Tooth black stains may be the emergence of dental calculus, dental caries, may also be caused by pigmentation, can be ultrasonic scaling, resin filling or cold light whitening. 1. Ultrasonic scaling, if attached to the teeth is plaque plaque can generally be removed by ultrasonic high-frequency vibration, can effectively relieve the teeth of black stains. 2. Dental caries: local cleaning is not in place, bacterial invasion of dental tissues, resulting in caries, can be presented as black, need to grind away the decayed tissue, resin filling. 3. Cold light whitening, if it is caused by tooth pigmentation, you can choose to carry out cold light whitening, cold light whitening is generally irradiated with a cold light lamp, through the optical treatment, so that the surface of the teeth redox reaction, so as to alleviate tooth pigmentation. Usually need to pay attention to personal oral care, it is best not to often eat food containing more pigment, but also need to prevent caries.