Teeth whitening uses controlled bleaching products to lighten the colour of natural teeth. Surface stains and discolouration within the tooth do not respond in the same way. The cause of the colour change, oral health and existing restorations should therefore be assessed first.

Whitening does not change tooth shape or position and does not lighten fillings, crowns, bridges or veneers. Expectations should be planned according to natural tooth colour and existing dental work.

What Is Teeth Whitening?

Whitening agents act on colour-forming molecules within tooth tissue and help lighten the natural shade. The product, concentration, application time and method are selected according to oral health and sensitivity risk.

Why Do Teeth Change Colour?

External Staining

Coffee, tea, tobacco, coloured foods, plaque and calculus can stain tooth surfaces. Some external stains can be reduced through professional cleaning.

Internal Discolouration

Age-related dentine changes, selected medication during tooth development, fluorosis, trauma, root-canal treatment and developmental differences can affect internal colour. These changes respond differently to whitening.

What Is Assessed Before Whitening?

Active decay and leaking fillings
Gum inflammation or recession
Existing tooth sensitivity
Cracks and enamel loss
Fillings, crowns, bridges or veneers in visible areas
The type and cause of discolouration
Medication and general health information
Pregnancy, breastfeeding or other special circumstances

Existing disease may need treatment first. Timing is individualised.

In-Office Teeth Whitening

The gums are protected and a bleaching product is applied to the teeth in a controlled clinical setting. Treatment may involve one or more appointments depending on the product and protocol.

Some systems use a light or device, but the principal whitening effect is associated with the chemical product. A device does not guarantee a better or longer-lasting result in every case.

Custom Take-Home Whitening

A prescribed amount of whitening gel is placed in custom-made trays and used according to an individual schedule. Correct fit, gel quantity and wear time are important for reducing gum irritation and sensitivity.

High-concentration products obtained from uncontrolled sources can cause gum injury, severe sensitivity or uneven results when misused.

Can In-Office and Home Whitening Be Combined?

A clinical application and custom home trays may be combined in selected cases. This is not necessary for every patient. The desired change, sensitivity risk and ability to follow the programme are considered.

Do All Teeth Whiten Equally?

No. Yellow-toned natural discolouration often responds more readily, while grey, brown, trauma-related or developmental changes can respond less predictably. A single dark tooth requires assessment for root-canal history, cracks or trauma.

Do Fillings, Crowns and Veneers Whiten?

No. Composite, porcelain and zirconia restorations do not change colour with bleaching products. A shade difference can become more visible after whitening. Replacement of visible restorations, when needed, is normally considered after the tooth colour stabilises.

See Aesthetic Dentistry for restorative options.

Does Whitening Cause Sensitivity?

Temporary sensitivity to hot and cold is a common adverse effect. Contact with the gums can cause temporary irritation. Risk varies with product concentration, duration, previous sensitivity and tooth structure.

Reducing frequency, using desensitising products or pausing treatment may be considered. Severe or persistent pain requires assessment for another dental problem.

Does Whitening Damage Enamel?

Appropriate products are intended to be used at suitable concentrations and durations after professional assessment. Uncontrolled, frequent or acidic applications can damage teeth and gums. Home remedies involving lemon, bicarbonate or abrasive materials may wear the enamel surface and increase sensitivity.

Care After Whitening

Strongly coloured foods and drinks may be limited initially.
Avoid smoking and tobacco.
Brush and clean between teeth regularly.
Use recommended products for sensitivity.
Temporarily reduce very hot or cold foods if sensitive.
Do not add extra gel or products without advice.

How Long Does Whitening Last?

Duration depends on coffee, tea, tobacco, diet, oral hygiene and natural ageing. Whitening does not provide permanent colour stability. A supervised top-up may be considered when appropriate; frequent uncontrolled repetition is not recommended.

What Do Whitening Toothpastes Do?

Whitening toothpastes mainly help remove surface stains mechanically. They are not expected to lighten natural tooth colour to the same extent as bleaching. Highly abrasive products can contribute to sensitivity or surface wear.

What Is Internal Whitening?

For a selected root-treated tooth that has darkened internally, a bleaching product may be placed inside the tooth. The root-canal treatment and surrounding tissues must be reviewed first. Not every dark tooth is suitable.

Whitening or Veneers?

When natural tooth colour is the main concern, whitening may be the more conservative option. Shape changes, major fractures, permanent surface defects or discolouration that does not respond may require Dental Veneers, bonding or another restoration. The least invasive suitable approach is considered first.

Teeth Whitening at Ozant Dental Clinic

The cause of discolouration, gum health, restorations and sensitivity risk are assessed. The objective is a controlled change compatible with natural tooth structure and individual expectations rather than an artificial uniform shade.

Frequently Asked Questions

Is teeth whitening suitable for everyone?

No. Active decay, gum disease, significant sensitivity or selected health circumstances may require a different approach first.

Does whitening lighten fillings?

No. Fillings, crowns, bridges and veneers do not whiten.

How white will the teeth become?

Response varies with natural shade and the cause of discolouration. A specific shade cannot be guaranteed.

Is whitening sensitivity permanent?

It is usually temporary. Severe or persistent sensitivity should be assessed.

How often can whitening be repeated?

There is no universal interval. Oral health, previous treatment and staining habits should be professionally reviewed.

Appointment and Assessment

To assess tooth discolouration, sensitivity risk and the most suitable whitening approach, you can submit an appointment request.

Medical Information

This content has been prepared for general information. It does not replace a clinical examination, diagnosis or an individual treatment plan. The appropriate approach is determined after considering oral health, general health, clinical findings and individual needs. No particular treatment result, lifespan or suitability for every patient is guaranteed.

Last updated: 3 August 2026