By Tim Hyland
But exactly how this particular bug has been so dangerous has in some ways always been a mystery. As researchers have known for some time, P. gingivalis--despite its nasty nature--has one key vulnerability: in a healthy mouth, it’s generally rare, and is incapable of producing the growth molecules necessary for it to multiply.
BACTERIAL RELATIONSHIP COMPOUNDS GUM DISEASE
So why has P. gingivalis been able to persist as such a pesky opponent of oral health? According to researchers led by a team from the University of Buffalo, the answer lies in its relationship with yet another bacteria--one that, on its own, poses little threat.
The bacteria in question Veillonella parvula. Researchers consider it to be largely non-pathogenic, though studies have shown that, in rare cases, it can be linked to conditions such as meningitis or periodontal disease. In the oral microbiome, however, its principal threat appears to be the service it provides to P. gingivalis.
As the Buffalo research team found, since P. gingivalis can’t easily multiply on its own, it actually uses V. parvula to do so. For their study, the results of which were published in the ISME Journal, the researchers examined the relationship between P. gingivalis and several other bacteria, hoping to crack the code of its unexplained ability to grow in absence of its own multiplying mechanism.
What this team of researchers ultimately found was hardly shocking: the underlying issue in most cases of problematic growth of P. gingivalis was poor dental hygiene, which resulted in the build-up of plaque. That build-up led to the presence of more and more V. parvula. And this, they say, is where P. gingivalis takes hold.
Once V. parvula is present in the biome, the researchers found, P. gingivalis is then able to “borrow” growth molecules from its companion bacteria, and to multiply.
Notably, the researchers said, with no other pathogen in the biome, there is no beneficial relationship for P. gingivalis outside of the role it plays with V. parvula. This is an important finding, they say, because it opens up new pathways for preventative treatments that can specifically target V. parvula, and thus reduce the harmful impacts of P. gingivalis.
“Having worked with P. gingivalis for nearly two decades, we knew it needed a large population size to grow, but the specific processes that drive this phenomenon were not completely understood,” said Patricia Diaz, DDS, Ph.D., lead investigator on the study and Professor of Empire Innovation in the University of Buffalo School of Dental Medicine, in a press release issued by UB. Dr. Diaz goes on to state, “Successfully targeting the accessory pathogen V. parvula should prevent P. gingivalis from expanding within the oral microbial community to pathogenic levels.”
According to the Center for Disease Control and Prevention, more than 47 percent of adults age 30 and older suffer from some form of periodontitis. As we see by this research, a greater understanding of the relationship between the bacteria P. gingivalis and V. parvula will increase targeted therapies for periodontitis in patients.
About the Author: Contributing writer Timothy Hyland has more than 20 years' experience as a writer, reporter, and editor. His work has also appeared in Fast Company, Roll Call, Philadelphia Business Journal, and The Washington Times.