Pennington Dental

Yellow Teeth Cause

Why teeth lose their brightness — and what can be done

Tooth discolouration is one of the most common concerns patients raise with us at Pennington Dental. It affects people of all ages, and the causes are more varied than many patients realise. Understanding why your teeth have changed colour is the starting point for choosing the most effective treatment.

Extrinsic staining: stains on the surface

Extrinsic staining sits on or just beneath the surface of the enamel and is caused by the foods, drinks, and habits you are exposed to over time. Tea and coffee are the most common culprits in the UK, both are rich in tannins, which bond readily to the enamel surface. Red wine, dark fruit juices, cola, and curries all contribute. Smoking introduces tar and nicotine compounds that create particularly tenacious, brownish-yellow staining that is among the most difficult to shift.

Extrinsic staining responds well to professional whitening because the whitening gel can penetrate the enamel surface and break down the staining compounds. Hygienist appointments, professional cleaning with specialised tools, also remove a significant proportion of surface staining and are often a sensible first step before whitening.

Intrinsic discolouration: staining within the tooth

Intrinsic discolouration originates inside the tooth structure itself and is generally more challenging to address than surface staining. Common causes include:

Ageing: As we get older, the outer layer of enamel gradually thins through normal wear, revealing more of the dentine beneath. Dentine is naturally more yellow than enamel. This type of discolouration is progressive and structural — professional whitening can improve it meaningfully, but it will continue to develop over time.

Tetracycline antibiotics: Taken during tooth development in childhood, tetracycline antibiotics bind to the developing tooth structure and cause grey, orange or brown banding that is intrinsic to the dentine. This is one of the hardest types of discolouration to treat. Professional whitening can produce some improvement but it tends to take months of continuous whitening to see an effect. Some patients have to have porcelain veneers to achieve their desired result in severe cases.

Fluorosis: Excessive fluoride intake during tooth development causes white patches or, in more severe cases, brownish pitting on the enamel surface. Mild fluorosis may be improved with whitening or icon resin infiltration; more significant cases may respond better to composite bonding or veneers.

Trauma: A tooth that has been knocked can sometimes darken over time as the pulp (nerve tissue) inside is affected. This type of discolouration may require root canal treatment, internal bleaching, or in some cases a crown.

Which treatment is appropriate?

This depends on the cause and severity of your discolouration, which is precisely why a consultation with a dentist is the right starting point. For straightforward extrinsic or age-related staining, professional whitening is usually very effective. For intrinsic staining or structural concerns, the options may include whitening, composite bonding, or veneers — your dentist will advise on which is most appropriate and realistic for your specific situation.

At Pennington Dental, we offer free consultations for teeth whitening. Our protocol uses Boutique Whitening with a bespoke tray fabricated from a digital intraoral scan with no uncomfortable impressions. It includes a prescription desensitising toothpaste used for two weeks before and throughout the 4 to 6 week programme. The all-inclusive fee is £299, covering your scan, trays, gel, toothpaste, and both review appointments. Book your free consultation in Stratford-upon-Avon or Kenilworth today.

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