Stained or discoloured teeth are one of the most common cosmetic concerns we see at our Pymble practice, and one of the most satisfying to fix. The right treatment depends almost entirely on what is causing the discolouration, which is why a proper assessment always comes before any whitening discussion. At Dentist Pymble, we treat discoloured teeth for patients across the Ku-ring-gai region, and the conversations we have are almost always about whether to whiten, mask, or both. This page covers what causes stains, how to tell them apart, and the right treatment for each type.

What causes stained or discoloured teeth?

The list is long. The everyday causes are the foods and drinks we consume — coffee, tea, red wine, curry, soy sauce, and dark berries all deposit chromogens (pigment molecules) on the enamel that build up over time. Tobacco is another big one, both smoking and smokeless. Poor brushing technique lets the staining compounds stick, and some people’s saliva composition makes them more prone to stain pickup than others.

Beyond the everyday, there are medical causes. Tetracycline antibiotics taken during tooth development cause intrinsic grey or brown staining that runs through the tooth rather than sitting on top. Fluorosis (excess fluoride during development) causes white spots or brown discolouration. Trauma that kills the nerve turns a tooth dark grey or brown from the inside. And ageing itself causes the dentine underneath the enamel to yellow and show through as the enamel thins.

Extrinsic vs intrinsic tooth stains

The distinction matters because it drives the treatment. Extrinsic stains sit on the surface of the enamel. They are the coffee, tea, wine, and tobacco stains. They respond very well to a professional scale and clean, and they whiten predictably with professional whitening products. Most of the everyday discolouration people notice is extrinsic.

Intrinsic stains are within the tooth structure — they are part of the dentine or have penetrated into the enamel itself. Tetracycline staining, fluorosis, trauma-related discolouration, and age-related yellowing are all intrinsic. Intrinsic stains do not respond well to whitening because the peroxide cannot reach the pigment molecules inside the tooth. The treatment for intrinsic staining is to mask it, not bleach it — usually with veneers or crowns.

Professional whitening vs at-home kits

Professional whitening uses higher concentrations of hydrogen peroxide or carbamide peroxide than over-the-counter kits, with proper isolation of the gums and soft tissues to prevent burns. The result is faster, more even, and more predictable. In-chair whitening at our Pymble practice typically lightens teeth by 4-8 shades in a single 60-90 minute appointment. Take-home kits from a dentist (custom trays plus professional-strength gel) take 1-2 weeks of daily wear but produce comparable results over time.

Over-the-counter whitening strips, gels, and toothpastes from the chemist use much lower concentrations of active ingredient. They can produce modest improvements, particularly for mild extrinsic staining, but the results are slower, less dramatic, and less even. They are also more likely to cause sensitivity or gum irritation when used without professional supervision. For meaningful, predictable whitening, professional is the way to go.

When staining doesn’t whiten — veneers and crowns

If the discolouration is intrinsic, the answer is to mask it rather than bleach it. Porcelain veneers are thin shells of ceramic bonded to the front of the teeth, and they can be made in any shade. They are the gold standard for tetracycline staining, fluorosis, and age-related discolouration that does not respond to whitening. Results last 10-15 years with good care.

Composite veneers are a more affordable alternative — resin layered directly onto the tooth in a single appointment. They are not as durable or as stain-resistant as porcelain, but they are reversible, more affordable, and can be repaired easily. For a single dark tooth (often a previously traumatised or root-canaled tooth), a crown is often the most predictable option.

How much does teeth whitening cost in Pymble?

In-chair whitening and take-home kits from our teeth whitening service sit at different price points. Veneers and crowns are a separate investment, depending on the material and the number of teeth involved. We will always provide a written quote after the assessment, run a health-fund check on the day, and talk through the options with you before any treatment starts.

How long do whitening results last?

It depends on the cause of the original staining, the type of whitening, and your habits afterwards. In-chair whitening results typically last 1-3 years with good maintenance — brushing, flossing, occasional top-up gels, and avoiding the worst offenders (coffee, red wine, tobacco) or rinsing with water after them. Take-home kit results can last 2-4 years with proper care. Veneers and crowns do not change colour, but the teeth around them can, so maintenance is still important.

If you live in Pymble, Gordon, Turramurra, Wahroonga or anywhere else in the Ku-ring-gai area and you want to know whether your discolouration will whiten or whether veneers are the better answer, call our practice. We see neighbouring Gordon patients and other nearby residents, and the first conversation is always a free one.

Frequently asked questions

Will whitening work on tetracycline staining? Usually not, no. Tetracycline staining is intrinsic, which means the pigment is within the tooth rather than on the surface. Whitening cannot reach it. The treatment for tetracycline staining is usually veneers or crowns.

Is professional whitening safe? Yes, when done by a trained dentist. The gums and soft tissues are protected with a barrier, the whitening gel is applied at the right concentration for the right time, and the result is monitored. Sensitivity during or after treatment is the most common side effect, and it is usually temporary.

How white will my teeth get? It depends on the cause of the original discolouration, the type of staining, and the natural shade of your teeth. In-chair whitening typically lightens by 4-8 shades. The result is usually a few shades lighter than the natural whiteness of your eye teeth, which are typically the brightest teeth in your mouth.

Can I whiten a single dark tooth? Sometimes. If the tooth has been root-canaled and has darkened from the inside, internal bleaching (walking bleach) can be very effective. If that does not work, a veneer or a crown is the predictable answer.

Does whitening damage enamel? No. Professional whitening, when done correctly, does not damage enamel. The active ingredient penetrates the enamel to reach the pigment molecules in the dentine underneath, and the enamel itself is left intact.