Dental bleaching is an initial step in the analysis and reproduction of smile aesthetics, so it is very important that the dentist knows how to diagnose the causes of color change and to indicate whitening before proposing the appropriate dental procedure. With the technological advance, dental bleaching techniques have emerged to facilitate its use and improve comfort, safety and time reduction in the execution of the technique. The conventional means of external dental whitening is with carbamate or hydrogen peroxide photoactivated or not. However, the home and office whitening procedure causes dental sensitivity. There is a new bleaching proposal on the market without the use of bleaching gels, thus reducing post-treatment sensitivity. Such a proposal elucidates ultraviolet light as a bleaching agent.