在牙面上自然形成的牙菌斑一方面有致龋和致牙周病的作用,但另一方面又作为宿主防御机制的一部分,阻碍外源性微生物在口腔内定居。尽管牙菌斑微生态环境时有轻微的变化,但其细菌的组成却是相对稳定的,这种稳定性部分归因于细菌共生和拮抗作用之间的动态平衡。在某些情况下,微生态平衡会被打破,致使易感部位发病。如经常摄入可发酵的碳水化合物或唾液流量减少,将引起变形链球菌、乳杆菌、韦永氏 Dental plaque, which is naturally formed on the tooth surface, has cariogenic and periodontal causes on the one hand, and on the other hand, hinder the colonization of exogenous microorganisms in the oral cavity as part of the host defense mechanism. Although there is a slight change in the micro-ecological environment of the plaque, the bacterial composition is relatively stable, which is attributed in part to the dynamic balance between bacterial symbiosis and antagonism. In some cases, the micro-ecological balance will be broken, resulting in susceptible parts of the disease. Such as regular intake of fermentable carbohydrates or saliva flow reduction will cause mutans Streptococcus, Lactobacillus, Wei Yong's