Laboratório de Instrumentação, Engenharia Biomédica e Física das Radiações, Campus Caparica, 2829-516 Caparica, Portugal; Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus Caparica, 2829-516 Caparica, Portugal.
Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus Caparica, 2829-516 Caparica, Portugal.
Spectrochim Acta A Mol Biomol Spectrosc. 2020 Aug 5;236:118378. doi: 10.1016/j.saa.2020.118378. Epub 2020 Apr 16.
In this in vitro study, the effect of the application of tooth bleaching products in human enamel was evaluated using polarized Raman microscopy, particle induced gamma-ray emission (PIGE) and Vickers Hardness test. Due to their acidic nature, teeth whitening products are associated with changes in enamel mineralization. Consequently, products have appeared in the market that promote the incorporation of fluorine in order to decrease the solubility of the hydroxyapatite in enamel and prevent demineralization. This way, four commercial products with different active principle concentrations: 16% carbamide peroxide (Opalescence PF® and VivaStyle®) or 6% hydrogen peroxide (Opalescence Go PF® and VivaStyle Paint On®) and presence or not of fluorine were compared. The information on the crystalline state of the enamel was provided by the determination of the depolarization ratio of the symmetric stretching band of phosphate (at 959 cm). Furthermore, the content and uptake of F was evaluated using PIGE in the two fluorinated products as well as in one negative control group. In order to evaluate the microhardness of enamel by means of Vickers test, another group of polished samples was prepared (using Opalescence PF®) and evaluated. Conversely to what could be expected, the obtained results determined a statistically significant decrease of depolarization ratio, leading to an increase of mineralization after the application of the bleaching products, except for VivaStyle®. For this group, no significant variation was obtained before-after treatment, most likely due to the acidity of the product (pH = 5.8). Additionally, an increase of concentration of F in the dental tissues was determined for the fluorinated products. On the other hand, enamel polishing, required for the application of the Vickers test, led to increased susceptibility to erosion, resulting in decreased hardness and an increased enamel depolarization ratio.
在这项体外研究中，使用偏光拉曼显微镜、粒子感生γ射线发射（PIGE）和维氏硬度测试评估了牙漂白产品在人牙釉质上的应用效果。由于牙漂白产品的酸性性质，它们与牙釉质矿化变化有关。因此，市场上出现了一些产品，这些产品促进了氟的掺入，以降低牙釉质中羟磷灰石的溶解度并防止脱矿。为此，比较了四种具有不同有效成分浓度的商业产品：16%的过氧化脲（Opalescence PF®和 VivaStyle®）或 6%的过氧化氢（Opalescence Go PF®和 VivaStyle Paint On®），以及是否含有氟。通过测定磷酸盐对称伸缩带的去偏振比（在 959 cm 处），提供了牙釉质结晶状态的信息。此外，使用 PIGE 评估了两种含氟产品以及一个阴性对照组中 F 的含量和摄取。为了通过维氏硬度测试评估牙釉质的显微硬度，制备了另一组抛光样品（使用 Opalescence PF®）并进行了评估。与预期相反，获得的结果确定了去偏振比的统计学显著降低，导致在应用漂白产品后矿化增加，除了 VivaStyle®之外。对于该组，处理前后未获得显著变化，最有可能是由于产品的酸性（pH=5.8）。此外，还确定了含氟产品中牙组织中 F 浓度的增加。另一方面，维氏硬度测试应用所需的牙釉质抛光导致侵蚀敏感性增加，导致硬度降低和牙釉质去偏振比增加。
