Teeth Whitening Options and Risks | Guide for Patients

Teeth whitening has become one of the most popular cosmetic dental treatments worldwide. But with numerous options available — from professional in-office treatments to shop-bought strips — how do you choose? And what are the real risks involved? This comprehensive guide breaks down every whitening method and helps you make an informed decision.

Professional Whitening Options

Professional treatments performed by a qualified dentist remain the gold standard for safe, effective whitening. Here are your main options:

In-Office Power Whitening

This is the fastest route to a dramatically whiter smile. At our South Kensington clinic, we use advanced systems that can brighten teeth by up to 8 shades in a single one-hour session.

How it works:

• Your dentist protects your gums with a special barrier or shield
• A high-concentration hydrogen peroxide gel (25-40%) is applied to your teeth
• An LED or laser light activates the gel, accelerating the whitening process
• The process is repeated 2-4 times in the same appointment

Pros: Immediate, dramatic results; professionally supervised; custom treatment based on your needs

Cons: Higher initial cost; may cause temporary sensitivity; requires dental appointment

Typical cost: £350-£700 per session

Custom Take-Home Whitening Trays

Your dentist creates custom-fitted trays from impressions of your teeth, along with professional-grade whitening gel to use at home.

How it works:

• Impressions are taken and custom trays are fabricated
• You fill the trays with whitening gel (typically 10-22% carbamide peroxide)
• Wear for 30 minutes to several hours daily, depending on the formula
• Treatment continues for 1-3 weeks until desired results are achieved

Pros: Professional-grade results; ability to top up whenever needed; more affordable than in-office; custom fit minimises gum irritation

Cons: Slower results; requires discipline to use consistently; initial dental visit required

Typical cost: £200-£400 for the kit

Combination Treatments

Many patients achieve optimal results by combining an in-office session for immediate brightness, followed by custom trays for maintenance. This approach provides the best of both worlds.

Over-the-Counter Options

Shop-bought whitening products are more accessible but come with important limitations:

Whitening Strips

Pre-coated plastic strips that adhere to teeth for a set period.

Effectiveness: Can lighten teeth 1-3 shades with consistent use over 2-4 weeks

Limitations: One-size-fits-all design may not cover all teeth evenly; lower concentration means slower results; can slip or feel uncomfortable

Whitening Toothpastes

Contain mild abrasives and low concentrations of whitening agents.

Effectiveness: May remove surface stains but cannot change the intrinsic colour of teeth

Limitations: Results are minimal; abrasives can damage enamel with overuse; not suitable for deep staining

LED Whitening Kits

Home kits with LED lights and whitening gels.

Effectiveness: Varies widely; most contain lower concentrations than professional products

Limitations: Trays are not custom-fitted; LED lights are often lower powered than professional equipment; results may be uneven

Whitening Pens

Brush-on gel applicators for touch-ups.

Effectiveness: Minimal; best for maintaining results rather than achieving significant whitening

Limitations: Low concentration; gel can be washed away by saliva quickly

Understanding the Risks

While teeth whitening is generally safe when performed correctly, there are risks to be aware of:

1. Tooth Sensitivity

This is the most common side effect, affecting around 60% of patients to some degree. The whitening agents temporarily open microscopic tubules in the enamel, exposing the nerve to temperature changes.

How to minimise:

• Use desensitising toothpaste before and after treatment
• Choose a lower-concentration gel if you have sensitive teeth
• Allow adequate time between treatments
• Follow your dentist's instructions carefully

Duration: Usually resolves within 24-72 hours, rarely lasting more than a week

2. Gum Irritation

If whitening gel contacts your gums, it can cause temporary irritation, white spots, or a burning sensation.

How to minimise:

• Professional treatments include gum protection
• Use custom-fitted trays rather than one-size-fits-all products
• Avoid overfilling trays with gel
• Wipe away any gel that contacts gums immediately

Duration: Usually resolves within hours to a day

3. Enamel Damage

Overuse of whitening products or using products with harsh abrasives can potentially damage tooth enamel.

How to minimise:

• Follow recommended treatment schedules — more is not better
• Don't leave whitening products on longer than directed
• Avoid whitening toothpastes with high abrasive content
• Have your dentist assess your enamel health before treatment

4. Uneven Results

Whitening doesn't work equally on all types of discolouration, and existing dental work won't change colour.

What whitening DOES improve:

• Yellow staining from food, drinks, and ageing
• General dullness or lack of brightness
• Surface stains from coffee, tea, and wine

What whitening DOES NOT improve:

• Crowns, veneers, fillings, or bonding
• Grey discolouration from trauma or medication
• Tetracycline staining (may improve but rarely eliminates)
• Fluorosis (white spots from excess fluoride)

5. Overbleaching

Excessive whitening can make teeth appear unnaturally white, translucent, or chalky.

How to avoid:

• Set realistic expectations — natural white, not Hollywood white
• Work with your dentist to determine the right shade goal
• Stop treatment once you've achieved your desired results
• Space out top-up treatments appropriately

Who Should Avoid Whitening?

Whitening isn't suitable for everyone. You should avoid or postpone treatment if you have:

• Untreated cavities or gum disease — These must be addressed first
• Worn enamel or exposed roots — Increased sensitivity risk
• Pregnancy or breastfeeding — Safety not established
• Children under 16 — Pulp chamber is still large, increasing sensitivity risk
• Allergies to peroxide — Alternative treatments may be needed
• Extremely sensitive teeth — May need desensitising treatment first

Making the Right Choice

When deciding on a whitening method, consider these factors:

Your Starting Point

If you have significant staining or want dramatic results, professional treatment is your best option. Mild surface stains may respond to quality over-the-counter products.

Your Timeline

Need results for a special event? In-office whitening delivers immediate results. If time isn't a factor, take-home trays offer flexibility.

Your Budget

Professional whitening has a higher upfront cost but provides better, longer-lasting results and is safer. Over-the-counter products may seem cheaper but often require repeated purchases.

Your Dental Health

Always have a dental check-up before whitening. Existing cavities, cracks, or gum issues need to be addressed first, and your dentist can recommend the safest approach for your situation.

Maintaining Your Results

Whatever method you choose, maintaining your brighter smile requires ongoing care:

• Avoid staining substances for 48 hours after treatment (coffee, tea, red wine, berries, curry, tomato sauce)
• Use a straw for dark-coloured beverages
• Rinse or brush after consuming staining foods
• Maintain excellent oral hygiene with twice-daily brushing and daily flossing
• Schedule regular hygiene appointments to remove surface stains
• Consider touch-up treatments every 6-12 months

The Bottom Line

Teeth whitening is a safe and effective way to enhance your smile when done properly. The key is choosing the right method for your needs and having realistic expectations about results.

For the safest, most effective results, we always recommend professional whitening under dental supervision. Your dentist can assess your suitability, customise your treatment, and ensure you achieve beautiful results without compromising your dental health.

Ready to explore your whitening options? Book a consultation at our South Kensington clinic, and we'll create a personalised plan to help you achieve the bright, confident smile you deserve.