Abstract Streptococcus mutans (S. mutans) has been identified as a major etiologic agent of human dental caries and forms a significant proportion of oral streptococci in carious lesions. This study investigates the correlation of surface properties (effect of contact angle [CA] and free surface energy) on three restorative materials (zirconia, nickel–chromium–molybdenum alloy and composites) used in dental prosthetics with bacterial adhesion to S. mutans. Ten samples of each material (zirconia, nickel–chromium–molybdenum alloy and composites) of 8 mm diameter and 2.5 mm thickness were used. Aqueous CA measurements, free surface energy and bacterial adhesion to the sample surfaces were performed. Bacterial adhesion is determined by planting samples in the blood agar cultures and using an electron microscope (scanning electron microscopy [SEM]). The highest values of bacterial adhesion are found in composites, followed by the metal alloy, while the lowest values are observed in zirconia. Measurements show that zirconia has 17 bacteria; Ni–Cr–Mo alloy has 65, while the composite has 80 bacteria. The composites showed the highest degree of bacterial adhesion, compared to the other investigated materials, which correlates with the free surface energy of the samples (24.31 mJ/m2 for zirconia, 31.78 mJ/m2 for Ni–Cr–Mo alloy and 48.82 mJ/m2 for the composite).

中文翻译：

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各种牙科陶瓷中变形链球菌细菌粘附的研究：体外研究

摘要 变形链球菌 (S. mutans) 已被确定为人类龋齿的主要病原体，并在龋齿病变中形成相当大比例的口腔链球菌。本研究调查了三种修复材料（氧化锆、镍铬钼合金和复合材料）的表面特性（接触角 [CA] 和自由表面能的影响）与细菌粘附在变形链球菌上的假牙的相关性。使用直径为 8 毫米、厚度为 2.5 毫米的每种材料（氧化锆、镍-铬-钼合金和复合材料）的 10 个样品。进行了水性 CA 测量、自由表面能和细菌对样品表面的粘附。通过在血琼脂培养物中种植样品并使用电子显微镜（扫描电子显微镜 [SEM]）确定细菌粘附。在复合材料中发现细菌粘附的最高值，其次是金属合金，而在氧化锆中观察到最低值。测量显示氧化锆有17种细菌；Ni-Cr-Mo 合金有 65 个细菌，而复合材料有 80 个细菌。与其他研究材料相比，复合材料显示出最高程度的细菌粘附，这与样品的自由表面能相关（氧化锆为 24.31 mJ/m2，Ni-Cr-Mo 合金为 31.78 mJ/m2 和 48.82 mJ/m2 m2 为复合材料）。