I tried this out last week, and just finished with the last 2 ampules as a follow-up. I endured the slight sensitivity I felt when doing the 2 hr application. However, upon applying the follow-up, I felt an uncomfortable, numbing sensation on my top gums. My gumline was white. After using the whole package, my teeth are definitely not white as the procedure done at the dentist. But they're "slightly" white. I'm divided on whether I should buy it again for the next month. Or maybe I'll look for something more promising.

I just finished using this product, and I can honestly say that it is absolutely useless. I didn't experience any pain like some other reviewers, but my teeth are not any whiter or brighter. I bought it because it was cheaper than the other brands,now I know why :(

I don't have too noticeably yellowed teeth, so I expected something better for results. It hurt my teeth and gums and managed to get onto my tongue, also. Once I went through all that, I still saw no difference! Now my teeth hurt.

I am really, really impressed with this product! It was PAINLESS, FAST, and EFFECTIVE! I've tried several other kits including Whitestrips and the overnight paint-on gunk, which made me gag and some sent huge jolts of pain through my head. Most of them I never finished because they were torturous, too time consuming or ineffective. First off, there are 3 full syringes in this kit, which covers 3 full 2 hour treatments (four 20 minute treatments with 10 minute breaks) and several touch-ups in between. USE SPARINGLY. I had noticeably whiter teeth after the first 20 minute session (and my teeth were not particularly stained to begin with). There was no discomfort at all until the third treatment and then it was only mild gum sensitivity -- I went ahead and finished the fourth. The trays were surprisingly comfortable and very easy to mold. I am dazzled!

As of now I can't make a sure prediction; on the bright side I didn't feel any pain at all - just a tingle here and there. My only problem is that my teeth weren't that different after the 2 hour process. I think like most things I have to wait, that's why I think they gave more than one of gel syringes. For now, I recommend this product to help out.

I love this product! Although you do experience some tooth sensitivity it's totally worth it! I only used it for 3 sessions and was really happy about the results, it's definitely worth your time. Unless you cover your gums with the gel, you shouldnt have a problem. I know because I have super sensitive teeth. I will definitely use this product again. I didn't even use a full syringe for 3 sessions! It worth your time and money!!!

I LOVE this stuff! Some of the reviews sounded scary, but as they say, YMMV (your mileage may vary). I tried the trays and found them to be too big, so I used custom trays I kept from whitening with a dentist. I felt minimal tooth sensitivity and no gum pain. I think some of the problems that people have may be due to using too much gel. I had at least seven 20-minute treatments last week and I still have enough gel in the first tube for 2-3 more treatments. Less is definitely better. After reading ALL the reviews I decided to try the Comfy Trays. I heated them and they do a pretty good job if you have no other alternative. Make sure the gel doesn't get on your gums and if you feel gum pain, remove immediately to avoid damage. I didn't mind the taste. Other gels I have used tasted yucky. I have used other treatments, including the one at the dentist that uses intense light. I got burned lips and surprisingly little improvement in color. Not fun. This product works great and it seemed safe too.

The product does what it claims. I noticed some whitening after the first application and further more after the second. It's not a terribly pleasant experience; the gel doesn't taste great and it tends to foam a bit, but I am willing to suffer for the 20 minutes for the whitening effect. I bought a prescription whitening kit from my dentist about 5 years ago and I found that the Rembrandt kit produced similar results for a 1/4 of the price.

I liked the product; it did what it claimed. Obviously anyone will experience tingling and some pain in the gums - you are bleaching! This is not a miracle, but I did like that my teeth were whiter and lasted for a few weeks before having to whiten again.

I definitely recommend this product. I've used Crest Whitestrips and Colgate whitening gel in the past, and this one gave me a better result. I think it's because you can control better how much gel and where it goes on your teeth. This product whitened my teeth well, but I had to use it 3 times though (2 hours in 3 different days). First I used it for 2 days in a role, however I experienced sensitivity in my gums/teeth, so I took a 2 day break, and then used it again. I think I went about 3 to 4 shades whiter, and I'm still going to use it maybe one more time. A little gel goes a long way, and that's what made me able to use one package 4 times.