MarketplaceCrest Vivid WhitePosted on March 11, 2010. How long will it take Crest Vivid White to work for a 14 year old? I recently purchased toothpaste Crest Vivid White and I really want to know how long I'll actually start seeing results. And I'm using the white stripes, at the same time. Luckily, you should begin to see visible results within a few weeks ... good. keep a pot never boils. If you are agitated, it seems an eternity until you see the results. Relax and add it to your daily routine, you will see results when you see them, but it will probably be out somewhere from 6 days to 2 weeks. Good luck! CommentsThere are no comments.Leave a Comment | Popular My Friends |