It is now becoming widely recognized that certain systemic diseases may increase the risk for periodontal disease. The hypothesis that oral conditions, such as periodontal infections, may be a risk factors or indicators for important medical outcome represents a paradigm shift in thinking about causality and the two-way directionality of oral and systemic associations. The current evidence also supports that prevention and treatment of periodontal disease may reduce chronic systemic disease risk at both the individual level and community level and the possibility that morbidity and mortality from systemic diseases may be reduced by improving periodontal health. Therefore, proper use of the knowledge of potential relationships between periodontal disease and systemic health requires the dental professionals to expand their horizons, to step back from the technically demanding aspects.