1. World Health Organization, Health Topics Oral Health http://www.who.int/topics/oral_health/en/
2. Systemic diseases caused by oral infection;Li;Clin Microbiol Rev,2000
3. Periodontal disease and diabetes mellitus: a two-way relationship;Grossi;Ann Periodontol,1998
4. World Health Organization, Media Center Oral Health http://www.who.int/mediacentre/factsheets/fs318/en/
5. The global increase in dental caries. A pending public health crisis;Bagramian;Am J Dent,2009