Temporal pattern of dental caries at the western flank of the Central Plateau of Iran, c. 2700 BCE – 1600 CE

Abstract

Objective

To analyze the overall frequency and inter-tooth patterns of caries in three populations from ancient cemeteries located along the western border of the Central Iranian Plateau as a means to explore whether the populations of Iran had greater access to fermentable sugars after the establishment of the great empires.

Materials

Dental collections from Kafarved-Varzaneh (Early Bronze Age, MNI=66), Estark-Joshaqan (Iron Age, MNI=57), Tappeh Poustchi (Timurid and Safavid Period, MNI=34), together with comparative data from NE Syria.

Methods

Frequencies of dental caries per tooth categories, location and size of carious lesions are analyzed using Smith’s Mean Measure of Divergence, Correspondence Analysis, χ² and Kruskal-Wallis tests.

Results

There are minimal differences in overall frequencies of carious lesions at Iranian sites, regardless of the chronology, but notable differences at Syrian sites. The inter-tooth pattern at the Iron Age cemetery in Estark appears distinctly different than the other Iranian sites and the comparative samples from Syria.

Conclusions

Divergent subsistence strategies may be linked with different inter-tooth patterns since people buried at Estark were mobile herders, while the other cemeteries were used by settled farmers.

Significance

This comprehensive research on dental caries in three chronologically diverse populations in Iran sheds light on the association between dental caries and subsistence strategies, and introduces the Smith’s Mean Measure of Divergence to explore inter-tooth carious patterns, which may prove useful to other researchers seeking to understand the relationships between subsistence, diet, and the presence of carious lesions.

Limitations

The studied sample size is relatively small and therefore its temporal/regional distribution produces low-resolution results.

Suggestions for further research

More systematic research on the patterns of dental caries is necessary to produce more fine-grained reconstructions of diet and subsistence in Iran and around the globe.