Ma Xiao, Jiang Tao, Sun Lili, Wang Zhejun, Zhou Yi, Wang Yining
Key Laboratory for Oral Biomedical Engineering, Ministry of Education, School and Hospital of Stomatology, Wuhan University, 237 Luoyu Road, Wuhan 430079, PR China.
Am J Dent. 2009 Dec;22(6):324-8.
To investigate the changes in color and translucency properties of enamel following 14 days treatment with carbamide peroxide.
24 extracted premolars were used in this study. Two enamel-dentin specimens were prepared from each tooth and randomly assigned to be bleached with carbamide peroxide for 14 days or stored in artificial saliva as control. A spectrophotometer (Spectrascan PR650) was employed to measure the color of specimens according to the CIELab system. Color measurement of enamel-dentin specimens was performed prior to and after bleaching. After 14 days bleaching, enamel slabs were prepared by removing dentin parts using a low-speed saw. Then the color and translucency parameter (TP) of enamel slabs was measured over a black and a white background. Data between the experimental group and the control group were analyzed by paired t-test.
After bleaching, the color of enamel slabs and controls differed significantly both over the black and white background in L* and b* values (all P < 0.001). The translucency parameter (TP) of bleached enamel slabs was significantly lower than that of controls (P < 0.01). Both the deltaE values of enamel on the two backgrounds were significantly correlated to that of enamel-dentin specimens (P = 0.003; P = 0.012).
研究过氧化物脲处理14天后牙釉质颜色和透明度特性的变化。
本研究使用24颗拔除的前磨牙。从每颗牙齿制备两个牙釉质-牙本质标本，并随机分为用过氧化物脲漂白14天或储存在人工唾液中作为对照。使用分光光度计（Spectrascan PR650）根据CIELab系统测量标本的颜色。在漂白前后对牙釉质-牙本质标本进行颜色测量。漂白14天后，使用低速锯去除牙本质部分制备牙釉质片。然后在黑色和白色背景上测量牙釉质片的颜色和透明度参数（TP）。通过配对t检验分析实验组和对照组之间的数据。
漂白后，牙釉质片和对照组在黑色和白色背景上的L和b值均有显著差异（所有P < 0.001）。漂白牙釉质片的透明度参数（TP）显著低于对照组（P < 0.01）。两种背景下牙釉质的ΔE值均与牙釉质-牙本质标本的ΔE值显著相关（P = 0.003；P = 0.012）。
