Affiliations: Graduate School of Science and Engineering, Tokyo Denki University, Ishizaka, Hatoyama, Hiki, Saitama 350-0394, Japan | Department of Mechanical Engineering, Ibaraki University, 4-12-1, Nakanarusawa, Hitachi, Ibaraki 316-8511, Japan | International Apatite Co. Ltd., 3-20, Ogawamachi, Kanda, Sendagaya, Tokyo, 104-0031, Japan
Abstract: Hydroxyapatite (HA)/Hydrogen Peroxide (H2O2) solutions was prepared for a tooth whitening application. HA powder was immersed in the 100, 1000 and 10 000 ppm of the H2O2 solutions. The HA/H2O2, HA and H2O2 solutions were applied to HA discs and extracted teeth for weight and whiteness change evaluation. After 24 hours, each HA disc was measured for the weight changes and each tooth was measured for the whitening changes (L*) using a Spectro Color Meter. The topology of the teeth surfaces were also observed using Scanning Electron Microscope (SEM). The weight of the HA disc applied with H2O2 at all concentrations was lower than that applied with HA and HA/H2O2 solutions. The whiteness of the teeth treated with HA/H2O2 were higher than that treated with HA and H2O2 only solutions. The whiteness change of the teeth treated with the HA/H2O2 (10 000 ppm) showed the highest value in all solutions at L*=4.98±0.90 (p<0.05). In the SEM observation, the teeth surface treated with the H2O2 showed rough and destructive holes on the enamel surface. However, the teeth surface treated with the HA/H2O2 show smooth enamel surface due to covering of the destructive holes with HA powder.
