A brighter smile is one of the most requested cosmetic dental treatments. But with so many whitening options available — from supermarket strips to in-chair treatments — it's important to understand what actually works, what's safe, and what will give you the results you're after.
Why Do Teeth Become Discoloured?
Tooth discolouration falls into two categories:
Extrinsic Staining (Surface) Stains on the outer surface of the enamel, caused by: - Coffee, tea, and red wine - Tobacco use - Deeply coloured foods (berries, curry, soy sauce) - Poor oral hygiene allowing plaque and tartar buildup
Intrinsic Staining (Internal) Discolouration within the tooth structure, caused by: - Natural ageing (enamel thins, revealing yellowish dentine) - Certain medications (especially tetracycline antibiotics during childhood) - Excessive fluoride exposure during tooth development - Trauma to a tooth - Genetic factors
Understanding the type of staining you have helps determine which whitening approach will be effective.
Professional Whitening Options
In-Chair Whitening
Professional in-chair whitening is performed at the dental clinic and offers the most controlled, predictable results.
How it works:
1. Your gums and soft tissues are protected with a barrier
2. A professional-strength whitening gel (containing hydrogen peroxide or carbamide peroxide) is applied to the teeth
3. The gel is activated and left to work for a specified period
4. The process may be repeated in the same session
5. Results are visible immediately
Advantages:
- Results in a single visit (typically 60–90 minutes)
- Professionally supervised for safety
- Higher concentration gels for more dramatic results
- Gums and soft tissues are protected throughout
Take-Home Professional Kits
Your dentist provides custom-fitted trays and professional-grade whitening gel for use at home.
How it works:
1. Impressions of your teeth are taken to create custom trays
2. You apply the whitening gel to the trays
3. Trays are worn for a specified period daily (usually 30 minutes to overnight, depending on the product)
4. Treatment continues for 1–3 weeks
Advantages:
- More gradual, natural-looking results
- Custom trays ensure even coverage and reduce gel contact with gums
- Can be used for maintenance after in-chair whitening
- Lower concentration gel means less sensitivity for many patients
Over-the-Counter vs. Professional Whitening
| Feature | Over-the-Counter | Professional |
|---------|-----------------|-------------|
| Concentration | Low (up to 6% hydrogen peroxide in Australia) | Higher (up to 35%+ in-chair) |
| Custom fit | One-size strips or generic trays | Custom trays moulded to your teeth |
| Supervision | None | Dentist-supervised |
| Results | Mild improvement | More significant and predictable |
| Gum protection | Limited | Professional barrier applied |
| Duration of results | Shorter | Longer-lasting |
| Addressing cause | Surface stains only | Can address some intrinsic staining |
Over-the-counter products can provide modest improvement for mild surface staining. For noticeable, lasting results — especially for intrinsic discolouration — professional whitening is more effective.
What Whitening Can and Cannot Do
Whitening CAN: - Lighten natural teeth by several shades - Remove or reduce extrinsic stains - Address some age-related yellowing - Boost confidence in your smile
Whitening CANNOT: - Change the colour of crowns, veneers, or fillings (these would need to be replaced to match) - Fix all types of intrinsic staining (severe tetracycline stains, for example, may not respond well) - Provide permanent results — maintenance is needed
Is Teeth Whitening Safe?
Professional teeth whitening, when performed or supervised by a dentist, is considered safe. However:
- Temporary sensitivity is the most common side effect — it typically resolves within a few days
- Gum irritation can occur if whitening gel contacts soft tissues (professional application minimises this)
- Overuse of whitening products can damage enamel — follow your dentist's instructions regarding frequency
At Shine Dental, Dr. Cho assesses your oral health before recommending whitening. Cavities, cracks, and gum disease should be addressed first, as whitening gel can cause discomfort when it reaches compromised areas.
How Long Do Results Last?
Whitening results are not permanent. How long they last depends on:
- Diet — frequent consumption of staining foods and drinks accelerates re-staining
- Smoking — tobacco is a major contributor to tooth discolouration
- Oral hygiene — consistent brushing and flossing helps maintain results
- Maintenance treatments — periodic touch-ups with take-home trays can extend results
With good habits, professional whitening results typically last 1–3 years before a touch-up is needed.
Tips for Maintaining Your Whiter Smile
- Rinse with water after consuming staining beverages
- Use a straw for coffee, tea, and coloured drinks
- Brush (or at least rinse) within 30 minutes of eating staining foods
- Maintain regular dental check-ups and cleans
- Avoid tobacco products
- Use a whitening toothpaste for daily maintenance (not as a primary whitening method)
Frequently Asked Questions
How white will my teeth get?
Results vary depending on the type and severity of staining, the natural colour of your teeth, and the whitening method used. Dr. Cho will discuss realistic expectations during your consultation.
Does whitening damage enamel?
Professional whitening used as directed does not damage healthy enamel. The active ingredients temporarily open the pores of the enamel to remove stains, and these pores remineralise naturally.
Can I whiten my teeth if I have sensitive teeth?
Yes, but modifications may be needed — such as using a lower concentration gel, shorter application times, or a desensitising treatment. Discuss your sensitivity with Dr. Cho before starting.
Is whitening suitable for teenagers?
Professional whitening is generally not recommended for patients under 16, as the tooth pulp is still developing. Dr. Cho can advise on appropriate timing.
Brighten Your Smile with Confidence
If you're considering teeth whitening, start with a professional assessment at Shine Dental. Dr. Cho will evaluate your oral health, identify the cause of discolouration, and recommend the most effective approach for your situation.
We welcome patients from Newington, Sydney Olympic Park, Wentworth Point, Auburn, Silverwater, and Lidcombe.
Call (02) 9748 4822 or book a consultation.
Shine Dental — Unit 5, 8 Avenue of Americas, Newington NSW 2127
Open Mon–Wed & Fri 9am–5pm, Thu 9am–12pm