www.nytimes.com

PARIS, FRANCE, April 5, 2006: Man’s first-known trip to the dentist occurred as early as 9,000 years ago, when at least 9 people living in a Neolithic village in ancient India had holes drilled into their molars and survived the procedure. The findings, to be reported Thursday in the scientific review Nature, push back the dawn of dentistry by 4,000 years to around 7000 B.C. The drilled molars come from a sample of 300 individuals buried in graves at the Mehrgarh site in what is now western Pakistan, believed to be the oldest Stone Age complex in the Indus River valley. “This is certainly the first case of drilling a person’s teeth,” said David Frayer, professor of anthropology at the University of Kansas and the lead author of the report. “But even more significant, this practice lasted some 1,500 years and was a tradition at this site. It wasn’t just a sporadic event.” The earliest previously known evidence of dental work done in vivo was a drilled molar found in a Neolithic graveyard in Denmark dating from about 3000 B.C. All 9 of the Mehrgarh dental patients were adults — 4 females, 2 males, and 3 individuals of unknown gender — and ranged in age from about 20 to over 40. Most of the drilling was done on the chewing surfaces of their molars, in both the upper and lower jaws, probably using a flint point attached to a bow that made a high-speed drill, the researchers say. Concentric ridges carved by the drilling device were found inside the holes.

Dental health was poor at Mehrgarh, though the problems were less often tooth decay than brutal wear and tear. Roberto Macchiarelli, professor of paleoanthropology at the University of Poitiers, France, and the report’s lead anthropological researcher, attributed the bad teeth to the Neolithic diet, which included newly domesticated wheat and barley. “A lot of abrasive mineral material was introduced when grains were ground on a stone,” Professor Macchiarelli said, “and as these people moved to a grain diet, their teeth wore down, dentin was exposed, and the risk of infection rose.” None of the individuals with drilled teeth appears to have come from a special tomb or sanctuary, indicating that the oral health care they received was available to anyone in the society.

The dentists may have been highly skilled artisans at Mehrgarh, where beads of imported lapis lazuli, turquoise, and carnelian were found drilled with holes even smaller than the ones in the nine individuals. Discovered among the beads were finely tipped drill heads. “The drilling of teeth is very rare in the anthropological record,” said Professor Macchiarelli, noting that work similar to that done at Mehrgarh does not recur until much later, among the Anasazi Indians of the southwest United States around 1100 A.D., and in Europe around 1500 A.D. The 1,500-year-long tradition of drill work at Mehrgarh appears not to have been passed down to later cultures. There is no evidence that the Chalcolithic, or Copper Age, people who next lived there ever visited the dentist. Why the practice came to a halt is not known.