Patients undergo ultrasonic scaling through full mouth cleaning, which removes pigmentation such as smoke stains, tea stains, and coffee attached to the tooth surface, which restores the original color of the teeth, but does not achieve a whitening effect. If you are still dissatisfied with the color of your teeth after the full mouth cleaning, you can use the teeth whitening method, which is to use bleaching agents to bleach your teeth. The treatment method is to apply a layer of whitening agent on the surface of the teeth and whiten the teeth by cold light irradiation for about eight minutes each time, three times in total, and the teeth will achieve a very good whitening effect.