Common amino acid can prevent dental plaque

A common amino acid found naturally in foods such as red meat, poultry, fish and dairy products, breaks down dental plaque, which could help millions of people avoid cavities and gum disease, scientists say.
Researchers from the University of Michigan and Newcastle University discovered that in the lab L-arginine, which is already used in dental products for tooth sensitivity, stopped the formation of dental plaque.
"This is important as bacteria like to aggregate on surfaces to form biofilms. Dental plaque is a biofilm," Alexander Rickard, assistant professor of epidemiology at the U-M School of Public Health, said.
Dental biofilms are the culprits in the formation of dental caries (cavities), gingivitis and periodontal disease.

Most methods for dental plaque control involve use of antimicrobial agents, such as chlorhexidine, which are chemicals aimed at killing plaque bacteria, but they can affect sense of taste and stain teeth.
The researchers said L-arginine could take the place of the current plaque-controlling biocide substances including chlorhexidine and other antimicrobials.

"At present, around 10-to-15 per cent of adults in the Western world have advanced periodontitis, which can lead to loose teeth and even the loss of teeth. Therefore, there is a clear need for better methods to control dental plaque," said Nick Jakubovics, a lecturer at Newcastle's School of Dental Sciences.

The mechanism for how L-arginine causes the disintegration of the biofilms needs further study, the researchers said.
It appears arginine can change how cells stick together, and can trigger bacteria within biofilms to alter how they behave so that they no longer stick to surfaces, they said.
The team members used a model system they introduced in 2013 that mimics the oral cavity. The researchers were able to grow together the numerous bacterial species found in dental plaque in the laboratory, using natural human saliva.
The finding was published in the journal PLOS ONE.