TREATMENTS
Teeth whitening
Professional whitening lightens natural tooth structure using peroxide-based whitening agents.
SHORT ANSWER
Professional whitening lightens natural tooth structure using peroxide-based whitening agents. It does not change the colour of existing crowns, veneers, fillings or bridges.
Why an examination comes first: Tooth discolouration can have different causes. Existing decay, cracks, gum recession, exposed dentine or defective restorations may affect sensitivity or the treatment plan. Aesthetic expectations should also account for restorations that will not whiten with the natural teeth.
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Why an examination comes first
Tooth discolouration can have different causes. Existing decay, cracks, gum recession, exposed dentine or defective restorations may affect sensitivity or the treatment plan. Aesthetic expectations should also account for restorations that will not whiten with the natural teeth.
Sensitivity
Temporary sensitivity is one of the most common adverse effects. Its likelihood and intensity vary between people and protocols. Desensitising strategies and changes in concentration or exposure can be considered when appropriate.
Whitening versus cleaning
Professional cleaning removes plaque, calculus and some surface stain. Whitening changes the colour of the tooth structure. They solve different problems and one should not be sold as a substitute for the other.
After whitening
Colour can gradually change again with time, diet, smoking and natural ageing. Maintenance is individual; “permanent whitening” is not a realistic promise.
Internal and external discolouration
Surface stain from food, smoking or plaque behaves differently from colour changes within the tooth. Some intrinsic discolouration responds less predictably to conventional whitening and may need a different discussion.
Restorations create a shade-matching problem
Crowns, veneers and composite fillings do not whiten like natural teeth. If visible restorations are present, it may be sensible to whiten natural teeth first and reassess restoration shade afterwards rather than replacing restorations before whitening.
Whitening is not a substitute for diagnosis
A single dark tooth can reflect trauma, pulpal changes or previous root canal treatment. Localised discolouration deserves assessment rather than simply stronger whitening gel.
Questions to ask
- Is my colour concern mainly surface stain or intrinsic colour?
- Which visible restorations will not change colour?
- What sensitivity should I expect?
- How long should I wait before matching new restorations to a whitened shade?
Frequently asked questions
Can whitening damage enamel?
Temporary sensitivity and gum irritation are recognised adverse effects of peroxide whitening. Stronger or longer application can increase problems, so use the product only as directed. Existing cracks, decay or exposed dentine need assessment before whitening; persistent or severe pain should be reviewed.
How white will my teeth become?
Response varies, so the exact final shade cannot be predicted in advance.
Office and home-supervised approaches
Professional whitening can use chairside protocols, dentist-supervised home trays or combinations depending on the product and case. Different approaches balance concentration, exposure and convenience. A faster protocol is not automatically more effective or more appropriate for a sensitive patient.
Timing around restorative treatment
If new anterior restorations are planned, whitening may be completed first so the natural teeth can settle to a more stable shade before the final ceramic or composite colour is selected. This can reduce the risk of making new restorations that immediately look mismatched.
Maintenance and expectations
Whitening does not stop natural ageing or exposure to staining habits. Touch-up treatment may be considered later, but frequency should follow the product and clinical context rather than a fixed subscription-style schedule.
References and verification links
- https://www.ada.org/resources/ada-library/oral-health-topics/whitening
- At-home vs In-office Bleaching: An Updated Systematic Review and Meta-analysis (2025)
- Comparison of in-office and at-home bleaching techniques: An umbrella review of efficacy and post-operative sensitivity (2024)
- Clinical decision-making in tooth bleaching based on current evidence: A narrative review (2025)
- Effect of at-home agents and concentrations on bleaching efficacy: A systematic review and network meta-analysis (2025)
- Effect of at-home bleaching agents and concentrations on tooth sensitivity: A systematic review and network meta-analysis (2025)
- Do Laser and Light Activation Improve In-Office Dental Bleaching Outcomes? An Umbrella Review of Efficacy, Tooth Sensitivity, and Biological Safety (2026)
- White diet is not necessary during dental bleaching treatment: A systematic review and network meta-analysis of clinical studies (2024)
- https://www.nhs.uk/tests-and-treatments/teeth-whitening/
This page provides general information and does not replace an in-person dental examination, diagnosis or an individual treatment plan.