Last week !!!!!
And I have enjoyed using this mouth wash because I could see my teeth getting whiter and cleaner in just 3 days of starting with it. I have yellow ish stains in my before pics and right now I can see a major difference in colour.
So my routine is normally rinsing twice a day. And I'd like to advise that everyone invests in a good toothbrush.

A brighter smile definitely boosts confidence. A smile says a lot about a person and you can get away with a lot of things by just smiling your through hahahahahaha !
So Listerine has definitely given me th confidence to smile often.