关键词: 牙漂白, 光源, 过氧化氢, 比色仪, 牙敏感

Abstract:

Objective    To evaluate the clinical effectiveness of a light-activated bleaching system on vital teeth. Methods    Two hundred and six cases bleached by ‘Beyond’ light-activated bleaching system during three years were included in the study to evaluate the effectiveness. All the cases were divided into four groups：dental fluorosis，tetracycline stained teeth，extrinsic stained teeth and others. Visual determination of shade and spectrophotometer were used to measure the tooth discoloration immediately after bleaching. After twenty-four hours，one week and three months of follow-up，assess the rebound of color. Assessment of tooth sensitivity was carried out by visual analogue scale immediately，twenty four hours and one week after bleaching. Results    Satisfactory effectiveness was achieved in all groups except the group of tetracycline stained teeth. No obvious rebound of color was observed in the period of three months. Tooth sensitivity only occurred within twenty hours after bleaching. Except in the group of dental fluorosis，after 24 hours of bleaching tooth sensitivity in other groups had no difference （P > 0.05） compared with that before bleaching. The level of tooth sensitivity in group of dental fluorosis also recovered within one week. Conclusion    Stable and satisfactory effectiveness can be achieved in vital tooth bleaching by light-activated bleaching system.

Key words: tooth bleaching, light sources, hydrogen peroxide, spectrophotometer, tooth sensitivity