The find represents the oldest archaeological example of an operative manual intervention on a pathological condition, according to researchers led by Stefano Benazzi, a paleoanthropologist at the University of Bologna.
"It predates any undisputed evidence of dental and cranial surgery, currently represented by dental drillings and cranial trephinations dating back to the Mesolithic-Neolithic period, about 9,000-7,000 years ago," says Benazzi.
The patient was a young man, about 25 years old, living in northern Italy.
His well-preserved skeleton was found in 1988 in the Veneto Dolomitesnear Belluno, in a rock shelter burial named Ripari Villabruna.
The find was directly dated between 13,820 and 14,160 years old. It's now kept at the University of Ferrara for further studies.
"The treatment went unnoticed for all these years. The cavity was described as a simple carious lesion," says Benazzi.
Detailing their finding in the journal Scientific Reports, Benazzi and colleagues show that forms of dental treatment were already adopted in the Late Upper Palaeolithic.
At that time, toothpicks probably made of bone and wood were used to remove food particles between teeth.
However, until now, no evidence had been found to associate Palaeolithic toothpicking with tooth decay.
Beewax dental filling was discovered in a 6500 year old human tooth from Slovenia, while dental drilling, likely to remove decayed tissue, was discovered in 9000-year-old molars from a Neolithic graveyard in Pakistan.
Benazzi and colleagues analysed the lower right third molar of the Villabruna specimen. They noticed the tooth retains a large occlusal cavity with four cavities.
Using scanning electron microscopy the researchers uncovered peculiar striations in the internal surface of the large cavity.
"They were the result of a variety of gestures and movements associated with slicing a microlithic point in different directions," says Benazzi.
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Experimental tests carried out on the enamel of three molars using wood, bone and microlithic points confirmed the striations are characteristic of scratching and chipping.
"Basically, the infected tissue was picked away from inside the tooth carefully using a small, sharp stone tool," says Benazzi.
"This shows that Late Upper Paleolithic humans were aware about the deleterious effects of caries, and the need to intervene with an invasive treatment to clean a deep dental cavity," he adds.
The researchers noted the enamel was partially rounded and polished due to wear, indicating the treatment was carried out long before the death of the individual.
The find suggests that dentistry evolved from the much older practice of toothpicking, rather than from drilling procedures.
According to co-author Marco Peresani at the University of Ferrara, the discovery represents a key moment in the development of dental surgical practices.
"It shows that humans combined dexterity and creative skills and properly managed technology for producing tools also in early dental medicine well before the Neolithic, " says Peresani.
Source:http://www.abc.net.au/science/articles/2015/07/17/4275657.htm
