couple with teeth whitening teeth

How to Improve Stained or Discoloured Teeth

Tooth discolouration is a natural process and happens to everyone over time. Below is a brief overview of the different types of tooth discolouration and what you can do to improve the appearance of your teeth.

Types of tooth discolouration

As we age, our teeth change colour and can be influenced by the foods we eat and our oral habits. This discolouration can be broken down into three broad categories: extrinsic, intrinsic and age-related.

Extrinsic Tooth Discolouration

Extrinsic tooth discolouration is caused when the outer layer of the tooth (the enamel) is stained. Causes of extrinsic staining include food and drink, things like red wine, coffee, soy and tomato sauce, or berries can all stain your teeth. Smoking and tobacco chewing also lead to extrinsic staining.

Intrinsic Tooth Discolouration

Intrinsic discolouration occurs when the inner tooth structure (the dentin) is darker than normal. This can be caused by tooth development issues such as excess fluoride or antibiotic use during pregnancy or early-life. Teeth that have been traumatised or undergone root canal therapy can also change colour and may appear darker or even turn black.

Age-Related Tooth Discolouration

As we age our enamel wears away and the underlying dentin becomes denser. Dentin is naturally yellow-brown in colour, so as the proportion of dentine becomes thicker the tooth becomes darker.

What can I do to improve the appearance of my teeth?

Good dental hygiene

A good oral hygiene routine consists of brushing at least twice a day for a minimum of 2 minutes with a soft toothbrush. As well, it is recommended to floss at least once a day, making sure to clean the line between tooth and gums and between the teeth.

Myth: Whitening toothpaste

Whitening toothpastes are generally not a good idea. The amount of bleaching agent in them is quite low, so the teeth themselves don’t change colour. They tend to be very abrasive, running the risk of damaging your gums and scratching any fillings or veneers you may have and making them more prone to extrinsic staining.

Tricks with staining foods

After you eat or drink anything other than water, we always recommend quickly rinsing your mouth out with water to remove residual food and liquid from your teeth. It is these ‘leftover’ particles that are the biggest contributors to extrinsic staining. If you are not able to rinse out with water afterwards, a good idea is to chew sugar-free gum instead.

Regular dental visits

During your 6-monthly dental check-up and clean, your dentist or oral health therapist will professionally clean your teeth. This may remove some tooth discolouration, although many stains are permanent unless the teeth are treated with a whitening (bleaching) gel.

teeth whitening before and after

What treatments can whiten teeth?

There are several ways to whiten teeth but the right treatment for you depends on the types of stains affecting your teeth and your desired outcome.

Teeth whitening at home

You can get over-the-counter whitening agents or a take-home whitening kit from your dentist. The differences between the two are the dentist take-home kit comes with a custom-made trays that tightly fit over your teeth. The tray that you will use for the treatment and the dentist take-home gel may be stronger than the over-the-counter version.

Your dentist will have to take impressions of your teeth to make these trays, so they fit snugly onto your teeth. The whitening gel is then applied in little pea-sized portions into the gap for every tooth and left in place for a period of time.

The take-home bleaching gels are not as strong as those applied by your dentist in-chair, meaning the process will take longer to achieve results. Most take-home whitening kits take between two to four weeks to whiten your teeth.

Teeth whitening in chair

In-chair whitening can take between 45 minutes and 1.5 hours. At the start of the Philips Zoom whitening treatment, your dentist will cover your lips and gums and will apply a high strength whitening gel to your exposed teeth. The whitening gel works together with LED heat lamp and breaks down your stains and discolouration.

In-chair whitening is broken down into 15 minutes cycles. Depending on the sensitivity of your teeth and the result that you would like to achieve, the number of cycles can vary between 2-4 cycles. 3 cycles are considered as the norm. While the gel and light are working, you can listen to music or watch TV.

If your tooth has darkened due to a trauma or after a root canal, teeth whitening of the enamel won’t change the colour of the tooth as the problem is deeper down in the dentin. You may need to consider internal (inside the tooth) bleaching or covering the tooth with a crown or veneer.


Some intrinsic stains that are caused by nerve or blood vessel damage of the inner part of the tooth can’t be fixed with teeth whitening. Veneers are a thin layer made of porcelain or composite resin (filling material) which can cover a stained tooth like an artificial fingernail would cover your real nail. The colour of your veneer can then match the colour of your surrounding teeth.

If you are looking for an instant white smile, start your free online consultation or give our team a call today on 07 5576 9333.