Pulpal temperature changes during low-power hard-tissue CO2 laser procedures.

Thermal insult to pulpal tissue is recognized as a major limitation to the use of lasers for dental hard-tissue procedures. This study examined thermal changes at the level of the dental pulp in human molar teeth irradiated with a CO2 dental laser using a pulsed mode of operation. Sectioned molar teeth were exposed, in vitro, to CO2 laser radiation. The laser parameters were those used clinically for laser desensitization and laser-enhanced fluoride treatment. Fissure regions and root surfaces were irradiated. For settings which might reasonably be used clinically, the temperature rise was not of a magnitude which would be expected to cause pulpal inflammation or necrosis. With regard to thermal properties of tooth structure, times taken to reach the maximum temperature reduced, and times taken to cool to baseline increased with increasing laser exposures.