Saturday 26 April 2014

A palliative dental filling from the Neolithic of Slovenia.

Dentistry is known to have been practiced by the Ancient Egyptians, and several examples of putative Neolithic dental interventions have been recorded from between 7500  and 9000 years ago in Pakistan, around 7000 years ago in northern Italy and pre-historic Egypt, where a 5500-year-old artificial tooth was reported in 2004.

In a paper published in the journal PLoS One on 19 September 2012, a team of scientists led by Federico Bernardini of the Multidisciplinary Laboratory at the Abdus Salam International Centre for Theoretical Physics in Trieste, describe the occurrence of a beeswax filling in the canine tooth of a 6500-year-old human mandible (jawbone) from a karst cave near the village of Lonche, in northern Istria, southern Slovenia. 

The mandible was discovered in the 1930s alongside late Pleistocene animal remains, but given only a brief description at the time, and has remained in the Natural History Museum of Trieste in the intervening time.  Recent examination of the bone, including radiocarbon dating has revealed it to be considerably younger than originally thought, dating from around 6655-6400 years ago. At this time the area was occupied by the Vlaška Culture, who had an economy based on Sheep-breeding and who built stone shelters for themselves and their animals. The specimen is thought to have come from an adult male, and is a portion of the left mandible with a canine, two premolars, and the first two molars in position.

The Lonche jaw from a karstic cave of southern Slovenia. Scale bar is 10 mm. Bernardini et al. (2012).

All of the teeth show significant wear, with the canine being particularly bad. This has a deep vertical fracture reaching the dentine layer, combined with a number of smaller horizontal fractures within the tooth, and is likely to have been extremely painful in life, particularly when the tooth was in use.

Volume rendering of the canine crown showing the fractures through the dental tissues in transparency. The main vertical fracture (in blue) and the sub-horizontal ones (in red) are shown in lingual (A), distal (B) and occlusal view (C). Scale bar is 1 mm. Bernardini et al. (2012).

Traces of an unknown substance were found within the cracks on the tooth, and subjected to spectrographic analysis, which suggested the substance was almost certainly beeswax, which is known to have been used as a binding agent in Ancient Egyptian dentistry. Radiocarbon dating of this beeswax confirmed that it was of similar age to the tooth, not a later inclusion.

SEM images of the occlusal surface of the Lonche canine after the beeswax was removed. The Figures (A) and (B), respectively taken before and after cleaning the occlusal surfaces from beeswax superficial residues, show the exposed area of dentine resulting from occlusal wear and the vertical crack still filled with beeswax. Some chippings with round and smooth edges, indicated by the white arrows in Figure (A) are present on the occlusal buccal margin of tooth. In Figure (A1) residues of beeswax cover the edges of the vertical crack, while Figure (B2) shows that some enamel fragments are lost in the same area, indicated by yellow arrows. Scale bars are 200 mm. Bernardini et al. (2012).

The beeswax is found only on the one tooth, and appears to have been applied after the crack formed. It is possible that the wax was applied post-mortem, but it is not clear why it would be applied only to the one tooth, and no such covering has been found on the teeth of any other Vlaška Culture burial, making it more likely that the beeswax was applied in life, and in response to the injury to the tooth. A beeswax filling would be unlikely on its own to provide much mechanical support for a damaged tooth, but it would have served to cover the exposed dentine, and to prevent food from entering the cavity, thereby reducing the pain of the injury. Bernardini et al. therefore conclude that the filling is likely to have been palliative in nature.

See also…
Follow Sciency Thoughts on Facebook.