Abstract: This paper presents a study of the tooth wear, oral diseases and masticatory pressure on the human teeth from Jiayi Cemetery (10th~2nd Century BC), which is located in Turpan City, Xinjiang Province. Results indicate that Jiayi ancient population had a heavy tooth wear, while both their anterior and posterior teeth were suggested to be used actively during their whole lives. Besides, their teeth show a remarkable and high-frequent oblique wear pattern, which is especially obvious on their molars. We also found that very few individuals (1.6% of teeth, n=1115; 18.8% of individuals, n=69) suffered from dental caries. Other oral features and diseases, including antemortem tooth loss (43.5%), Calculus (71.0%), abscessing (46.4%) and periodontal disease (37.7%) were also found to be common among this ancient population (percentages by individuals, n=69). 9 individuals (13.0%) showed obvious mandible exostoses, which means they had been under heavy masticatory pressure for a long time before death. The low rate of caries indicates that grain foods were not that common in Jiayi people’s diet, while oblique wear pattern is an obvious sign on the teeth of people whose daily staples are always made of grains. In order to analyze the oblique wear pattern of Jiayi ancient population, we carried a quantization study which is built on the use of Wear Orientation (Iwo) on their molars. Ethnological investigations, archaeological findings and modern medicine researches were also considered in our discussion of the factors account for the complicated wear pattern and oral diseases. Clues show that Jiayi ancient population might rely much on hard foods, especially some kinds of processed grain foods, to adapt to the tough environment and their nomadic lifestyle. This hypothesis is likely to be the answer to the confusing features of Jiayi people’s teeth. According to our conclusion, meat occupied a main part of Jiayi ancient population’s diet, while grain foods were also among the important compositions. The tough environment in Turpan Depression, as well as the unique food procession technologies to make food adaptable for their nomadic lifestyle may have caused the hardness of daily foods for Jiayi ancient population, thus led to the oblique wear pattern and heavy wear on their posterior teeth.

Key words: Turpan; Jiayi Cemetery; Bronze-Iron Age; Tooth wear