What causes yellow teeth, grey teeth, see-through teeth, or a smile that’s simply darker than it used to be? Find out causes behind discolouration.
Dark or yellow teeth aren't always a sign of an oral health problem, and most teeth aren’t perfectly white on their own.
But if you have concerns or questions about the way your teeth look, it can help to understand any potential stains or discolouration as well as options for addressing them. A dentist may be able to help you address concerns like tooth stains, discoloured teeth or teeth that look see-through.
What causes teeth stains?
Not all teeth are naturally white. Plus, teeth tend to naturally darken as we age. The outer layer (enamel) may even start to slowly wear away. But teeth can darken or yellow for other reasons too, including:
- pigments left behind by strong-coloured food and drink (e.g. tea, coffee, red wine, soft drinks, berries and sauces)
- plaque build-up on the teeth
- tobacco and nicotine stains from smoking
- injury or trauma to the tooth
- erosion that wears down the tooth’s enamel or dentin
- a side-effect of certain medical conditions or medications.
Types of tooth discolouration
Staining happens when substances like coffee or wine stain the outer layer (enamel) of your tooth. This may cause them to look more yellow, grey or brown (or simply darker).
A dentist may be able to help you address these sorts of stains with a professional clean before looking into whether you need to use certain teeth whitening procedures.
Other types of tooth discolouration aren’t exactly stains. This is particularly true with “intrinsic discolouration,” where the inner tooth structure darkens or yellows. Sometimes this can happen for reasons that have nothing to do with your coffee or wine intake.
Teeth that have always looked darker or grey
If your teeth have always looked grey or dark since you were young, this might be a sign of intrinsic discolouration — that is, the darkening of your inner tooth structure (dentin). This can happen if you were exposed too early to too much fluoride, or if you or your mother used certain antibiotics at a young age, or when pregnant with you.
Teeth bleaching may not be able to change this sort of discolouration, since these procedures tend to only lift or lighten stains from the outer layer of your tooth, not the inner layers.
Teeth that look see-through
If your teeth look transparent, this might affect your smile’s brightness even though there aren’t stains on the tooth’s surface.
Transparent teeth may be a sign of tooth erosion, and teeth whitening isn’t always the right option if you’re trying to change this. You may need to consider a procedure like veneers, although a dental professional can advise you on causes and possible treatments.
Brown or dark spots or patches on teeth
Dark spots on teeth may be stains, but sometimes they can be a sign of tooth decay. A professional will need to examine your teeth to understand whether this discolouration is a sign of a dental health problem or a stain on the tooth’s surface.
Solutions for stains and discoloration
Depending on the type of discolouration and your own dental health factors, there are a variety of options a dentist might recommend.
When you visit your dentist for your regular check-up, they can also professionally clean, scale and polish your teeth. This can remove some external discolouration from plaque, but it can't lift deeper stains like those left by food and drink.
Professional teeth whitening or bleaching is a cosmetic treatment offered by dentists, and there are different variations like in-chair or take-home. Read more about professional teeth whitening.
Teeth bleaching treatments might brighten the look of your smile and help in lifting the shade of your enamel. However, they can't whiten teeth with internal discolouration from injuries or medication side-effects. They also don't work on fillings or crowns.
There are over-the-counter teeth whitening products, but it’s still a good idea to speak to a dentist even if you aren’t undergoing professional teeth whitening. An over-the-counter product may not be effective (or might even be counterproductive) if it’s not appropriate for the type of discolouration you’re trying to correct. A dental professional is usually in the best position to help you understand any discolouration and whether there’s an underlying health problem that needs treatment first.
Dentists can bond dental veneers to the front of teeth to change their appearance. Veneers can cover up most types of stains and discolouration, but the procedure usually involves removing part of the teeth before placing the veneers — it’s important to consult with a dentist and be sure that veneers are right for you.
Also, be aware that veneers can only change your teeth’s appearance. If a dental health problem is causing your discolouration, a dentist will need to help you address it before you get veneers.
Replacing crowns and fillings
How to avoid teeth stains
Teeth stains and discolouration can't always be avoided but knowing what causes them could help keep your teeth looking brighter for longer.
Taking good care of your teeth and gums can prevent plaque from forming and help to keep your teeth healthy. Dentists recommend:
- brushing your teeth twice a day for 2 minutes
- using fluoride toothpaste to help keep your enamel strong
- flossing between your teeth every day
- only using mouthwash or whitening toothpastes recommended by your dentist.
Food and drink stains
The best way to lower your chance of tooth stains is to avoid food and drink with strong pigments. If you don't want to sacrifice wine, coffee or other favourite beverages, you could reduce their effects on your teeth by:
- drinking through a straw to reduce contact with your front teeth
- rinsing your mouth with water to prevent stains from forming
- drinking tap water containing fluoride to help protect your teeth.
Talk to a professional
A dentist can help you understand your options, and regular check-ups may help them spot signs of a problem.
Find a dental clinic near you. The Dental Care Network listing will tell you if they offer possible discolouration solutions like teeth whitening, crowns or veneers.