Oral mucosal disease (OMD), which is also called soft tissue oral disease, is described as a series of disorders or conditions affecting the mucosa and soft tissue in the oral cavity. Its etiology is unclear, but emerging evidence has implicated the influence of the composition of the oral mucosa and saliva-resident microbiota. In turn, this dysbiosis effects the immune response balance and epithelial barrier function, followed by the occurrence and progression of OMD. In addition, oral microbial dysbiosis is diverse in different types of diseases and different disease progressions, suggesting that key causal pathogens may exist in various oral pathologies. This narrative literature review primarily discusses the most recent findings focusing on how microbial dysbiosis communicates with mucosal adaptive immune cells and the epithelial barrier in the context of five representative OMDs, including oral candidiasis (OC), oral lichen planus (OLP), recurrent aphthous ulcer (RAU), oral leukoplakia (OLK), and oral squamous cell carcinoma (OSCC), to provide new insight into the pathogenetic mechanisms of OMDs.

口腔粘膜病（OMD），也称为软组织口腔疾病，被描述为影响口腔粘膜和软组织的一系列疾病或病症。其病因尚不清楚，但新出现的证据表明口腔粘膜和唾液微生物群组成的影响。反过来，这种生态失调会影响免疫反应平衡和上皮屏障功能，进而导致 OMD 的发生和发展。此外，口腔微生物失调在不同类型的疾病和不同的疾病进展中是不同的，这表明关键的致病病原体可能存在于各种口腔病变中。