The effects of laser radiation on teeth, dental pulp, and oral mucosa of experimental animals

Twelve Syrian hamsters received 35 and 55 joule dosages of laser radiation, focused on the mandibular incisor and the lateral border of the tongue. Cavitation was produced in the enamel and dentine. Adjacent to the cavitation, normal-appearing enamel was replaced by a chalky white, amorphous substance in the 35 joule applications and by a smooth, glassy substance in the 55 joule applications. Reflected energy produced visible but less severe changes in the enamel of adjacent mandibular and maxillary incisors. Severe degenerative changes occurred in the dental pulps of irradiated incisors. Less severe pulpal degeneration was noted in the molar teeth at some distance from the laser focal point.