Ancient cavity-creating bacteria found in Bronze Age teeth
- Published
- comments
Scientists in Ireland have found cavity-creating bacteria in two 4000-year-old molars (back teeth used for chewing).
Going to the dentist may feel like a chore, but it's an important part of keeping our teeth healthy.
Without brushing twice daily and regular check-ups, bacteria can create things called cavities, which is where the tooth gets eaten away by bacteria and little holes appear in them.
Thousands of years ago though, people didn't have dentists, or even toothpaste, so teeth rotting would be common.
What isn't common is for the bacteria that cause the rotting to stay alive until now!
The teeth were found in a cave in County Limerick in Ireland, and scientists at Trinity College Dublin said they contained an "unprecedented quantity" of the DNA of streptococcus mutans, a type of bacteria in the human mouth responsible for cavities.
The teeth are believed to be from the mouth of a man who lived in the Bronze Age.
This was a period in British and Irish history when settlers came from mainland Europe with new skills, such as making things out of copper.
Want to learn more about the Bronze Age? Check out this guide from BBC Bitesize
Scientists recreated the DNA, and say their work will help them understand what people's diets were like back then.
They said their analysis shows the the bacteria has changed a lot from the Bronze Age to today, and think that our love of sugar in modern times may have sped up its evolution.
They said it is "exceptionally rare" to find S. mutans in ancient tooth samples as this bacteria produces acids that not only cause tooth decay but also destroys DNA, meaning the bacteria is usually long dead by the time modern scientists dig the teeth up.
The researchers said the conditions of Killuragh Cave may have helped preserved the bacteria's DNA.
Lara Cassidy, an assistant professor at Trinity College Dublin, said: "We were very surprised to see such a large abundance of mutans in this 4,000-year-old tooth.
"It is a remarkably rare find and suggests this man was at high risk of developing cavities right before his death."