Abstract：
Aims - to compare the color changes, the surface roughness and morphology of the enamel bleached with two different bleaching solutions (chemical and laser activated), preceded or not with acid etching. Thirty teeth of bovine prepared and haphazardly assigned to 2 groups (n=15) depending on bleaching technique. Each group subdivided to 3 subgroup (n=5) consistent with acid etching by 37% phosphoric acid. Atomic force microscopy and VITA easy shade spectrophotometer were performed twice for all the specimens before and after bleaching. ANOVA, the Paired sample t-test, and the independent sample t-test used for statistical analysis. As for the color changes, the groups that were bleached by the chemical method, the difference among the three subgroups was statistically significant. This also applies to the groups bleached with the laser method. When comparing the results of the chemical bleaching subgroups with the laser bleaching ones, the difference was not significant. Roughness results showed significant differences between certain subgroups and non-significant differences among others. However, the difference was statistically significant between the chemical and laser groups, laser technique resulted in less surface roughness than the chemical one. Acid etching before bleaching produced better colour change in both the chemical and laser assisted bleaching. In chemical bleaching, surface roughness was higher when acid etching was used. This was also true for laser bleaching technique. In general, laser assisted bleaching produced less surface roughness than chemical bleaching.
摘要：
目的-比较颜色的变化，用两种不同的漂白溶液（化学和激光活化）漂白的釉质的表面粗糙度和形态，在酸蚀刻之前或不在酸蚀刻之前。根据漂白技术，准备了30颗牛齿，并随意分配给2组（n=15）。每组细分为3个亚组（n=5），与37％磷酸的酸蚀刻一致。对漂白前后的所有样品进行两次原子力显微镜和VITA简易阴影分光光度计。方差分析,配对样本t检验，统计学分析采用独立样本t检验。至于颜色的变化，用化学方法漂白的群体，三个亚组之间的差异有统计学意义。这也适用于用激光方法漂白的基团。当比较化学漂白亚组和激光漂白亚组的结果时，差异不显著。粗糙度结果显示，某些亚组之间存在显着差异，而其他亚组之间则不存在显着差异。然而,化学组和激光组之间的差异有统计学意义，激光技术的表面粗糙度比化学技术小。漂白之前的酸蚀刻在化学和激光辅助漂白中均产生更好的颜色变化。在化学漂白中，当使用酸蚀刻时，表面粗糙度较高。对于激光漂白技术也是如此。总的来说,激光辅助漂白比化学漂白产生更小的表面粗糙度。
