Tooth Whitening With Hydrogen Peroxide Assisted by a Direct-Current Cold Atmospheric-Pressure Air Plasma Microjet

A tooth-whitening process using hydrogen peroxide (H ₂ O ₂ ) enhanced by a direct-current cold atmospheric-pressure plasma microjet (PMJ) is presented. Compared with the conventional clinical method of using H ₂ O ₂ alone, a significant improvement of the tooth-whitening process was observed when the PMJ was used in the process. The tooth-surface temperature was monitored for safety considerations and did not exceed 37°C at a distance of 1 cm between the exit nozzle of the plasma source and the tooth for a treatment time of 20 min. No apparent differences in the tooth-surface morphology and microhardness were observed between teeth treated with and without the PMJ. The use of the PMJ with H ₂ O ₂ resulted in an enhanced production of reactive hydroxyl (OH) radicals. This plasma-enhanced tooth-whitening method may be a promising new method for clinical applications.