Kwon So Ran, Kurti Steven R, Oyoyo Udochukwu, Li Yiming
University of Iowa College of Dentistry and Dental Clinics, Iowa City, IA, USA.
Loma Linda University, Loma Linda, CA, USA.
Odontology. 2015 Sep;103(3):274-9. doi: 10.1007/s10266-014-0163-4. Epub 2014 Jun 28.
The purpose of this study was to evaluate the effect of four whitening modalities on surface enamel as assessed with microhardness tester, profilometer, and scanning electron microscopy (SEM). Whitening was performed according to manufacturer's directions for over-the-counter (OTC), dentist dispensed for home use (HW) and in-office (OW) whitening. Do-it-yourself (DIY) whitening consisted of a strawberry and baking soda mix. Additionally, negative and positive controls were used. A total of 120 enamel specimens were used for microhardness testing at baseline and post-whitening. Following microhardness testing specimens were prepared for SEM observations. A total of 120 enamel specimens were used for surface roughness testing at baseline and post-whitening (n = 20 per group). Rank-based Analysis of Covariance was performed to compare microhardness and surface roughness changes. Tests of hypotheses were two-sided with α = 0.05. There was a significant difference in Knoop hardness changes (ΔKHN) among the groups (Kruskal-Wallis test, p < 0.0001). Significant hardness reduction was observed in the positive control and DIY group (p < 0.0001). Mean surface roughness changes (ΔRa) were significantly different among the groups (Kruskal-Wallis test, p < 0.0001). Surface roughness increased in the OTC group (p = 0.03) and in the positive control (p < 0.0001). The four whitening modalities-DIY, OTC, HW and OW induced minimal surface morphology changes when observed with SEM. It can be concluded that none of the four whitening modalities adversely affected enamel surface morphology. However, caution should be advised when using a DIY regimen as it may affect enamel microhardness and an OTC product as it has the potential to increase surface roughness.
本研究的目的是通过显微硬度计、轮廓仪和扫描电子显微镜（SEM）评估四种美白方式对釉质表面的影响。美白按照非处方（OTC）、牙医处方家庭使用（HW）和诊室美白（OW）的制造商说明进行。自制（DIY）美白由草莓和小苏打混合物组成。此外，还使用了阴性和阳性对照。总共120个釉质标本用于基线和美白后的显微硬度测试。在显微硬度测试后，制备标本用于SEM观察。总共120个釉质标本用于基线和美白后的表面粗糙度测试（每组n = 20）。进行基于秩的协方差分析以比较显微硬度和表面粗糙度的变化。假设检验为双侧检验，α = 0.05。各组之间努氏硬度变化（ΔKHN）存在显著差异（Kruskal-Wallis检验，p < 0.0001）。在阳性对照和DIY组中观察到显著的硬度降低（p < 0.0001）。各组之间平均表面粗糙度变化（ΔRa）存在显著差异（Kruskal-Wallis检验，p < 0.0001）。OTC组（p = 0.03）和阳性对照组（p < 0.0001）的表面粗糙度增加。用SEM观察时，四种美白方式——DIY、OTC、HW和OW引起的表面形态变化最小。可以得出结论，四种美白方式均未对釉质表面形态产生不利影响。然而，使用DIY方案时应谨慎，因为它可能会影响釉质显微硬度；使用OTC产品时也应谨慎，因为它有可能增加表面粗糙度。
