Gosmile Advanced Formula b1 Ampoules, $89

“Easy and fun to use,” these were a hit with impatient testers, who began to see a difference right away (just rub the end of the swab on each tooth).
Time Commitment: Two minutes to apply, plus 20 minutes without eating or drinking, twice a day for 7 to 10 days.
To Buy: www.gosmile.com.