[Clinical study on the treatment of hypersensitive dentin by GaAlAs laser diode using the double blind test].

This study was conducted to evaluate the results of treating hypersensitive dentin with a GaAlAs semiconductor laser diode using the double blind test. For this purpose, sixty-seven teeth were examined. Thirty of the teeth were treated with laser irradiation (active group), while the other 36 were not (dummy group). The irradiation equipment was obtained from J. Morita Co. and operated at a continuous wavelength of 790 nm and a laser strength of 30 mW. The following results were obtained: After two hours of laser irradiation, 40% of the active group and 13.9% of the dummy group showed effective results. After one day, these values were 36.9% and 13.9%, and after 5 days, 43.3% and 19.4%, respectively. A overall evaluation indicated these values to be 60.0% and 22.2%, respectively. In evaluating these four results, significant differences are apparent between the active and dummy groups. The present results indicate that laser irradiation may possibly be effective in decreasing pain when treating hypersensitive dentin.