Tooth discoloration causes can be extrinsic and intrinsic. Extrinsic stains affect the tooth surface and can be caused by smoking, consuming staining foods or beverages, certain medications, or poor oral hygiene. Preventing stains caused by external factors can be achieved more easily, and stains can typically be removed through professional cleaning. Intrinsic stains, on the other hand, affect the tooth’s internal structure and are more difficult to address as they are more deep seated. It’s important to understand the causes of tooth discoloration to determine the most appropriate treatment.
Tooth Discoloration Causes
There are several causes of tooth discoloration, including:
- Caries or tooth decay: When bacteria break down tooth enamel, it can lead to discoloration.
- Congenital malformation in tooth development: Conditions such as molar incisor hypomineralisation (MIH); enamel hypoplasia; amelogenesis or dentinogenesis imperfecta can cause teeth to develop with natural intrinsic discoloration.
- Excessive fluoride intake during tooth development can also lead to fluorosis, a form of discoloration.
- Drugs: Certain medications, such as tetracyclines, can cause tooth discoloration.
- Dead or non-vital teeth: Teeth that have lost their nerve supply due to decay or trauma may become discoloured.
- Ageing: As we age, the outer layer of enamel on our teeth naturally thins, which can reveal the yellower dentin underneath.
- Decalcification or white spot lesions observed after completion of orthodontic treatment
Dental Care in Singapore: Treatment Options for Tooth Discoloration
Once the cause of tooth discoloration is determined, there are a few treatment options available:
- Teeth whitening: This is the most common method for reducing or removing intrinsic stains. It involves using bleaching agents, such as hydrogen peroxide or carbamide peroxide, to lighten the colour of the teeth.
- Veneers: These are thin, custom-made shells placed over the front of the teeth to improve their appearance.
Teeth Whitening Procedures
There are two main types of teeth whitening procedures:
Chair-side bleaching
Chair-side bleaching involves the application of hydrogen peroxide of varying concentrations to the external surface of the teeth followed by its activation by either a heat or light source.
The whole procedure takes place on the dentist’s chair. Each treatment appointment can take up to 1.5 hours and it may take 2-3 appointments to achieve the desired outcome. A discernible difference should be observed immediately after the appointment and the need for a second or third follow-up bleaching appointment depends on the patient’s expectations.
Slight relapse is a common occurrence about 6 to 12 months after the initial bleaching although it is not usual for the colour of the teeth to revert to the pre-treatment colour.
The management of such relapses may involve the use of either a home-use touch-up kit or in-clinic retreatment. Another common concern of bleaching is post-operative sensitivity and this tends to be more often for chair-side bleaching compared to the home bleaching kit.
ICON resin infiltration therapy
There are patients with very well demarcated blotches/patches (usually brown or opaque white) commonly observed after completion of orthodontic treatment around where the brackets were previously attached. These discolouration is caused by decalcification of the enamel as a result of poor oral hygiene and caries attack during orthodontic treatment. These ‘white spot’ lesions can be quite unsightly and cannot be cleaned away or corrected by teeth whitening alone. Another option now available to patients is to seal these decalcified areas with ICON resin infiltration therapy after bleaching for a more even and superior aesthetic outcome.
Home bleaching
Home bleaching involves the daily placement of carbamide peroxide gel into a custom-fitted tray over the upper and lower teeth.
As the name suggests, it is carried out by the patient in the comfort of his own home and at their convenience – therefore it is less expensive as less clinical chairside time is utilised. Patients are usually advised to wear the gel-loaded custom tray for 3-4 hours a day (preferably overnight) for 3-4 weeks for the colour to stabilise. As the bleaching reaction is oxidative, more frequent conscientious applications will result in better and faster results.
The other advantage of home bleaching is that this method is better able to achieve homogeneity in colour if certain teeth need to be lightened more than others. There are also less complaints of post-operative sensitivity as home bleaching is a more gradual process.
The additional use of a fluoride gel can also greatly alleviate sensitivity during the bleaching process. Technically, home bleaching can achieve the same results as chair-side bleaching if patient compliance is good and time is not a critical factor.
Safety Considerations
When used appropriately, teeth whitening procedures are safe and do not harm the underlying teeth or gums. In fact, there is no evidence that the clinical use of hydrogen and carbamide peroxide over the last 75 years to whiten teeth has led to any harmful effects to the underlying teeth provided the chemicals are used appropriately. The surrounding gums should be adequately protected from the bleaching agent although minor ulceration or irritation may occur during the initial treatment.
Therefore it is important to use these bleaching kits under the supervision of a dentist.
Tooth Discoloration Causes: Preventing Stains
While it may not be possible to entirely prevent all types of tooth discoloration causes, there are steps you can take to minimise extrinsic stains. Here are some tips in preventing stains:
- Practise good oral hygiene: Brush your teeth twice a day, floss daily, and use mouthwash to remove plaque and surface stains.
- Limit staining foods and drinks: Dark-coloured food/beverages like curry; soya sauce, coffee and tea can stain teeth over time. Enjoy them in moderation and rinse your mouth with water afterward.
- Quit smoking: Smoking is a major cause of tooth discoloration. Quitting can significantly improve the appearance of your teeth and benefit your overall health.
- Use a straw: When drinking staining beverages, use a straw to minimise contact with your teeth.
- Regular dental cleanings: Visit your dentist for regular cleanings and check-ups to remove surface stains and detect any early signs of tooth decay or other issues.
Teeth Whitening: Conclusion
Tooth discoloration can be a cosmetic concern for many people. Understanding tooth discoloration causes and the available treatment options can help you make informed decisions about your dental care. If you are considering teeth whitening, it’s important to consult with a dentist to determine the most appropriate and safe approach for your individual needs.
References:
Tooth Discoloration, https://my.clevelandclinic.org/health/symptoms/10958-tooth-discoloration, Accessed July 26, 2024
Tooth-bleaching, https://www.health.harvard.edu/staying-healthy/tooth-bleaching Accessed July 26, 2024
Discoloured Teeth, https://www.singhealth.com.sg/patient-care/conditions-treatments/discoloured-teeth Accessed July 26, 2024
