Palacios Teresa, Tarancón Sandra, Pastor José Ygnacio
Department of Geological and Mining Engineering-CIME, Universidad Politécnica de Madrid, 28003 Madrid, Spain.
Department of Materials Science-CIME, Universidad Politécnica de Madrid, 28040 Madrid, Spain.
Polymers (Basel). 2022 Aug 10;14(16):3252. doi: 10.3390/polym14163252.
Two hybrid dental materials available for computer-aided design and manufacturing (CAD/CAM) dental restorations have been selected to explore their potential. On the one hand, the scarcely investigated polymer-based material Vita Enamic (VE) and, on the other hand, the leucite-based material IPS Empress CAD (EC). Their micro-structure and mechanical performance were analyzed in two environments: directly as received by the manufacturer (AR), and after immersion and storage in artificial saliva (AS) for 30 days to determine the influence of the saliva effect. To avoid an inappropriate selection of materials for clinical use, a full understanding of their mechanical behavior is essential. Therefore, this investigation aims to determine the micro-structural and chemical composition by field emission scanning electron microscopy (FE-SEM) and X-ray fluorescence analysis, establishing the density, micro- and nano-hardness, the nano-elastic modulus, and the flexural strength and fracture toughness (by introducing a femto-laser notch to replicate a real crack). In addition, fracture surfaces of the broken samples were analyzed to correlate the failure micro-mechanisms with their mechanical properties. Results indicate that while the crystalline phase of the materials is very similar (composed of SiO and AlO), the micro-structure and mechanical behavior is not. The material EC, with finer micro-structure, exhibits a higher mechanical performance but with greater variability of results. Furthermore, the material VE, with a 25 vol.% polymer phase, shows a mechanical performance similar to enamel and dentin and therefore more similar to human behavior.
已选择两种可用于计算机辅助设计和制造（CAD/CAM）牙科修复体的混合牙科材料来探索其潜力。一方面，是研究较少的基于聚合物的材料维他易美（VE），另一方面，是基于白榴石的材料义获嘉全瓷CAD（EC）。在两种环境下分析了它们的微观结构和机械性能：直接采用制造商提供的原样（AR），以及在人工唾液（AS）中浸泡和储存30天后，以确定唾液影响。为避免临床使用时材料选择不当，全面了解其机械行为至关重要。因此，本研究旨在通过场发射扫描电子显微镜（FE-SEM）和X射线荧光分析确定微观结构和化学成分，测定密度、微硬度和纳米硬度、纳米弹性模量以及弯曲强度和断裂韧性（通过引入飞秒激光切口来模拟真实裂纹）。此外，对断裂样品的断口表面进行分析，以将失效微观机制与其机械性能相关联。结果表明，虽然材料的晶相非常相似（由SiO和AlO组成），但其微观结构和机械行为并不相同。具有更精细微观结构的材料EC表现出更高的机械性能，但结果的变异性更大。此外，具有25体积%聚合物相的材料VE表现出与牙釉质和牙本质相似的机械性能，因此更接近人体行为。
