Mechanical and chemical dental wear in historical population from the Syrian lower Euphrates valley.

OBJECTIVES: The aim of this study was a comprehensive macro- and microanalysis of dental wear observed in the populations inhabiting the Syrian lower Euphrates valley. We may assume that social changes have had an important impact on the dietetic and hygienic habits of the local population. MATERIALS AND METHODS: Six periods were chosen: Early Bronze (2650-2350 BC), Middle Bronze (2200-1700 BC), Neo-Assyrian (900-700 BC), late Roman (AD 200-400), Islamic (AD 600-1200), and modern Islamic (AD 1850-1950). The dental remains belong to 196 individuals, with a total of 3292 teeth. Mechanical dental wear was evaluated according to Smith's and Shykoluk & Lovell's scale. Also, SEM technique was used to select teeth. RESULTS: Individuals from both Bronze Ages were characterized by a large percentage of severe dental wear, contrary to the younger chronological periods. The rate of dental wear slowed down from the Middle Bronze Age. The frequency of deep scratches, punctures, and pits successively decreased with younger periods, while striae became more frequent. The highest number of teeth diagnosed with erosive loss was from the Neo-Assyrian period. DISCUSSION: In the Early and Middle Bronze Ages the diet was rather hard and more contaminated. The diet in the Neo-Assyrian period was rich in products lowering the pH in the oral cavity. The frequency of dental erosion in two consecutive periods--Islamic and late Roman--took place at a similar level. Thus similar alimentary habits in these periods can be suggested.