An attempt was made to determine the maximum amount of laser energy which could be utilized without impairing pulpal vitality. Forty rat molar teeth were irradiated in vivo; the Sharplan CO2 laser modality, focused to a 0.2‐mm‐diameter spot size was used. The energy output was varied by changing the power and/or the pulse duration. Subsequent histological examination of the irradiated teeth showed that the duration of exposure was more significant than the power. A pulse of 0.2 sec/10 W appears to be the safety limit in preserving pulpal vitality.
- tooth pulp