Ancient dentists drilled teeth 9,000 years ago, scientists say

Ancient man used sophisticated drills to treat tooth decay, according to a French anthropologist who turned up evidence of fine dental work in ancient Pakistani cemeteries.

Writing in the respected British journal Nature, Roberto Macchiarelli of the University of Poitiers said Neolithic man used drills made of tiny pieces of flint up to 9,000 years ago.

That means dentistry is at least 4,000 years older than first thought and far older than modern anesthesia.

Macchiarelli came to his conclusion after finding nearly perfect holes that had been drilled into the back teeth of nine skulls in a Pakistani graveyard. He carbon-dated the skulls and found the patients lived between 5500 BC and 7000 BC.

What surprised Macchiarelli was the sophistication of the dental work. The ancient dentists managed to drill holes into the large molars at the back of their patients' mouths, a tricky job even with modern equipment.

Some holes were 3.5 millimetres deep.

"The holes were so perfect, so nice," said David Frayer, an anthropology professor at the University of Kansas who co-authored the study. "I showed the pictures to my dentist and he thought they were amazing holes."

He believes the ancient dentists learned their trade drilling ornamental beads, a technique that was in vogue at the time.

Researchers found drill bits that were fashioned out of tiny pieces of flint and used tiny bows to spin them. Macchiarelli tried the technique with a home-made bow and drilled through a human tooth in less than a minute.

"Definitely it had to be painful," Macchiarelli said.

Researchers were impressed by how advanced the society was at such an early period. One patient had a tooth that was drilled twice. Another patient had three teeth drilled, while other teeth showed signs of cavities around the drill holes.

Macchiarelli found no sign of fillings, but he told Nature that a soft, asphalt material could have been used.