Colgate Optic White O2 Whitening Pen

I like this as it is very easy to use and very minimal steps. As compared to another one I have used before which requires another device.

The Colgate Optic White O2 Whitening Pen works for me. However I feel that it is hard to remove the whitening thing on my teeth the next morning. The smell and taste of the product is not pleasant.

Slight tingling sensation on the gum upon application but is still acceptable. Can feel teeth is slightly whiter.

I'm surprised at the ease of use and it turns my teeth slightly whiter even though I'm a coffee and tea drinker.

I really like how easy it is to use this Colgate Optic White O2 Teeth Whitening Pen. Just a pump after it starts oozing out, I was able to easily apply it. It helps to lighten my teeth as I like drinking tea, and it doesn’t cause any sensitivity for me.

Colgate Optic White O2 Whitening Pen really helps to lighten the stain on my teeth. My teeth looks slightly whiter than before. The pen is easy to use however the brush will get hardened from the gel and I had to wash it away. I also find it difficult to know whether I had applied the gel on my teeth as it is clear in colour.

I really like the product because after using it for 21 days, I am able to observe a noticeable difference of the shade of my teeth. My teeth are at least one shade whiter as compared to before. The application is also made really convenient and easy which I have absolutely no troubles with.

The whitening pen is easy to use and effective. The stains were reduced with continuous use.

Unsure whether it adds to teeth sensitivity Was certainly thrilled when I received the sample whitening pen as I have been looking for teeth whitening solution for quite a while. Tried everything from tooth sticker, dental gargle, expensive toothpaste - you name the list and I would have tried my hands on them yet there was none really that worked. The appearance of this item screams slight premium. The sleek black and red design had me so excited to get right into action. Upon application, the liquid forms a plastic-like film on my teeth, and I was supposed to leave it on throughout the night. After the first two to three nights I did notice slight whitening effect. However, starting day 4 I started getting sharp sensation on my gum when it got into contact with the liquid accidentally. This continued for another 2 days. Hence the title of my review, whether this item causes sensitivity in any case.

Effortless to get whitening teeth in three weeks time.

Colgate Optic White O2 Whitening Pen helps to whiten my teeth slightly! But if you are a frequent coffee drinker, it will take a while to see the effect. I use it before I sleep and seal them in my teeth aligners!

After using Colgate Optic White O2 Whitening Pen daily before I sleep, I noticed visible results as my teeth became a shade whiter. It didn't hurt my enamel so it's all good. #htcsgxColgateO2Pen

The serum does provide a slight lightening effect but not as effective as a full whitening session. Good for maintenance. Did not observe 3 shades lighter as claimed.

This is quite an effective whitening pen. I observed that my teeth is 1 or 2 shades lighter than before after using.

Super impress with this sleek and handy design. No Sensitivity after using but I’m not sure for long term will it thin my enamel as whitening products are very abrasive and harmful. One big problem I had was that it started smelling bad after 1 week. If you don’t brush and floss well, plaque starts to accumulate on the brush tip and it will spread potential bacteria that will cause decay so do remember to brush and floss throughly before using this!