Oral Health Prev Dent. 2021 Jan 26;19:7-14. doi: 10.3290/j.ohpd.b875523.
The aim of the present research was to analyse the effects of two bleaching agents, on the enamel crystallography by means of X-ray diffraction.
Twelve human sound posterior teeth, were collected for the present study (n = 12) and from each tooth two enamel slabs were obtained and randomly assigned to one of two different bleaching protocols. The first protocol involved an in-office bleaching agent (hydrogen peroxide 37.5%/ SDI Polaoffice+), and the second an at-home whitening product (carbamide peroxide 16%/ PHILIPS Zoom! NiteWhite). X-ray diffraction readings were made before and after applying the treatments in order to analyse the peak intensity and crystal domain size. Additionally, scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) were carried out to identify the composition correctly. Statistical analysis included repeated measures analysis of variance (p ≤ 0.05). Results: Peak intensity in spectra obtained by X-ray diffraction had a tendency to diminish, mostly in the at-home bleaching group. The analysed data approximate a decrease in the crystal domain size among the samples treated for longer periods of time. Statistical analysis depicted no statistically significant differences among the experimental groups (p ≥ 0.05). Conclusions: Crystal domain size had a tendency to decrease, mostly when the enamel was treated by bleaching gels that had to be applied by prolonged periods of time.
本研究旨在通过 X 射线衍射分析两种漂白剂对牙釉质结晶学的影响。
本研究共收集了 12 个人体健康的后牙（n=12），并从每个牙齿中获得了两个牙釉质薄片，并随机分配到两种不同的漂白方案之一。第一种方案涉及一种诊室用漂白剂（37.5%过氧化氢/ SDI Polaoffice+），第二种方案涉及一种家庭用美白产品（16%脲素/ PHILIPS Zoom! NiteWhite）。在应用治疗前后进行 X 射线衍射读数，以分析峰值强度和晶体畴大小。此外，还进行了扫描电子显微镜（SEM）和能谱（EDX）分析，以正确识别成分。统计分析包括重复测量方差分析（p≤0.05）。
X 射线衍射光谱中的峰值强度有减弱的趋势，主要发生在家用漂白组。分析数据表明，经过较长时间处理的样品中晶体畴大小呈下降趋势。实验组之间的统计分析无统计学差异（p≥0.05）。
晶体畴大小有减小的趋势，主要发生在用需要长时间应用的漂白凝胶处理牙釉质时。
