Teeth have yellow color stains, it may be food residue, soft tartar and so on, or calculus, according to the situation, choose to remove it by brushing or cleaning. 1. Brushing: The stains are soft and may be food residue, soft scale, etc. They can be removed by brushing. Toothpaste contains friction agents or foaming agents, etc., which can rub off the pigment on the surface of the teeth, so that the teeth will gradually restore their brightness, neatness, etc. 2. Scaling: Dental stains are hard and may be calculus, which can be removed by scaling. Dental scaling includes manual scaling and ultrasonic scaling, ultrasonic scaling is more effective, the use of ultrasonic vibration to remove plaque and calculus attached to the surface of the teeth, so that the teeth to restore the brightness. Yellow stains on the teeth should not be treated blindly on their own, go to the hospital in a timely manner to check and clarify the cause of the disease and then actively treat it.