Review on 🦷 Crest 3D Whitestrips 1 Hour Express Teeth Whitening Kit - 7 Treatments for Fast Results by Jeremy Lane

13. These are the most effective, second time buying. My teeth are sensitive and they hurt for a few days afterwards, but I only use it once. Noticeable difference after just one treatment. I have them in my office and use them from time to time/about once a month. There's no reason to use them every day. I would recommend them to others. Tip: I always remove the strip and then stretch it a bit. Thus, it covers a large area of the tooth. I take my fingernail and press it between my teeth, folding the strip down. I then place a cotton swab under my tongue and set an hourly timer so I don't feel like spitting out the product or tasting it.