In office whitening systems
In-office whitening uses dentist-applied peroxide gel while the gums are protected and the treatment is timed and controlled.
The short answer
In-office whitening uses a dentist-applied peroxide gel, with the gums protected while the gel is activated for timed intervals and then removed. The dentist checks the teeth and restorations first.

What is the direct answer?
What does this question mean?
The system may use hydrogen peroxide or carbamide peroxide, sometimes with a light or other activation method. The gel breaks down stain molecules within enamel and dentin, while fillings, crowns, and veneers keep their original shade.
What can you do next?
A dentist records the starting shade, isolates the gingiva, applies the gel in controlled cycles, rinses it away, and checks comfort and colour. Follow instructions about sensitivity, acidic foods, and staining drinks after treatment.
When should you seek dental care?
Ask for an examination before whitening if you have decay, cracks, gum disease, exposed roots, or strong sensitivity. Contact the dentist if pain is severe, a chemical burn develops, or symptoms persist after treatment.
What should you ask the dentist?
Ask which peroxide is used, how the gums will be protected, how existing restorations will compare, and which alternatives are available if sensitivity makes whitening unsuitable.
Frequently asked questions
Can I manage this at home?
A dentist records the starting shade, isolates the gingiva, applies the gel in controlled cycles, rinses it away, and checks comfort and colour. Follow instructions about sensitivity, acidic foods, and staining drinks after treatment.
What will a dentist check?
Ask which peroxide is used, how the gums will be protected, how existing restorations will compare, and which alternatives are available if sensitivity makes whitening unsuitable.
