What is the direct answer?
Professional whitening products use a peroxide gel to oxidize colored molecules in enamel and dentin, with treatment choice based on your teeth and gums.
What does this question mean?
Crest professional whitening refers to a branded peroxide-based whitening system, not a diagnosis or a guarantee that every stain will respond.
What can you do next?
A dentist checks for decay, cracks, gum inflammation, restorations, and the type of discoloration before whitening. Existing crowns, fillings, and veneers do not lighten like natural teeth.
When should you seek dental care?
Arrange an examination for severe sensitivity, gum burns, uneven color, a dark single tooth, or discoloration that appeared without a clear cause.
What should you ask the dentist?
Ask which product and peroxide concentration are planned, whether restorations will match afterward, and how sensitivity will be managed.
Frequently asked questions
Can this be diagnosed without an examination?
The general principle can be explained, but an examination is needed to identify the cause and select treatment.
What happens if the underlying problem is ignored?
The condition may persist or worsen, so arrange dental assessment when symptoms continue or progress.

