Tooth washing is about several hundred yuan. Generally, you can't wash your yellow teeth into white when you wash your teeth. It can only remove stains, tartar, dental plaque and so on. Put it in your mouth and let the teeth return to their original appearance. If the teeth are naturally yellow, the washed teeth are still yellow, but there is no dirt attached. If yellow smoke stains are attached to the tooth surface due to smoking, they can be removed by tooth washing, that is to say, if yellow is the color emitted from the inside, it cannot be washed off. But if it adheres to the surface of teeth, it can be washed off. Yellow teeth that can't be washed out can be whitened with a cold light whitening instrument, but this effect can only last for a few years, and patients need repeated treatment.