Porojan Liliana, Toma Flavia Roxana, Gherban Mihaela Ionela, Vasiliu Roxana Diana, Matichescu Anamaria
Department of Dental Prostheses Technology (Dental Technology), Center for Advanced Technologies in Dental Prosthodontics, Faculty of Dental Medicine, "Victor Babeș" University of Medicine and Pharmacy Timișoara, Eftimie Murgu Sq. No. 2, 300041 Timisoara, Romania.
National Institute for Research and Development in Electrochemistry and Condensed Matter, 300569 Timisoara, Romania.
Biomimetics (Basel). 2024 Jun 23;9(7):379. doi: 10.3390/biomimetics9070379.
(1) Background: PETG (polyethylene terephthalate glycol) is a transparent, inexpensive, and versatile thermoplastic biomaterial, and it is increasingly being used for a variety of medical applications in dentistry, orthopedics, tissue engineering, and surgery. It is known to have remarkable properties such as tensile strength, high ductility, and resistance to chemical insults and heat, but it can be affected by various environmental conditions. The aim of the present study was to evaluate the topographical characteristics of four thermoplastic dental appliance materials in relation to water sorption in simulated oral environments (artificial saliva samples with different pH values). (2) Methods: The following four types of PETG clear thermoplastic materials were selected for the present study: Leone (L), Crystal (C), Erkodur (E), and Duran (D). In relation to the desiccation and water-uptake stages, their water sorption (Wsp) and solubility (Wsl) were calculated, and the surface topographies were analyzed on two length scales. The surface roughness was determined using a contact profilometer, and nanoroughness measurements were generated by three-dimensional profiles using an atomic force microscope (AFM). Statistical analyses (one-way ANOVA and unpaired and paired Student -tests) were performed. (3) Results: After saliva immersion, the weights of all samples increased, and the highest sorption was recorded in a basic environment. Among the materials, the water uptake for the L samples was the highest, and for E, it was the lowest. In relation to water solubility, significant values were registered for both the L and C samples' materials. After immersion and desiccation, a decreasing trend in microroughness was observed. The AFM high-resolution images reflected more irregular surfaces related to saliva immersion. (4) Conclusions: The sorption rates recorded in water-based artificial saliva were higher for basic pH levels, with significant differences between the samples. There were also significant differences related to the behaviors of the materials included in the study. In relation to roughness, on a microscale, the surfaces tended to be smoother after the saliva immersions, and on a nanoscale, they became more irregular.
(1) 背景：聚对苯二甲酸乙二醇酯（PETG）是一种透明、廉价且用途广泛的热塑性生物材料，越来越多地用于牙科、骨科、组织工程和外科手术等各种医学应用中。已知它具有诸如拉伸强度、高延展性以及耐化学侵蚀和耐热等显著特性，但它会受到各种环境条件的影响。本研究的目的是评估四种热塑性牙科矫治器材料在模拟口腔环境（不同pH值的人工唾液样本）中与吸水相关的表面形貌特征。(2) 方法：本研究选择了以下四种类型的PETG透明热塑性材料：莱昂内（L）、水晶（C）、埃尔科杜尔（E）和杜兰（D）。针对干燥和吸水阶段，计算了它们的吸水率（Wsp）和溶解度（Wsl），并在两个长度尺度上分析了表面形貌。使用接触式轮廓仪测定表面粗糙度，并使用原子力显微镜（AFM）通过三维轮廓生成纳米粗糙度测量值。进行了统计分析（单因素方差分析以及不成对和成对学生t检验）。(3) 结果：唾液浸泡后，所有样本的重量均增加，在碱性环境中记录到最高的吸水量。在这些材料中，L样本的吸水量最高，E样本的吸水量最低。关于水溶性，L和C样本材料均记录到显著值。浸泡和干燥后，观察到微观粗糙度呈下降趋势。AFM高分辨率图像反映出与唾液浸泡相关的更不规则表面。(4) 结论：在水基人工唾液中记录的碱性pH水平的吸附率更高，样本之间存在显著差异。本研究中所包含材料的行为也存在显著差异。关于粗糙度，在微观尺度上，唾液浸泡后表面趋于更光滑，而在纳米尺度上，它们变得更加不规则。
