Periodontal Disease and Bad Breath
The link between periodontal disease and bad breath has been recognized for many years - though not all people with bad breath have gum disease, many people with gum disease suffer from bad breath. The connection between the two is bacteria. A whole group of bacteria that live in the mouth are known to break down proteins in their environment and produce volatile sulfur compounds (VSC) that have a very unpleasant smell. The bacteria involved are predominantly anaerobic - they live in environments where there is little or no oxygen - and they are found in gum pockets, in the grooves and crevices on the back of the tongue, and around the tonsillar crypts.
Scientific studies have explored the relationship between the periodontal bacteria that are thought to cause much of the tissue destruction in gum disease, and the presence of breath odor in patients suffering from gum disease. A study by S. Awano and others, "The Relationship between the Presence of Periodontopathogenic Bacteria in Saliva and Halitosis," (International Dental Journal: 2002 Jun;Suppl 3:212-6) looked for four species of bacteria in patients with both periodontal disease and bad breath. Researchers also measured levels of volatile sulfur compounds - hydrogen sulfide and methyl mercaptan. The results indicated that Bacteroides forsythus, Porphyromonas gingivalis, and Prevotella intermedia were all associated with VSC production, with B. forsythus being the most significant producer of all.
Other studies investigating the habitats of periodontal bacteria have shown that B. forsythus lives on the lining of the mouth in locations other than infected gum pockets in healthy people as well as those with gum disease, and P. intermedia is frequently found living on the surface of the tongue. Thus, while there is a clear association between periodontal disease and bad breath, there is also good evidence to support the claim that periodontal bacteria can be the source of bad breath, even in the absence of gum disease.
Scientific study of both periodontal disease and bad breath continue to reveal information that is helpful to those who suffer from these conditions. These studies suggest that remedies for bad breath that target periodontal bacteria are likely to bring positive results, and that achieving a permanent change in the bacterial microflora of the mouth might cure bad breath.