Researchers found a “microbial Pompeii” on the teeth of 1,000-year-old human skeletons.
Just as volcanic ash entombed the citizens of the ancient Roman city, dental plaque preserved bacteria and food particles on the skeletons’ teeth, reports LiveScience.
They analysed dental plaque from skeletons in a medieval cemetery in Germany, and found that the mouths of these aged humans were home to many of the same bacterial invaders that cause gum disease in the mouths of modern humans.
“One thing that is clear about the population we studied is that they didn't brush their teeth very often, if at all,” said study leader Christina Warinner, an anthropologist at the University of Zurich in Switzerland and the University of Oklahoma in Norman.
The discovery of these bacteria also revealed clues to the dental hygiene and diets of these centuries-old humans, according to the study detailed today (February 24) in the journal Nature Genetics. [5 Surprising Ways to Banish Bad Breath]
Plaque is a dentist's worst enemy, but it turns out to be a great time capsule for preserving the bacteria (or "microbiome") and bits of food on the teeth of humans long after they die. The sticky bacteria on teeth trapped particles of food and other debris, and over time, the calcium phosphate in saliva — the same mineral found in bones and teeth — caused the plaque to calcify into tartar.
“We knew that calculus preserved microscopic particles of food and other debris but the level of preservation of biomolecules is remarkable — a microbiome entombed and preserved in a mineral matrix, a microbial Pompeii,” another study researcher, Matthew Collins from the University of York, in England, said in a statement.