How beneficial is bacterial prophylaxis to periodontal health?

The term "probiotics" has become common among general practitioners. There has been an explosion in the interest regarding this topic, which is reflected in the number of scientific publications. The World Health Organization defined probiotics as: "Living microorganisms which when administered in adequate amount confirms a health benefit on the host". Probiotics have been studied extensively in the gastrointestinal tract for their health-promoting effects and have shown promising results. However, in recent times, probiotics have also been used in periodontal health and have shown promising results in controlling gastrointestinal tract infections. Probiotics have potential, but as with many other clinical situations, multicenter or randomized, controlled studies on humans are still required before they can be recommended as prophylaxis for caries or periodontal disease. In the present study, we review the effects of probiotics on maintaining periodontal health. Relevant studies were identified from 1970 to February 2010 using Old Medline, Cochrane Library, and Google Scholar.