[Lasers in dentistry 3. The use of lasers for the prevention of dental caries].

Studies in our laboratories have demonstrated that specifically chosen CO2 laser treatment of dental enamel can markedly inhibit subsequent caries-like progression compared to controls in a laboratory model. Optimum caries inhibition in enamel appears to be achieved by pretreatments that produce surface temperatures in the range of 800-1200 degrees C. For clinical application the surface enamel heating must not lead to consequent pulp chamber temperature rises of > 4 degrees C. To meet these conditions a pulsed laser is required with a sufficiently high absorption coefficient (wavelength = 9.3 or 9.6 microns), pulse duration of 5-100 microseconds, 10-25 pulses per spot, repetition rate of 10-30 pulses per second, and low but effective fluence (approximately 1-5 J/cm2/pulse). A human intra-oral study has confirmed inhibition of caries progression in the human mouth. The clinical potential is good for caries preventive treatments by specific carbon dioxide laser conditions.