In a method for operating a laser system for bleaching teeth, a water-containing bleaching agent applied onto teeth is heated by a laser beam, wherein the laser beam has a wavelength in a range of 2.6 μm, inclusive, to 3.1 μm, inclusive, or in a range of 9.0 μm, inclusive, to 11.0 μm, inclusive. The laser system is operated in pulse mode with individual pulses of the laser beam, wherein the individual pulses each have a fluence that is below a vaporization threshold fluence of the bleaching agent.