BACKGROUND: Tooth loss not only impairs oral function but also affects gut health by altering the host microbiota. Understanding the oral-gut axis can provide insights into systemic health implications following tooth loss. METHODS: Using an animal model, we extracted the molars of C57 mice. Saliva and fecal samples were collected for 16S rRNA and metagenomic sequencing to analyze changes in the oral and gut microbiota. Pearson correlation analysis assessed the relationship between altered microbial communities. RESULTS: The study found a significant reduction in oral microbiota diversity following tooth loss, with increased Proteobacteria and decreased Muribacter. Gut microbiota showed increased Firmicutes and decreased Bacteroidota. Correlations between oral and gut microbiota changes were observed, indicating a potential link between tooth loss and alterations in intestinal microbial balance. CONCLUSION: In the mouse model, tooth loss disrupted the balance of the oral-gut microbiota, with potential implications for intestinal health. Although these findings are from a murine model, considering the existence of the oral-gut axis balance in the human body, it is reasonable to postulate that following tooth loss in humans, the health of the intestinal microecology may also warrant attention.