The oral microbiota is a dynamic, polymicrobial community that plays a critical role in health and disease. It consists of diverse microorganisms that inhabit distinct microenvironments in the oral cavity, such as the surfaces of teeth and mucosal membranes. These communities are regulated by host and environmental factors and are essential for maintaining homeostasis or causing dysbiosis, which can lead to diseases like dental caries and periodontitis. These diseases are driven by a feedforward loop between the microbiota and host factors, such as inflammation and dietary sugars, which favor the emergence and persistence of dysbiosis. The oral microbiota is composed of a variety of bacteria, including streptococci and actinomyces, which are primary colonizers of oral surfaces. As the subgingival area becomes more anaerobic, the microbial composition shifts to include more strict anaerobes. The spatial and structural organization of microbial communities is also essential for physical and metabolic interactions that can be antagonistic or cooperative. In dental caries, overexposure to dietary carbohydrates and host factors promotes the production of extracellular polymeric substances (EPS) and acidic metabolites, leading to the accumulation of acidogenic and acidic microorganisms. This can result in the formation of a pathogenic biofilm that can cause caries. In periodontal disease, polymicrobial communities induce a dysregulated and destructive host response through a mechanism called polymicrobial synergy and dysbiosis. The microbiota associated with periodontal disease is influenced by 'specialist' microorganisms that possess metabolic functions and an elevated virulence potential. The oral microbiota is also associated with systemic diseases such as oral cancers and rheumatoid arthritis. The concept of polymicrobial synergy is central to understanding the pathogenesis of oral diseases, as microorganisms often interact synergistically to enhance colonization, persistence, or pathogenicity. The role of the extracellular matrix in the biofilm lifestyle is increasingly recognized, as it provides the structural and biochemical properties that enable biofilm formation and virulence. The matrix also enables chemical or nutrient gradients to form, which can affect the behavior and survival of microorganisms. In periodontitis, inflammation and dysbiosis are reciprocally reinforced, and their interplay develops to become the driver of periodontitis in susceptible individuals. The subversion of the host response by periodontitis-associated bacteria, such as P. gingivalis, is a key factor in the development of periodontitis. These bacteria manipulate the host response to uncouple inflammation from bactericidal activity, which can enhance the adaptive fitness of the entire microbial community. New approaches to prevention and treatment of oral diseases are being explored, including the use of nanotechnology for drug delivery and the development of novel antimicrobial peptides. These strategies aim to target the biofilm matrix, the acidic pH microenvironment, and the polymicrobial synergies associated with acidogenesis. The integration of omics technologies and improved database curation andThe oral microbiota is a dynamic, polymicrobial community that plays a critical role in health and disease. It consists of diverse microorganisms that inhabit distinct microenvironments in the oral cavity, such as the surfaces of teeth and mucosal membranes. These communities are regulated by host and environmental factors and are essential for maintaining homeostasis or causing dysbiosis, which can lead to diseases like dental caries and periodontitis. These diseases are driven by a feedforward loop between the microbiota and host factors, such as inflammation and dietary sugars, which favor the emergence and persistence of dysbiosis. The oral microbiota is composed of a variety of bacteria, including streptococci and actinomyces, which are primary colonizers of oral surfaces. As the subgingival area becomes more anaerobic, the microbial composition shifts to include more strict anaerobes. The spatial and structural organization of microbial communities is also essential for physical and metabolic interactions that can be antagonistic or cooperative. In dental caries, overexposure to dietary carbohydrates and host factors promotes the production of extracellular polymeric substances (EPS) and acidic metabolites, leading to the accumulation of acidogenic and acidic microorganisms. This can result in the formation of a pathogenic biofilm that can cause caries. In periodontal disease, polymicrobial communities induce a dysregulated and destructive host response through a mechanism called polymicrobial synergy and dysbiosis. The microbiota associated with periodontal disease is influenced by 'specialist' microorganisms that possess metabolic functions and an elevated virulence potential. The oral microbiota is also associated with systemic diseases such as oral cancers and rheumatoid arthritis. The concept of polymicrobial synergy is central to understanding the pathogenesis of oral diseases, as microorganisms often interact synergistically to enhance colonization, persistence, or pathogenicity. The role of the extracellular matrix in the biofilm lifestyle is increasingly recognized, as it provides the structural and biochemical properties that enable biofilm formation and virulence. The matrix also enables chemical or nutrient gradients to form, which can affect the behavior and survival of microorganisms. In periodontitis, inflammation and dysbiosis are reciprocally reinforced, and their interplay develops to become the driver of periodontitis in susceptible individuals. The subversion of the host response by periodontitis-associated bacteria, such as P. gingivalis, is a key factor in the development of periodontitis. These bacteria manipulate the host response to uncouple inflammation from bactericidal activity, which can enhance the adaptive fitness of the entire microbial community. New approaches to prevention and treatment of oral diseases are being explored, including the use of nanotechnology for drug delivery and the development of novel antimicrobial peptides. These strategies aim to target the biofilm matrix, the acidic pH microenvironment, and the polymicrobial synergies associated with acidogenesis. The integration of omics technologies and improved database curation and