Effect of the CO₂ laser (9.6 μm) on the dental pulp in humans

There has been great interest in the potential use of a laser to replace the dental handpiece (drill). Ideally a laser emitting radiation that is absorbed strongly by both the water and hydroxyapitite in teeth, would be a more efficient laser. Previous investigators showed that the 9.3 and 9.6 micron wavelength bands of the CO₂ laser contain hydroxyapitite absorption peaks. For this study, human patients who were to have teeth removed for either orthodontic or periodontal reasons were used. A total of 16 teeth were irradiated. The number of teeth treated per patient varied from 1-4. The laser used was a prototype CO₂ laser (ESC Medical Systems, Yokneam, Israel). The CO₂ laser emits 50 mJ 60 μsec-long pulses of 9.6 μm radiation in a beam focused to a 300 μm diameter (i/e²) spot. The pulps in both the laser and handpiece prepared holes appeared similar and had no apparent inflammation or vascular changes. It appears from this small sample of laser treated human teeth that this laser has an equal effect to the dental pulpal tissue when compared to the dental handpiece.