The useful question is why yours have got yellower, because there are several different reasons, they look slightly different from each other, and each one has a different fix. Some come off in a single hygiene appointment. Some need whitening. One or two need something else entirely. Here is how we tell them apart in Cheltenham, and what we do about each.
Stains that sit on the surface
Tea, coffee, red wine, curry, tobacco and the mineral scale that builds up at the gum line all leave their mark on the outside of the enamel. Dentists call this extrinsic staining. It tends to be brownish rather than yellow, gathers between the teeth and along the gum edge, and is often worse on the inside of the lower front teeth where the tongue cannot reach.
The good news is that it is not part of the tooth. A hygiene appointment removes the tartar it clings to and polishes the surface, and for heavier or more stubborn staining we use air polishing, a fine jet of water, air and powder that lifts discolouration from the pits and edges a polishing cup cannot get into. Patients who come in for a clean before a whitening course are regularly surprised at how much lighter their teeth look before any gel has gone near them. Our hygiene appointments start at £82, and an air polish with a full hygiene clean is £138, both listed on our fees page.
Yellowing from inside the tooth
The second kind of discolouration lives inside the enamel and dentine, and no amount of polishing reaches it. The most common cause is simply time. Enamel thins a fraction with every decade of chewing and brushing, and dentine darkens as it ages, so the yellow underneath shows through more clearly at fifty than it did at twenty. Years of tea and coffee also soak pigment into the enamel itself, not just onto its surface.
This is the discolouration that whitening is designed for. Peroxide gel in a custom tray passes into the tooth and breaks the pigments down, lightening the dentine as well as the enamel. It is the only method that changes the colour of the tooth rather than the colour of what is sitting on it. Our guide to teeth whitening in Cheltenham explains how the trays work, what it costs and what to expect.
The odd one out: a single dark tooth
Sometimes it is not all the teeth but one. A front tooth that has turned grey or brownish on its own is usually a tooth whose nerve has died, often after a knock years earlier that seemed like nothing at the time. Bike accidents at ten, rugby at fifteen, a door at thirty. The tooth stops receiving blood, the tissue inside breaks down and the colour changes from within. Standard whitening lightens the neighbours and leaves it behind. It needs assessment first, sometimes root canal treatment, and then a targeted approach to the colour.
Marks you were born with, or grew up with
White flecks or brown patches that have been there since childhood are usually enamel that formed unevenly, either through a childhood illness, a high fluoride intake while the adult teeth were developing, or in some cases a course of tetracycline antibiotics. Tetracycline staining in particular shows as grey or brown bands across the teeth and is notoriously slow to whiten. These cases are where we are honest early. Whitening may help a little, but composite bonding or veneers are often the treatments that actually deliver the smile the patient is picturing.
Yellow that is not yellow at all
A few things look like discolouration and are not. Old white fillings that have darkened at the edges. A crown made years ago to match teeth that have since changed shade. Enamel worn thin by acid from fizzy drinks or reflux, which does not stain but lets more dentine show. Each of these is handled differently, and none of them respond to whitening gel, which is one of the reasons we examine before we prescribe.
How to slow it down
You cannot stop teeth ageing, but you can slow the staining. Drink tea and coffee rather than sip them over an hour. Rinse with water after red wine or curry. If you smoke, stopping does more for the colour of your teeth than any product can. Brush twice a day with a fluoride toothpaste, use interdental brushes or floss where the stain gathers, and see the hygienist regularly so the build-up never gets a chance to set. Whitening toothpastes help keep a clean surface clean, but they will not lighten dentine and the harsher ones wear enamel.
Frequently asked questions
Can yellow teeth become white again?
Does a hygiene clean whiten teeth?
Are yellow teeth a sign of poor hygiene?
Written by Dr Jakub Wojcicki,
Dentist at Oriel Villas Dental Surgery
(GDC No. 84982)