These are alright, but I find them to take quite a long time to actually start to work. You have to do them as frequently as they recommend, and if you don't they won't really work. I would recommend trying other products first.

I bought these last week too remove the stains off my teeth and too brighten my smile. I normally wouldn't buy this as they are so painful on my teeth as they are extremely sensitive but it said "Gentle" on the box so I figured I would give these another try. When I opened the package and put them on my teeth I noticed the strips were super long so I would just cut them in half as it would be enough too fit my bottom and top teeth. I left them on for about 20 minutes and noticed that it wasn't painful which was great but what I did notice was the calcium deposits on my teeth were super super white and the rest of my teeth were a lighter white...It kinda looked funny as I had white dots all over my teeth. It did fad within a couple days.

I bought these for 45$ at Walmart super expensive but they would normally last me a good 6 months if I did them every couple of weeks.

Finished the whitening routine. There are about 10 - 12 strips I believe? First day I used it, saw a slight difference in the colour of my teeth which was great. At least I knew it was working. After the second one, I started noticing my teeth would hurt after the treatment. I guess my teeth care sensitive to he product. So I decided to spread the strips over a course of a month. Just to make it easier on my teeth. So in the end, I did see a slight difference in my teeth. and I would definitely recommend this product as it is effective in performance and value is good too.

Purchased these gentle routine white strips a year ago after reading reviews that other Crest 3D white strips cause sensitivity issues. I used them for about 2-3 weeks once a day (though for much longer than the recommended five minutes) and had outstanding results. These took off food stains and lightened by naturally yellowed teeth. I have fair skin and found that this made my teeth appear darker (unless wearing a dark lipstick) so I have been so happy that my teeth actually look white! I've been complimented by my dentist that I have "beautiful white teeth". Calcium markings on my teeth from my braces have now completely blended in. My dentist refused to perform professional whitening on my teeth fearing that this would make the calcium markings worse so this is a great alternative. I only use these about once a month now to keep them bright and have experienced absolutely no sensitivity. My family now also uses them after seeing how great my teeth look. I only wish the price was slightly lower compared to other 3D whitening strips as they are only supposed to be worn for a fraction of the time, so it seems a bit like a money grab.