting metal-free restorations for your own reasons is also a legitimate choice.
Is amalgam removal itself safe?
Removal briefly releases mercury vapour, which is why it is done under rubber-dam isolation with high-volume suction and the old filling sectioned into pieces rather than ground out whole — this limits exposure during the appointment itself.
What replaces the old filling?
Ceramic, milled and bonded the same visit, or a BPA-free composite filling — chosen depending on how much sound tooth structure remains once the old filling is out.
Is this covered by Medisave?
No. Like most fillings, mercury-safe amalgam replacement is not Medisave-claimable. We confirm what applies in your written quotation.