In the present work some results of the comparative measurements of the tooth whitening effect using a bleaching agent activated by Ar+ (emitting at 488 nm) and CuBr (emitting at 510 nm) lasers are reported. It is shown that the whitening effect is observed in both cases. Some of the peculiarities in application of CuBr laser in the field of aesthetic dentistry are discussed, as well as the possibility to replace the more expensive Ar+ laser. In order to ensure reliable results from a light-chemical treatment of the teeth, as spectroscopy method has been developed and applied. The method is based on the analysis of laser-induced fluorescence spectra of the teeth with different coloring.