Americans spend billions of dollars per year on teeth whitening. But not everyone can find a effective method for teeth whitening. The methods to whiten teeth vary. Teeth whitening can be carried out by a dentist, which can be up to 8 hours at a time.
When we chew food, food residue is easy to be left in our oral cavity, especially beside the teeth. Most people only use a toothbrush to clean their teeth. The normal way can clean the food residue at the appearance of teeth.