University of Manchester Dental School, Oxford Road, Manchester, UK.
Dental Materials, Paris Descartes University, Paris, France.
Br Dent J. 2019 Feb;226(4):271-276. doi: 10.1038/s41415-019-0011-6.
Introduction EU council directive 2011/84/EU resulted in a demand for over the counter (OTC) bleaching products. The industry has latched onto this renewed demand by developing a range of non-hydrogen peroxide OTC products. Aims To determine whether non-hydrogen peroxide OTC whitening products available in the UK are safe and to determine the lightening effect of those products. Materials and methods A total of 21 extracted teeth (11 incisors and ten premolars) were collected and stored in chloramine-T solution. Five days before the study, all teeth were immersed in 5 ml of a standard green tea solution at room temperature (22±2 °C). Roots were sectioned from the teeth and cleaned using an ultrasonic bath. Teeth were then embedded in epoxy resin and sectioned inciso-gingivally to serve as paired test and control specimens. A positive control of 10% carbamide peroxide was used while saline was used as a negative control. Five OTC products were selected from two major British consumer outlets. Initially, products were applied to the teeth samples for two one-hour cycles, followed by the equivalent of one-week's application, according to the manufacturer's instruction. Samples were stored overnight in saline to minimise any effects of dehydration. Shades of teeth were taken blindly by a single trained clinician in a natural light environment against a grey background before and after application of the products. Vickers microhardness tests and scanning electron microscopy (SEM) analysis were undertaken. Results SEM analysis showed surface morphology alterations to varying degrees, with several samples demonstrating a distinct etching pattern post-exposure to the OTC products. Sample three ('Brilliant 5 minute kit') and sample five ('iWhite instant teeth whitening') produced the most extensive surface alterations. Samples three and five also resulted in a significant reduction (p = 0.008) in Vickers microhardness. Two OTC products resulted in a lightening effect less than the negative control saline, whereas two other OTC products resulted in a lightening effect greater than carbamide peroxide. Conclusion This study suggests that non-hydrogen peroxide OTC products have the potential to damage enamel and lighten teeth. The lightening effect of the OTC products is variable, however, it is most likely to occur in sodium chlorite based products.
简介
欧盟理事会指令 2011/84/EU 导致了对非处方（OTC）漂白产品的需求。该行业通过开发一系列非过氧化氢 OTC 产品抓住了这一需求。
目的
确定在英国销售的非过氧化氢 OTC 美白产品是否安全，并确定这些产品的美白效果。
材料和方法
共收集了 21 颗离体牙（11 颗切牙和 10 颗前磨牙），并储存在氯胺-T 溶液中。在研究前 5 天，所有牙齿都在室温（22±2°C）下浸泡在 5ml 标准绿茶溶液中。从牙齿上切下根部，并用超声波浴清洗。然后将牙齿嵌入环氧树脂中，并进行龈切向切片，作为配对的测试和对照标本。使用 10%的尿素过氧化氢作为阳性对照，而生理盐水作为阴性对照。从两个主要的英国消费者渠道中选择了 5 种 OTC 产品。最初，根据制造商的说明，产品应用于牙齿样本两个小时的循环，然后是相当于一周的应用。样本在盐水中储存过夜，以最大限度地减少任何脱水的影响。在应用产品前后，由一名经过培训的临床医生在自然光环境下对灰色背景下的牙齿进行盲色测试。进行了维氏显微硬度测试和扫描电子显微镜（SEM）分析。
结果
SEM 分析显示表面形态发生了不同程度的改变，有几个样本在暴露于 OTC 产品后表现出明显的蚀刻模式。样本三（“Brilliant 5 分钟套装”）和样本五（“iWhite 即时牙齿美白”）产生了最广泛的表面改变。样本三和样本五也导致维氏显微硬度显著降低（p=0.008）。两种 OTC 产品的美白效果小于阴性对照生理盐水，而另外两种 OTC 产品的美白效果大于尿素过氧化氢。
结论
本研究表明，非过氧化氢 OTC 产品具有损伤牙釉质和美白牙齿的潜力。然而，OTC 产品的美白效果是可变的，最有可能发生在基于次氯酸钠的产品中。
