... refraction effects, so that the tartar peeling off the teeth, but the teeth There is no injury, and get neatness, whitening.1 ... by tea, coffee, smoking and food residue.2. Whitening teeth: low-frequency ultrasound penetration into the gum inside, not to ... hurt the gums and to protect teeth white composition, make the teeth glossy naturally.3. Bactericidal anti-inflammatory: cavitation shock ...