Tooth discolouration is a common thing for many of us, and each of its many causal factors gives its own unique shade to our smiles. Whether it’s a subtle hint of yellow or a darker shade of black, the colours of tooth stains provide valuable insights into our oral health and daily habits.

The rainbow of tooth stains
Black: Tooth stains appearing black may signal the presence of iron deposits, or be caused by certain medications, bacterial growth within the tooth or materials used during root canal procedures. These factors can lead to dark pigmentation, altering the natural colour of the tooth.
Blue / Blue-Brown / Blue-Grey: These rare hues may result from bacterial activity or certain medications influencing tooth development. Conditions like dentinogenesis imperfecta, a genetic disorder, can lead to abnormal tooth development, resulting in bluish or opalescent hues.
Brown / Brown-Black / Brown-Grey / Golden Brown: Brown stains are the most common type of tooth discolouration and can originate from both external and internal factors. External factors such as consuming staining beverages like coffee or habits like cigarette smoking can contribute to brown discolouration. Meanwhile, intrinsic causes such as the use of tetracycline antibiotics during tooth development or excessive fluoride intake can also result in varying shades of brown discolouration.
Green / Green-Blue: Green stains typically indicate bacterial colonisation on the tooth surface, especially in individuals with poor oral hygiene practices. Additionally, certain medications or underlying medical conditions like hyperbilirubinemia, which causes an excess of bilirubin in the blood, can contribute to greenish discolouration of the teeth.
Grey / Dark Grey: The presence of grey or dark grey stains on teeth can be attributed to factors such as the presence of dental amalgam fillings, exposure to certain metals or the use of endodontic materials during dental procedures. Trauma to the tooth or conditions like pulp necrosis, where the tooth pulp becomes non-vital, can also lead to greyish discolouration.
Orange / Orange-Red: While less common, orange stains on teeth may result from bacterial growth on the tooth surface or the use of specific types of root canal cement. These stains often indicate localised areas of bacterial activity or dental material interactions.
Pink: Tooth discolouration with a pinkish hue may occur due to various factors, including trauma to the tooth, internal resorption where the tooth structure breaks down internally or the presence of certain materials used during endodontic procedures. In rare cases, systemic conditions like leprosy can manifest as a reddish discolouration of the teeth.
Red / Red-Purple / Red-Brown: These colours are typically associated with rare medical conditions such as porphyria, a group of disorders characterised by abnormal production of porphyrins or lepromatous leprosy. These conditions can cause significant changes in tooth colour, emphasising the importance of a thorough evaluation by a dental professional.
Yellow / Yellow-Green / Yellow-Brown: Yellowing of teeth can occur due to a variety of reasons, including enamel defects, trauma to the tooth, certain medications or lifestyle habits such as smoking or consuming certain foods and beverages. The build-up of stains and pigments on the tooth surface can lead to yellowish or yellow-brown discolouration, while underlying medical conditions or systemic factors may contribute to yellow-green hues.

How to address tooth stains
Diagnosis and treatment
While decoding the colours of tooth stains offers valuable insights, it’s essential to seek professional guidance from a dentist for accurate diagnosis and personalised treatment. A dental professional can assess the underlying causes and severity of discolouration, providing recommendations tailored to individual needs.
Treatment options may include:
- Professional cleaning to remove surface stains,
- Whitening procedures, such as in-chair and take-home kits, to brighten discoloured teeth, or
- Cosmetic solutions like veneers or crowns for more severe cases of discolouration.
Preventive care
Prevention is essential for maintaining optimal oral health and avoiding tooth discolouration.
Adopting good oral hygiene practices is key:
- Brush teeth twice daily with fluoride toothpaste.
- Floss regularly to remove plaque and prevent surface stains.
- Use mouthwash for additional oral hygiene.

Minimise exposure to factors that can cause staining:
- Limit your consumption of staining foods and beverages such as coffee, tea, red wine and alcohol.
- Avoid smoking.
Attend regular dental check-ups and cleanings, ideally every 6 months:
- Dentists can monitor oral health and detect early signs of discolouration and their underlying causes.
- Receive personalised preventive care and guidance tailored to your needs.
Understanding tooth discolouration for better oral health
Tooth stains aren’t just about looks—they can tell detailed and insightful stories about our oral health and habits. Understanding why our teeth change colour helps us make smart choices for better oral health. Taking care of our smiles means staying informed and proactive. If you’re experiencing discolouration, don’t hesitate to talk to your dentist. They’ll be able to give you some practical advice and help you keep your smile healthy and bright.