How long does a dental filling last?

Ask around and you will be given several different ranges, because the studies behind them measure different things in different populations: a filling “survives” in one study if it is still in the tooth, and in another only if it is still sealing perfectly. Patients also differ more than materials do — saliva, diet, grinding and cleaning habits vary enormously from one mouth to the next.

One finding survives all of that, and it is worth internalising. The strongest predictor of how long a filling lasts is how large it was to start with. A small one-surface filling has sound tooth around it for support; a big multi-surface rebuild is holding a weakened tooth together, and every chew works on the join. Size beats brand, every time.

Where the research allows a firmer figure, it points the same way as that table. On average across studies, the median service life of a composite filling in a back tooth is around eleven years, while amalgam fillings have typically lasted more than sixteen. The annual failure rates behind those medians — roughly 0.9–9.4 % for composite and 0.2–2.8 % for amalgam — show how wide the spread between study populations is.

Two caveats before you take those numbers to heart. Averages describe groups, not your tooth, and knowing the range says little about which end you will land on. And a filling does not expire like yoghurt: it either still seals and functions or it does not, and that is decided by examination, not by a date.

The size of the defect. The biggest single factor — and the one already fixed by the time the filling is placed.

Grinding and clenching. Bruxism (Bruxismus) multiplies the forces on a restoration and applies them for hours at night, when you have no protective reflexes. Grinders break fillings, chip cusps and wear down chewing surfaces. If you wake with a tight jaw or headaches at the temples, this is your topic — and a night guard (Knirscherschiene) is the answer.

Moisture at the wrong moment. Composite is glued, and the adhesive bond needs a dry surface. Saliva or blood reaching the prepared tooth in the minutes before placement weakens that bond, which is why isolation with a rubber dam (Kofferdam) or careful suction is worth the extra minutes.

Cleaning that stops at the margin. Decay at the edge of an existing filling is one of the commonest findings in adult dentistry. Brushing reaches the chewing surface; the space between the teeth, where most margins sit, needs floss or interdental brushes. This is the part of the lifespan genuinely in your hands.

Acid and a dry mouth. Sparkling water all day, citrus, juice, energy and sports drinks, plus reflux — all erode the tooth at the margin, and frequency does more damage than quantity. Saliva is the counterweight: it neutralises acid and returns minerals to the tooth, and many everyday medications reduce it. A dry mouth means your fillings work in worse conditions and need reviewing more often.

Position in the mouth. A filling at the neck of a tooth sits in the wettest, most awkward place there is; one on a molar’s chewing surface takes the greatest force. Smoking adds its own burden — staining, worse gum health, and recession that exposes the vulnerable root surface at the filling’s edge.

Some of this is our side of the table, some of it is yours.

Our side. Removing only decayed tissue. Keeping the tooth dry. Layering the composite in small increments so it shrinks less as it cures. Rebuilding a real contact point so food does not pack in. Checking the bite — a filling that sits high does not just hurt, it takes hammering it was never designed for. Polishing to a genuine shine, because rough composite collects plaque. Working under a microscope where the margin is hard to see.

Your side. Clean between your teeth once a day: this single habit protects more filling margins than any material choice. Use fluoride toothpaste, keep sugar and acid to mealtimes rather than grazing, and wear the night guard if you have one. And keep your check-ups — routine examinations are covered for statutory patients, and one visit per calendar year keeps your bonus booklet (Bonusheft) complete, which matters later for crowns and dentures. Professional cleaning (professionelle Zahnreinigung, PZR) is not part of standard care for most adults, though many funds contribute; ask yours. Fillings and caries treatment – service page (EN)

Not quite, and this is the part worth understanding before you agree to a routine swap.

Each time a filling is removed and remade, a little more healthy tooth goes with it. The cavity widens, the walls thin, and each successive restoration has less to hold on to — so the next one, on average, does not last as long as the one before. Repeat that often enough and a tooth that once needed a small filling ends up needing a crown. Dentists call this the restorative cycle.

Two practical consequences. First: an intact, well-sealing filling should be left alone whatever its age, and German dental associations do not regard age on its own as a reason for replacement. Second: where only one corner has failed, repairing that section instead of removing everything preserves substance and is a recognised approach. The best filling for a tooth’s future is often the one already there. Which signs genuinely mean replacement: When does a filling need to be replaced? (EN).

And what a replacement costs you. As a statutory patient, the new filling is covered exactly like the first. Since the EU amalgam ban in 2025, standard care (Regelversorgung) means a tooth-coloured filling in front teeth and back teeth alike, provided as a benefit in kind with nothing to pay at the desk. A difference arises only if you choose something beyond that standard — a laboratory-made inlay, say — under a written extra-cost agreement (Mehrkostenvereinbarung) signed before treatment: Does the statutory fund pay for fillings? (EN).

Rarely dramatic. The typical picture is a fine gap opening at the margin, bacteria getting underneath, and decay spreading in the softer dentine below — often with no symptoms until it is well established. Sometimes a corner chips, or the tooth cracks around a large old filling. Occasionally the whole thing comes out while you are eating something sticky, which is alarming but usually the least serious version.

That silence is why routine examinations and the occasional bitewing X-ray matter: they find margin failure and hidden decay while a small repair is still enough.

Teenagers and young adults. Fillings placed in childhood meet adult chewing forces and adult diets. Early adulthood is a sensible point for one thorough review rather than years of drift.

Older patients. Gums recede with time and expose root surfaces, which decay faster than enamel and sit right where many filling margins are. Add a dry mouth from medication and the picture changes: not worse teeth, but teeth in tougher conditions.

Pregnancy. Hormonal changes make gums more reactive and, for some, more prone to inflammation around filling margins. Careful cleaning matters more than usual, and treatment during pregnancy is possible where it is needed.

If you have moved to Germany recently. Nobody here has your history. Old X-rays, a summary from your previous dentist or even photographs help us judge whether a filling is five or fifteen years old, and that changes what we look for. All of this is far easier to discuss in a language you are fluent in — we work in English as standard, and also in German, Russian, Turkish, Ukrainian, Arabic, Kurdish and French. English-Speaking Dentist in NRW