Even though I use a basic whitening toothpaste twice a day, my teeth were still yellow. I am almost done with my whitening kit, and I am very pleased with the results! My teeth are not as white as a wedding gown (like the commercial), so I'm wondering if I should've bought the Advanced kit. I can't find anywhere on the website if I can use another 14-day kit a few weeks after fininshing this one (just read they can be used twice a year).