Saving billions of teeth from a blood-eating mouth bug, Pg

You’ll want to brush your teeth after reading this media release

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Melbourne is hosting a global conference this week of experts in the fight against a blood-eating bug that’s destroying bone and causing tooth loss in nearly one billion people, including nearly three million Australians.

“Most of us will get a bit of mild gum disease or gingivitis from time to time when ‘bad’ bacteria in our mouths get out of balance with ‘good’ bacteria,” says Professor Eric Reynolds, the Conference Chair. “Bacteria get between our gums and our teeth and an inflammation kicks off. If we’re unlucky then Pg moves in.”

“As this blood-eating bacterium grows in a biofilm (plaque) next to the gums it creates an environment that protects it and other similar bacteria in the plaque. It also changes the ecology of the mouth, setting off a cycle of inflammation and disease leading to the loss of bone from your jaw. Then your teeth fall out,” says Reynolds who is also Director of the Oral Health CRC based at The University of Melbourne. Quarterly scraping of the plaque helps, but doesn’t eliminate the infection in some individuals.

But that’s the good news. Over the past decade around the world evidence is mounting that Pg (Porphyromonas gingivalis) is doing harm throughout the body.

At the conference:

  • US and Polish researchers will report that antibodies to Pg are found in people with rheumatoid arthritis
  • Japanese researchers will report that Pg could be acting by changing the mix of bacteria in the gut
  • Melbourne researchers will report on a potential drug target that could lead to treatments for arthritis and gum disease
  • Adelaide researchers will discuss how Pg affects pregnancies in mice, helping to explain wide-spread epidemiological evidence that mums with gum disease are more likely to have babies with low birth weight.

Solutions are on the way:

  • Milk-based probiotics help reduce bone loss in mice in Adelaide
  • A US team will report on their peptide to fight Pg
  • A Chinese team will report on using nano-capsules of the traditional Chinese herb, Chinese Skullcap
  • Using the right oral health products in the right way we can fight Pg and encourage the right bugs to grow, says UK researcher Philip Marsh.

And a vaccine is on its way. Eric Reynolds will report on a vaccine developed by The University of Melbourne and the Oral Co-operative Research Centre that aims to break the cycle of infection in people with severe gum disease.

For now, “You can stop Pg from establishing in plaque below the gum line: brush, floss, and see your dentist regularly.”

For interviews contact Professor Eric Reynolds via

PgMelbourne2017 is the 3rd International Conference on Porphyromonas gingivalis and Related Species in Oral and Systemic Diseases is supported by the Oral Health CRC, the CRC Program, The University of Melbourne, CSL and the Melbourne Convention Bureau.