Intrinsic Vs. Extrinsic Tooth Stains

Most people know what causes tooth stains. When you drink too much coffee or red wine, you might get a tooth stain! Forget to brush your teeth twice a day? You’re more likely to end up with a stain.

What you may not know is that there are actually two different types of staining that can occur!

Here at Dental House, we can help you care for all kinds of tooth discolouration and staining. What are the different types of staining—and how do we treat them? Read on to find out. 

What causes teeth to stain?

There are, broadly speaking, two different ways your teeth can be discoloured or stained—intrinsic stains and extrinsic stains.

Extrinsic stains are among the most common types of stains. These are stains that appear on the surface of the tooth—extrinsic stains are caused by food, smoking, and other factors.

Intrinsic stains, on the other hand, are inherent to the tooth—they can’t be removed in the same way as extrinsic stains. That might sound a little vague, but when you read all about intrinsic stains later in this article, you’ll get a much better idea of what we’re talking about.

We can treat both intrinsic and extrinsic stains—but they’re treated in different ways. Let’s start by talking about extrinsic stains, then work our way in!

What are extrinsic tooth stains?

Extrinsic tooth stains are stains that form on the surface of your teeth. These are the easiest stains for dentists to treat. 

What causes extrinsic tooth stains?

There are a variety of different substances that can cause extrinsic tooth stains, including:

  • Tobacco (smoked or chewed)
  • Certain foods (chocolate, tomato-based sauces, curries, etc.)
  • Certain drinks (coffee, tea, red wine, etc.)
  • Certain topical medications, including certain antiseptic mouthwashes

You should be on the lookout for any foods containing tannins. Tannins have been used for millennia to tan hides into leather, so it’s no surprise that foods containing tannins (like pomegranate) can stain your teeth.

While all of these substances can cause tooth stains, the biggest culprits are plaque and tartar. Bacteria will stain your plaque and tartar different colours—you may see yellows, greys, or even black tartar. Plaque also contributes to demineralization, a process that can cause white spots to form on your teeth.

Treating extrinsic stains

There are several techniques that dentists use to treat extrinsic stains. The first course of action is to clean your teeth. Plaque and tartar are two of the most common causes of discolouration, so scaling and planing performed by a dental hygienist can drastically reduce the appearance of staining.

Once plaque and tartar have been removed, your hygienist will use a high-powered electric brush and abrasive toothpaste to clean the surface of your teeth. You can think of this as a way of polishing your teeth—the gritty toothpaste will remove most extrinsic stains.

After your cleaning is complete, your dentist will check to see if you still have any stains that remain. Sometimes, your dental team won’t be able to remove these stains through scaling, planing, and polishing alone. In these cases, your dentist might propose one of several different bleach-based whitening techniques to eliminate the stains. 

What are intrinsic tooth stains?

Intrinsic tooth stains are any discolourations of the tooth that aren’t simple, surface-level staining. These stains cannot be removed through scaling, planing, polishing, and other mechanical means. This makes them more challenging to treat—but even intrinsic discolouration can be improved with the right techniques.

What causes intrinsic discolouration?

The causes of intrinsic discolouration are varied. They include:

  • Developmental and early childhood diseases, like enamel hypoplasia
  • Trauma to the teeth
  • Fluorosis, an excess of fluoride
  • Cavities
  • Tetracycline ingestion during tooth development

The biggest cause of intrinsic discolouration, however, is tooth wear. Your teeth are made up of layers of material. Underneath the enamel that we often associate with our “pearly whites” is dentin, a substance with a yellow colour. When your enamel wears away, the dentin below it becomes exposed, giving your teeth a yellow or brown colour. 

Treating intrinsic stains

Intrinsic stains can sometimes be treated through in-office whitening. Your dentist will first ensure that any extrinsic stains have been carefully cleaned before bleaching your teeth. 

Many intrinsic stains are difficult to treat, even with whitening. In these circumstances, other cosmetic treatments may be a better option. Veneers, for example, are an excellent way to treat intrinsic stains that don’t otherwise respond well to bleaching. 

How to distinguish between intrinsic and extrinsic stains

Talk to your Saskatoon dentist! You can guess at which stains are intrinsic and extrinsic—but there’s really no reason to, as both types of stain are best treated by dentists and dental hygienists.

For those who are really interested in guessing, however, there are a few methods you can use. One is to literally feel the surface of your tooth—you can sometimes feel extrinsic stains, especially if they’re plaque or tartar stains. Another is to look at colouration—extrinsic stains can be a variety of different colours, while intrinsic stains are commonly yellow or brown. 

Does teeth whitening work on intrinsic stains?

Teeth whitening can work on intrinsic stains—but it’s usually not the best option. Veneers, crowns or other cosmetic treatments are typically the best options. 

Will my teeth get stained again?

To be blunt? Almost definitely. Remember, your teeth can be stained by foods, medications, wear, cavities, and more. Whitening doesn’t make your teeth more resistant to staining. 

Veneers and other cosmetic treatments can hide intrinsic staining—but veneers themselves can develop extrinsic stains. That’s why it’s important to care for your teeth after whitening and other cosmetic treatments—staining can come back.