 and keeps them white every day just by brushing your teeth. I never thought that whitening my teeth could be so easy. I just put the gel on the brush, the toothpaste on it, brush, and I can see my white teeth. Simply add Smile Active to any toothpaste and our patented Polyclean technology activates into a powerful microfoam that penetrates into the enamel surface to safely lift and remove stains.