Most recently, I wanted to try the Beyond Polus system. I decided to carry out this procedure in the clinic "Dudko and Sons." At first I was skeptical of this type of whitening, so I did not count on a special result. But I really liked him. The teeth, although they did not become straight snow-white, but became much better than they were. I did not see any side effects, in the form of the appearance of tooth sensitivity or dark spots. I want to say a big thank you to the staff for their professional approach.