The Underlying Mechanisms of Pre- and Probiotics and Their Potential Role in Oral Health

Abstract Body: At health, microorganisms and their human host live in symbiosis: the microbes get the right nutrients and environment for their growth, in turn providing the host with the benefits for his or her health. This host-microbe relationship evolves in the first years of life, and, once established, remains stable. The specific properties of the host such as salivary pH and composition and the behavior of the host such as smoking, hygiene habits or intake of fermentable carbohydrates will shape the oral microbial community and its activity, resulting in a highly individual oral microbiome. In some cases, the interplay of these factors may lead to dysbiosis – a disturbed relationship between the host and its microbes - and even disease. If the host-microbe relationship is so stable, is it then possible to return to the balanced situation once it has entered the state of dysbiosis? In this presentation, two approaches gaining popularity in microbiome modulation – adding beneficial microbes (probiotics) to the oral ecosystem or promoting their growth with specific substrates (prebiotics) will be discussed. The current hypotheses on the potential underlying mechanisms of these two approaches will be critically assessed. Additionally, directions for further research will be highlighted.