Hintz J K, Bradley T G, Eliades T
Division of Orthodontics, School of Dentistry, Marquette University, Milwaukee, Wisconsin, USA.
Eur J Orthod. 2001 Aug;23(4):411-5. doi: 10.1093/ejo/23.4.411.
The purpose of this study was to determine if a colour difference exists between teeth that had orthodontic appliances bonded to and debonded from them and untreated controls subjected to whitening with 10 per cent carbamide peroxide. The sample consisted of 20 pairs of first and second premolars extracted for orthodontic reasons. The contralateral surfaces were divided into an experimental and control group. The experimental group underwent orthodontic bonding/debonding procedures. Both groups were subjected to 4 hour whitening and 20 hour hydration sessions for 30 days. The Lab* colour system was chosen to evaluate any colour change and these changes were calculated by determining the delta E from the Lab* values using a colorimeter. Colour change readings were taken before and after each 4 hour whitening. Additional readings were taken at 48 hour intervals for 30 days following the cessation of active whitening. The results were analysed using statistical (ANOVA) and graphical analyses (alpha = 0.05). A colour change difference of 2 CIELAB units was set as being clinically significant. A mean clinical colour difference was found for enamel surfaces subjected to orthodontic bonding/debonding of attachments relative to control sites after whitening. Bonding and debonding procedures resulted in a significant colour difference between orthodontic bonded and control sites at the end of the active period, which became insignificant at the end of the 30 day period of monitoring. Both the control and debonded sites responded to whitening; however, the control sites responded initially to a greater extent; the orthodontic debonded sites did not respond until after 2 weeks of continuous whitening. After the 2 week period the improved response of the debonded sites decreased the colour difference between the two groups.
本研究的目的是确定粘结过正畸矫治器并脱除矫治器的牙齿与未经处理、用10%过氧化脲美白的对照牙齿之间是否存在颜色差异。样本包括因正畸原因拔除的20对第一和第二前磨牙。将对侧牙面分为实验组和对照组。实验组接受正畸粘结/脱除程序。两组均进行为期30天、每次4小时的美白和20小时的水合处理。选择Lab颜色系统评估任何颜色变化，并使用色度计通过确定Lab值的色差值（ΔE）来计算这些变化。在每次4小时美白前后进行颜色变化读数。在积极美白停止后的30天内，每隔48小时进行额外读数。结果采用统计学分析（方差分析）和图形分析（α = 0.05）。将2个CIELAB单位的颜色变化差异设定为具有临床意义。发现与对照部位相比，接受正畸附件粘结/脱除的牙釉质表面在美白后存在平均临床颜色差异。粘结和脱除程序在美白活跃期结束时导致正畸粘结部位和对照部位之间存在显著颜色差异，而在30天监测期结束时这种差异变得不显著。对照部位和脱除矫治器的部位对美白均有反应；然而，对照部位最初的反应程度更大；正畸脱除矫治器的部位直到连续美白2周后才有反应。在2周期间之后，脱除矫治器部位的反应改善使两组之间的颜色差异减小。
