Dr Song Teeth Whitening Kit 44% Carbamide Peroxide

I received this teeth whitening kit and followed the instruction exactly. I have been using it for about 4 weeks. Getting the trays fitted took a little bit, because I had to remold several times to get a good fit. After that I trimmed away the edges until they felt smooth and nothing was rubbing or scratching the gums or tongue. Next, taking the gel and putting in the areas of the front teeth only. I did use the light that is included in the kit. I wore them 15 min. three times a week and my teeth have whitened very nicely! I did have some sensitivity, so I would follow using the gel for people like me who have sensitive teeth. That gel is sold separate. All in all this is a very good whitening system. If you have extra sensitive teeth I suggest getting a lower percentage instead of the 44%. I will have to say once again all the products I have tried from Dr Song have been great!!