Cigarettes build 'fortified city' for germs inside mouth

Housing millions of germs, mouth is certainly the 'dirtiest' parts of the body. However puffing cigarettes makes it even filthier and may make even more convenient for certain bacteria like Porphyromonas gingivalis to camp in there.

University of Louisville School of Dentistry researcher David A. Scott, Ph.D., explores how cigarettes lead to colonization of bacteria in the body. Scott and his research team have identified how tobacco smoke, composed of thousands of chemical components, is an environmental stressor and promotes bacteria colonization and immune invasion.

Scott says since this initial finding several years ago, a recent literature review published in Tobacco Induced Diseases revealed that cigarette smoke and its components also promote biofilm formation by several other pathogens including Staphylococcus aureus, Streptococcus mutans, Klebsiella pneumonia and Pseudomonas aeruginosa.

Biofilms are composed of numerous microbial communities often made up of complex, interacting and co-existing multispecies structures. Bacteria can form biofilms on most surfaces including teeth, heart valves and the respiratory tract.

One of the most prevalent biofilms is dental plaque, which can lead to gingivitis - a gum disease found in almost half the world's population - and to more severe oral diseases, such as chronic periodontitis. Bacterial biofilms also can form on heart valves resulting in heart-related infections, and they also can cause a host of other problems.

"We are continuing research to understand the interactions of the elaborate communities within biofilms and how they relate to disease. Many studies have investigated biofilms using single species, but more relevant multispecies models are emerging. Novel treatments for biofilm-induced diseases also are being investigated, but we have a long way to go," Scott said.

Attention to Scott's work comes as the World Health Organization observes World No Tobacco Day on May 31 to encourage a global 24-hour abstinence from all forms of tobacco consumption. The effort points to the annual 6 million worldwide deaths linked to the negative health effects of tobacco use.

In the United States, Kentucky ranks second for cigarette use among adults, according the Centers for Disease Control and Prevention (CDC). Only West Virginia has more smokers. Kentucky also brings up the rear among youth in grades 9-12 who use tobacco; according to 2011 CDC data, about 24-percent of high school students smoke cigarettes.

This research has been published in Tobacco Induced Diseases.