The whitening gel contains an active ingredient called Carbamide Peroxide. The Carbamide Peroxide degrades in the mouth to release oxygen. The oxygen reacts with the organic stains and discolourations within the teeth, breaking them up into smaller particles that do not absorb as much light and thus making them appear less dark, which makes the teeth whiter without damaging them. Artificial teeth and fillings are not affected by whitening.
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