... and concha hallotidis.Function: It can oxidate yellow and black tooth caused by smoking, tea, coffee, red wine, areca ... catechu, food color, tetracycline pigmentation teeth to make tooth become white and shiny, At the same time, it ... or toothpaste when brush tooth. 1-2 times a day.Precaution:1. Pls flush with water once put it ... should use cautiously.Expiry Date: 3 years tooth whitening products