de Marsillac Mirian de Waele Souchois, Vieira Ricardo de Sousa
Department of Community and Preventive Dentistry of Rio de Janeiro, Rio de Janeiro, Brazil.
Indian J Dent Res. 2013 Mar-Apr;24(2):249-54. doi: 10.4103/0970-9290.116699.
To assess through scanning electron microscopy (SEM) and cross-sectional microhardness (CSMH) test whether the methodology exposed in this experiment can be used to produce artificial active white spot lesions (AAWSLs) on smooth unabraded human dental enamel.
Ten human permanent molars were used in this experiment. One section of each tooth was double coated with nail varnish except for a limited central area sized 2.5 mm × 1 mm (2.5 mm 2 ). Each specimen was individually exposed to 10.4 ml of a demineralizing solution at pH 5.0, during 42 days (37°C) without agitation. Samples were sectioned in the center of the AAWSL and one half was analyzed in SEM and the other half was subjected to CSMH. Descriptive statistics was performed to determine mean depth of the lesion.
The mean depth of AAWSL was 100 μm (s.d. =12.1) and a white dull rough surface could be detected by the unaided eye. SEM images demonstrated that although some surface areas of the lesion appeared to be relatively intact, erosion was present. A prismatic pattern of dissolution was observed in all samples with an enlargement of the prism sheaths and some samples had also sites of destruction of prism cores.
This methodology can be used to induce AAWSLs in human dental enamel but surface erosion has to be taken into account when performing CSMH test.
通过扫描电子显微镜（SEM）和横断面显微硬度（CSMH）测试，评估本实验中所采用的方法是否可用于在未磨损的光滑人类牙釉质上产生人工活性白斑病变（AAWSLs）。
本实验使用了10颗人类恒牙。每颗牙齿的一个部分除了一个2.5毫米×1毫米（2.5平方毫米）的有限中央区域外，均用指甲油进行双层覆盖。每个样本单独暴露于10.4毫升pH值为5.0的脱矿溶液中，在42天内（37°C）不进行搅拌。在AAWSL的中心对样本进行切片，其中一半在SEM下进行分析，另一半进行CSMH测试。进行描述性统计以确定病变的平均深度。
AAWSL的平均深度为100微米（标准差=12.1），肉眼可检测到白色暗淡粗糙的表面。SEM图像显示，尽管病变的一些表面区域似乎相对完整，但存在侵蚀现象。在所有样本中均观察到棱柱形的溶解模式，棱柱鞘扩大，一些样本还出现了棱柱核心破坏的部位。
该方法可用于在人类牙釉质中诱导产生AAWSLs，但在进行CSMH测试时必须考虑表面侵蚀的问题。
