A. I just need you to understand that the strips will not make your teeth yellow- I don’t know if you have eaten something highly coloured in the first 24-48 hours ater whitening. This can sometimes have a re-bound affect on whitened teeth. You also need to be aware that there is a limit to how light your teeth will go. If you find that the classic strips work best for you, then stick with them. It’s a personal choice. good luck.