Abstract：
A wide variety of microorganisms have been closely linked to metal corrosion in the form of adherent surface biofilms. Biofilms allow the development and maintenance of locally corrosive environments and/or permit direct corrosion including pitting corrosion. The presence of numerous genetically distinct microorganisms in the oral environment poses a threat to the integrity and durability of the surface of metallic prostheses and implants used in routine dentistry. However, the association between oral microorganisms and specific corrosion mechanisms is not clear. It is of practical importance to understand how microbial corrosion occurs and the associated risks to metallic materials in the oral environment. This knowledge is also important for researchers and clinicians who are increasingly concerned about the biological activity of the released corrosion products. Accordingly, the main goal was to comprehensively review the current literature regarding oral microbiologically influenced corrosion (MIC) including characteristics of biofilms and of the oral environment, MIC mechanisms, corrosion behavior in the presence of oral microorganisms and potentially mitigating technologies. Findings included that oral MIC has been ascribed mostly to aggressive metabolites secreted during microbial metabolism (metabolite-mediated MIC). However, from a thermodynamic point of view, extracellular electron transfer mechanisms (EET-MIC) through pili or electron transfer compounds cannot be ruled out. Various MIC mitigating methods have been demonstrated to be effective in short term, but long term evaluations are necessary before clinical applications can be considered. Currently most in-vitro studies fail to simulate the complexity of intraoral physiological conditions which may either reduce or exacerbate corrosion risk, which must be addressed in future studies. STATEMENT OF SIGNIFICANCE: A thorough analysis on literature regarding oral MIC (microbiologically influenced corrosion) of biomedical metallic materials has been carried out, including characteristics of oral environment, MIC mechanisms, corrosion behaviors in the presence of typical oral microorganisms and potential mitigating methods (materials design and surface design). There is currently a lack of mechanistic understanding of oral MIC which is very important not only to corrosion researchers but also to dentists and clinicians. This paper discusses the significance of biofilms from a biocorrosion perspective and summarizes several aspects of MIC mechanisms which could be caused by oral microorganisms. Oral MIC has been closely associated with not only the materials research but also the dental/clinical research fields in this work.
摘要：
各种各样的微生物以粘附的表面生物膜的形式与金属腐蚀密切相关。生物膜允许局部腐蚀性环境的发展和维持和/或允许包括点蚀在内的直接腐蚀。口腔环境中许多遗传上不同的微生物的存在对常规牙科中使用的金属假体和植入物的表面的完整性和耐久性构成威胁。然而,口腔微生物与特定腐蚀机制之间的关联尚不清楚。了解口腔环境中微生物腐蚀的发生方式以及金属材料的相关风险具有实际意义。这些知识对于越来越关注释放的腐蚀产物的生物活性的研究人员和临床医生也很重要。因此，主要目标是全面回顾目前有关口腔微生物影响腐蚀（MIC）的文献，包括生物膜和口腔环境的特征，MIC机制，在口腔微生物和潜在缓解技术存在下的腐蚀行为。发现包括口服MIC主要归因于微生物代谢过程中分泌的侵袭性代谢物（代谢物介导的MIC）。然而,从热力学的角度来看，不能排除通过菌毛或电子转移化合物的细胞外电子转移机制（EET-MIC）。各种减少MIC的方法已被证明是有效的在短期内，但是在考虑临床应用之前，需要进行长期评估。目前，大多数体外研究未能模拟口腔内生理条件的复杂性，这些条件可能会降低或加剧腐蚀风险，这必须在未来的研究中解决。重要性声明：对有关生物医学金属材料的口腔MIC（微生物影响的腐蚀）的文献进行了彻底的分析，包括口腔环境的特点，MIC机制，在存在典型口腔微生物和潜在缓解方法（材料设计和表面设计）的情况下的腐蚀行为。目前缺乏对口腔MIC的机械理解，这不仅对腐蚀研究人员而且对牙医和临床医生都非常重要。本文从生物腐蚀的角度讨论了生物膜的意义，并总结了口腔微生物可能引起的MIC机制的几个方面。在这项工作中，口腔MIC不仅与材料研究密切相关，而且与牙科/临床研究领域密切相关。
