There is growing awareness of oral/systemic links, especially with regard to periodontal disease, diabetes, and cardiovascular disease, among others. The process of dental caries has similar links. Bacterial and other acids in the oral environment can erode enamel and potentially initiate an inflammatory response in the dentin. The body's own matrix metalloproteinases, mostly from within the dentin, become activated, resulting in the caries process. A simplified explanation of the oxidative stress causing inflammation is developed from three equations, namely Health, Disease, and Disease. The healthy tooth is nourished by a centrifugal dentinal fluid flow. This flow is controlled by signals from the hypothalamus that are relayed to the endocrine portion of the parotid gland. The first step in the caries process is the reversal of the dentinal fluid flow, rather than the acid attack from the oral environment. A systemic understanding of the actual cause and progression of dental caries creates opportunities for more effective approaches to preventive care.