There are now hundreds studies that evaluated the safety of bleaching agents on teeth and the whole body. This cosmetic treatment is among the safest cosmetic treatments .These studies have noted the safety of bleaching treatment is in a position to properly use both in experimental conditions in which they have been deliberately exaggerated the use .The analysis carried out by electron microscopy before and after bleaching treatment showed no change on the surface of the enamel, or changes in its structure and surface deep. As evidence of the safety of this product the Food and Drug Administration has classified car amide peroxide as "cosmetic agent", limiting the requests for tests and provisions for cargo use bleaching products containing it. In the by evidence based b evidence based medicine and dentistry (medicine and dentistry based on evidence, namely on the data of scientific research), these data confirm that processing brighteners are safe, effective and fast. Fallacy: there among some people the false myth that the bleached with chemicals damage the structure of tooth enamel: This is absolutely false, was demonstrated by dozens of studies that the structure of enamel does not change with the use of bleaching products Even those with a higher concentration. Paradoxically can cause more damage mechanical methods: an improper brushing with a toothbrush bristles hard over the years can lead to real tooth abrasion, causing damage and a strong aesthetic sensibility teeth that can be resolved only with the coverage of tooth with a prosthesis, the so-called "capsule" or dental crown.