Computer monitoring of the thermal effects induced by Er:YAG laser radiation during preparation of the hard tooth tissue

We are presenting the results of the thermal changes of enamel, dentin and pulp temperature monitoring in extracted human teeth subjected to a pulsed Er:YAG laser radiation. We made a series of experiments irradiating the tooth using the pulsed Er:YAG laser and monitoring simultaneously the temperature of various parts of the tooth. The temperature was measured by the bead thermistor either in contact with the tooth surface or built in the pulp chamber. In the former experiments it was demonstrated, that the uncooled preparation can cause irreversible changes of the pulp. In the second part of the experiments the teeth have been cooled by flowing water. During the laser preparation of the enamel and the dentin the temperature did not increase more than 2 degree(s)C. In the moment of dentin perforation and hence laser irradiation of the pulp, the pulp temperature increased rapidly. The opening of the pulp coincides with the rapid temperature increase. These studies verified the feasibility of the pulsed Erbium:YAG laser use in stomatology.