Bleaching of discolored teeth with high frequwmy current

Research Project

Project/Area Number	04671168
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	Conservative dentistry
Research Institution	SHOWA UNIVERSITY
Principal Investigator	HISAMITSU Hisashi Showa U, Orthodont. prof, 歯学部, 教授 (30092430)
Co-Investigator(Kenkyū-buntansha)	KOBAYASHI Noriko Showa U, Orthodont. Assistant, 歯学部, 助手 (10245805) MATSUBA Hiroshi Showa U, Orthodont. Assistant, 歯学部, 助手 (90241025) SUZUKI Toshimitsu Showa U, Orthodont. A.prof, 歯学部, 助教授 (80154558) 下村博昭和大学, 歯学部, 講師 (80196568)
Project Period (FY)	1992 – 1993
Project Status	Completed (Fiscal Year 1993)
Budget Amount *help	¥1,900,000 (Direct Cost: ¥1,900,000) Fiscal Year 1993: ¥500,000 (Direct Cost: ¥500,000) Fiscal Year 1992: ¥1,400,000 (Direct Cost: ¥1,400,000)
Keywords	discolored teeth / teeth bleaching / high requency current / hydrogen peroxide / 漂白 / 高周波 / 半波整流 / ヒト抜去歯 / 電気メス / 色差 / 酸処理
Research Abstract	From the results of the colre analyqer test, it was obvious that color of the surfoce brightened and the yellowish color was slightly gone after bleaching. The etching procedure decreased L* and b. However, the bleaching theatment resulted in a gradual incrase of L and decrease of b. The etching procedure rainforced the efficaay of bleaching. To compaire the four bleaching agents in dE, there was a signigificant difference only vetween H_2O_2 and Hi-Lite in the no-etching group. From the SEM observation, the micro struct of the enamel prisms were destroyed by the bkeaching procedune.The morphalogical chage of the enamel aurface by high frequwncy current was obserued. This new etching-bleaching method for discolored teeth using high frequency current was found to be effectiue and clinically safe.