Effects of a Semiconductor Laser on Pulp Temperature Sensitivity Threshold Level and Dentin Hypersensitivity

Abstract

There are various symptoms in dentin hypersensitivity, and various treatments have been carried out. Although newly developed semiconductor laser devices are expected to be used in clinical applications, the possible mechanisms of their anesthetic effect are still unclear. We therefore examined the effects of Nd:YAG laser irradiation in terms of hypersensitivity and dental pulp hemodynamics.
Twenty volunteers (10 males and 10 females, mean age 30.0±3.9 and 27.3±1.6 years, respectively), participated in the study. Both sides of healthy mandibular canines were selected as the experimental site: the right cervical surface was the irradiated site, and the left cervical surface was the control site without irradiation. Eleven teeth with dentin hypersensitivity were used in this study. A pulsed semiconductor laser was applied to the area twice for 30 seconds each, at 1 W, RPT 3 ms, duty 10%.
On both the control side and the irradiation side, pulp temperature sensitivity threshold level was measured by an electrothermal stimulator, the probe tip of which could be heated from 30°C to 65°C. A statistically significant increase in the pulp threshold level was observed in males after irradiation (p<0.05).
The severity of pain was evaluated by McGill Pain Questionnaire (MPQ), and there was a statistically significant decrease in the MPQ score after irradiation.
These results suggest that semiconductor laser irradiation is useful for dentin hypersensitivity.