Can periodontitis or other inflammatory processes of the oral cavity contribute to systemic conditions such as atherosclerosis or diabetes? Can they negatively influence their course? This new installment in the Cell-to-Cell Communication series addresses these issues by focusing on the associations linking periodontal and systemic health. The film visualizes the highly complex intercellular interactions and signaling pathways. Periodontal pathogens are invasive and can spread throughout the body via the bloodstream. Locally produced pro-inflammatory mediators can also shed into the circulation. This new film shows the dissemination of bacteria in periodontitis, the impact of periodontitis on the cardiovascular system (atherosclerosis), the effect of periodontitis on the metabolism (type 2 diabetes), and the effect of dental treatment.