Tuning a laser wavelength to a stretching vibration of specific biomolecules, has some advantages for ablation of hard tissue and surface modification induced by photothermal or photo-mechanical interaction. In this paper, a tunable, pulsed, TEA CO2 laser was used to lase 9.45μm, which is the stretching vibration of phosphoric acid in hydroxyapatite. Dried cow dentine was irradiated to the CO2 laser of 36W/cm2. As results, laser irradiation shortened the peak wavelength of the dentine surface from 9.76μm to 8.93μm. The atomic ratio of Ca/P was changed from 1.4 to 1.9. These results showed the potential ability of a 9.45μm CO2 laser for ablating and modification of the dentine surface.
