Dra. Cléo Salustiano In this article
SummaryWhich signs show a filling needs to be replaced?Do I need to replace my amalgam fillings?FAQRead nextWhen to replace an old filling (and when you don't need to)
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Quick summary of this article+
An old filling needs replacing when there's decay underneath or at the edge, a fracture, leakage, persistent sensitivity, food always getting stuck in the same spot or inflamed gums next to it. An intact, well-sealed filling doesn't need to be removed just because it's old. A dark line may just be staining, which comes off with polishing, or leakage, which calls for replacement; an exam and X-ray tell them apart. Intact amalgam doesn't need replacing just because of the material; replacing it for appearance is the patient's informed decision. Today, composite resin and indirect ceramic or resin restorations are used. Regular checkups allow early repairs. In Mooca, Dr. Cléo Salustiano (CRO-SP 170844) sees patients every day, 8 a.m. to 10 p.m.
An old filling needs to be replaced when there's decay underneath it or at its edge, a fracture, leakage, persistent sensitivity, wear that has left the tooth unprotected, or when it gets in the way of keeping the gums clean. An intact, well-sealed filling with no signs of trouble doesn't need replacing just because it's old or made of a material more common in the past, such as amalgam (silver fillings). The decision depends on the exam, not on the filling's age.
In clinical practice, many patients come in with two opposite questions: 'my fillings are twenty years old, do I need to replace them all?' and 'it's never hurt, so it must be fine.' Neither is a rule. Old fillings can last a long time, and decay under a filling can advance without pain. What settles the question is an exam with good lighting, instruments and, often, an X-ray.
Dr. Cléo Salustiano (CRO-SP 170844), a dentist in Mooca, explains below the signs that a filling needs replacing, what to do about amalgam and which materials are commonly used today.
This article comes from Dr. Cléo Salustiano's dental office in Mooca, São Paulo (care in English, Portuguese and Spanish). See the general dentistry page to learn how the treatment is done here and book your assessment.
Which signs show a filling needs to be replaced?
The signs that a filling needs replacing are decay around or under it, a fracture of the filling or the tooth, leakage at the edge, sensitivity or pain that doesn't go away, food that always gets stuck in the same spot and gums that bleed or become inflamed next to the filling. You can notice some of these signs at home; others only show up in an exam and on an X-ray.
A dark line at the edge of a filling may just be surface staining, which comes off with polishing, or it may be leakage: a microscopic gap between the material and the tooth where bacteria get in. Over time, leakage can lead to secondary decay, which advances under the filling. Telling the two apart is part of the exam.
Fractures are another common reason. Large fillings, especially in back teeth, take the force of chewing and can crack or chip, sometimes taking part of the tooth with them. Teeth with very large fillings or root canal treatment are more fragile, and replacing the filling with a restoration that protects the whole tooth is often the safer option.
Sensitivity to cold, sweets or biting, when it shows up in a filled tooth and doesn't go away, may indicate leakage, decay, a crack or a filling that sits too high in the bite. Food that always gets stuck in the same spot is usually linked to a poor contact between teeth, which collects plaque and inflames the gums. In both cases, it's worth getting it checked before the problem grows.
There are also cosmetic reasons: dark or stained fillings on front teeth or in visible areas of the smile. Replacing a filling for appearance is the patient's decision, made after understanding the pros and cons, because every replacement removes a bit of tooth structure. On front teeth, good-quality, well-polished composite usually blends with the natural teeth.
| What's happening | What it usually indicates | Most common approach |
|---|---|---|
| Intact filling, no symptoms, normal X-ray | Filling in good condition | Keep and monitor at checkups |
| Dark line on the surface only | Surface staining | Polishing or a small repair |
| Dark line with a gap, or decay on the X-ray | Leakage or secondary decay | Replace the filling |
| Chipped filling or cracked tooth | Fracture | Repair, replacement or a restoration that protects the tooth |
| Food always getting stuck in the same spot | Poor contact between teeth | Adjust or replace the filling |
| Intact amalgam, no complaints | No clinical need to replace | Keep, unless an informed cosmetic choice is made |
Do I need to replace my amalgam fillings?
You don't need to replace an amalgam filling just because it's amalgam. If it's intact, well sealed and free of decay, the most common advice is to keep it and monitor it, because removing material in good condition always takes away some tooth and puts the patient through a procedure with no clinical need. Replacement is recommended when there's a fracture, leakage or decay, or when the patient chooses to replace it for appearance, after talking it over with the dentist.
Amalgam use has been declining worldwide due to international agreements to reduce mercury use, and today most new fillings are made with composite resin or ceramic materials. That doesn't make old fillings an immediate risk. When replacement is done, the dentist takes precautions to reduce exposure during removal, such as isolation and suction.
The most widely used materials today are composite resin, applied directly to the tooth and matched to its color, and indirect restorations such as inlays, onlays and crowns in ceramic or resin, used when the tooth has lost a lot of structure and needs more protection. The choice depends on the size of the filling, the tooth's position, the bite and habits such as teeth grinding (bruxism).
To help fillings last longer, the usual care applies: brushing with fluoride toothpaste, flossing every day, cutting down on sugar between meals, a night guard if you grind your teeth and regular checkups, where small flaws are polished or repaired before they turn into decay or a fracture. Repairing a filling, instead of replacing it entirely, is sometimes possible.
In Mooca, Dr. Cléo Salustiano assesses old fillings with an exam and X-rays and explains, tooth by tooth, what can be kept, repaired or replaced. No dentist can guarantee how long a filling will last; what follow-up does is catch early what needs attention.
Does an old filling need to be replaced?
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Only if there's a reason: decay underneath or at the edge, a fracture, leakage, sensitivity that doesn't go away, food always getting stuck in the same spot or inflamed gums next to it. An intact, well-sealed filling can be kept for many years, with monitoring at checkups.
How long does a filling last?
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There's no fixed timeframe. Longevity depends on the filling's size, the material, the tooth's position, the bite, teeth grinding, hygiene and diet. Some last decades; others need repair sooner. Regular follow-up is what tells you when to act.
Should I replace my amalgam fillings?
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There's no need to replace amalgam just because of the material when it's intact and decay-free. Replacement is recommended when there's a fracture, leakage or decay, or as the patient's cosmetic choice after understanding the pros and cons. Every replacement removes a bit of tooth structure.
Is a filling with a dark edge a cavity?
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Not always. It may be surface staining, which comes off with polishing, or leakage between the material and the tooth, which can lead to secondary decay. An exam with good lighting, instruments and, often, an X-ray shows which it is and whether replacement is needed.
Can there be decay under a filling without pain?
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Yes. Secondary decay often advances painlessly for quite a while, especially under large fillings. That's why checkups with periodic X-rays matter even if you don't feel anything. When pain appears, the decay is often already deeper.
Filled tooth sensitive to cold: what could it be?
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It could be leakage, decay at the edge, a crack in the tooth, a recent filling still settling in or a filling that sits too high in the bite. If the sensitivity doesn't fade within a few days or gets worse, it's worth getting it checked, because some of these causes can lead to nerve inflammation.
Can I replace a dark filling for appearance?
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Yes, as an informed decision. Dark or stained fillings in visible areas can be replaced with tooth-colored composite. The dentist explains that every replacement removes a bit of structure and checks whether repair or polishing would solve it before recommending full replacement.
What material is used for fillings today?
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The most common is composite resin, applied directly to the tooth and matched to its color. When the tooth has lost a lot of structure, indirect restorations such as inlays, onlays and crowns in ceramic or resin may be recommended, as they protect the tooth better. The choice depends on the case.
Can a filling be fixed without replacing all of it?
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Sometimes, yes. Small chips, flawed edges or worn spots can be repaired by adding material, preserving the rest of the filling and the tooth. Repair is considered when the filling is well sealed overall and there's no decay underneath.
Is food getting stuck between teeth related to a filling?
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Often. A poor contact between the filling and the neighboring tooth leaves room for food to get in, which inflames the gums and encourages decay. Adjusting or redoing the filling usually solves it. It can also be gum disease, which an exam can distinguish.
Does replacing a filling hurt?
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In general, it's done under local anesthesia, so it doesn't hurt during the procedure. There may be mild sensitivity for a few days afterward, especially with deep fillings, which tends to fade. If the pain is strong or increases, let your dentist know.
How often should fillings be checked?
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At your checkups, which for most people happen every six months to a year, depending on cavity and gum risk. Periodic X-rays help show what the clinical exam can't. Your dentist sets the interval that suits you.
Where can I get old fillings assessed in Mooca?
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In Mooca, Dr. Cléo Salustiano (CRO-SP 170844) assesses old fillings with an exam and X-rays and explains what to keep, repair or replace. The office is at Rua Hipódromo, 1141, near Bresser-Mooca station (Metro Line 3-Red), open Monday to Sunday, 8 a.m. to 10 p.m., with care in Portuguese, English and Spanish, via WhatsApp (11) 97409-7834.
