Why Teeth Discolour — and What You Can Do About It
Tooth discolouration is extremely common and can result from food and drink (coffee, tea, red wine), tobacco use, ageing, certain medications, or trauma. The good news is that teeth whitening is one of the most accessible cosmetic dental treatments available — but not all whitening methods are created equal.
Understanding How Whitening Works
Most whitening products use hydrogen peroxide or carbamide peroxide as the active bleaching agent. These compounds penetrate the enamel and break down the chemical bonds that cause staining, making teeth appear brighter. The key differences between whitening options come down to the concentration of the bleaching agent and how it's applied.
Comparing Your Options
| Method | Strength | Duration | Results | Best For |
|---|---|---|---|---|
| In-Clinic Whitening | High concentration | 1–2 hours | Immediate, dramatic | Fast results, deep staining |
| Take-Home Trays (from dentist) | Medium-high | 1–2 weeks of nightly use | Gradual, even | Convenience, customised fit |
| OTC Strips/Gels | Low-medium | 2–4 weeks | Mild improvement | Maintenance, mild staining |
| Whitening Toothpaste | Very low (abrasive) | Ongoing | Surface stain removal only | Daily maintenance |
In-Clinic Whitening
Performed by your dentist, in-clinic (or "chairside") whitening uses a high-concentration bleaching gel, often activated with a light or laser. Results are visible immediately. This is the most effective option for significant staining, and the process is supervised for safety — gums are protected before treatment begins. It is also the most expensive route.
Dentist-Supplied Take-Home Kits
Your dentist creates custom-fitted trays from impressions of your teeth. You fill these with a professional-grade whitening gel and wear them for a set period each day or night. The custom fit ensures even coverage and reduces gel contact with gum tissue. Results develop gradually and are often long-lasting with good oral hygiene.
Over-the-Counter Products
Whitening strips, paint-on gels, and similar products are widely available at pharmacies. They are more affordable but contain lower concentrations of bleaching agents. Results are more modest, and because these aren't custom-fitted, uneven whitening or gum irritation is possible. They work best for maintaining results achieved through professional treatment.
Important Considerations Before Whitening
- Whitening does not affect crowns, veneers, or composite fillings — these will remain their original shade while natural teeth lighten.
- Sensitivity is common — many people experience temporary tooth sensitivity during or after treatment. Using a sensitivity toothpaste helps.
- Existing dental issues should be treated first — cavities or gum disease should be addressed before any whitening procedure.
- Results are not permanent — lifestyle habits like coffee drinking will gradually re-stain teeth over time.
Which Option Is Right for You?
If you want fast, significant results for a special occasion, in-clinic whitening delivers. For a more affordable, gradual approach with professional-grade results, dentist-supplied take-home trays are excellent. Over-the-counter products are useful for ongoing maintenance but work best when expectations are realistic. Speak with your dentist about which approach suits your teeth, lifestyle, and goals.