Abstract:

Dental attrition patterns, affected by dental health, occlusal morphology, masticatory mechanics, and dietary habits, offer crucial insights into ancient subsistence strategies. To systematically explore these relationships, this study combines macroscopic wear grading, three - dimensional occlusal analysis, and microwear striation quantification to reconstruct the dietary patterns of the Eastern Zhou people (770-221 BC) from Dunping Cemetery in Gansu Province. Methodologically, 775 dental specimens from 69 individuals were analyzed, covering wear grades, 3D wear indices, and microwear metrics.
First, based on Smith’s (1984) classification for dental wear, the values of tooth wear grades and the wear index ratios between anterior and posterior teeth were calculated. The results show that the Dunping people had greater wear in anterior teeth than in posterior teeth in both the maxillary and mandibular dentitions, and this difference was more significant in the mandible. Compared with other ancient Chinese groups from the Neolithic to the early Iron Age, the Dunping people presents a distinct pattern. Generally, it has lower anterior tooth wear relative to posterior tooth wear, a trend that differs from the main characteristics seen in contemporaneous comparative peoples.
Subsequently, an integrated approach involving high-precision dental model fabrication, three-dimensional laser scanning, and computer-aided analysis software was employed to systematically analyze and collect crown surface area and outline projection area data for 3D occlusal topography reconstruction. Three-dimensional wear index (IWS) and occlusal surface index (IOS) were calculated to quantify crown wear severity for comparative analysis. The results revealed that the Dunping people had lower IWS and IOS values. This indicates a distinct wear pattern with limited dentine exposure, reduced cuspal attrition, and preserved occlusal topography that had not yet reached the planarization stage, which is consistent with light occlusal wear. These findings are in line with previous dental wear grade assessments showing lower molar attrition levels in this people.
In addition, dental microwear analysis was carried out using extended depth - of - field electron microscopy, with intergroup comparisons based on striation length ratios at different angles on the buccal surfaces. Principal component analysis showed that the L_h/L_v index (104.73%) of the Dunping group was closer to that of the pastoralist Jiayi group. This suggests that, compared with agricultural peoples, the Dunping group had relatively lower proportions of plant - derived components in their dietary composition. This quantitative pattern implies potential subsistence strategies with mixed dietary sources and significant consumption of animal products.
In conclusion, the integrated research findings show that the Dunping people has distinct dental wear characteristics: relatively low molar attrition levels, greater anterior tooth wear than posterior teeth, obvious anterior dental abrasion, shallow occlusal grooves in molars, and a predominance of vertically oriented buccal microwear striations. This pattern suggests a protein-rich dietary profile mainly composed of animal products. Archaeological evidence from Eastern Zhou period burials at the Dunping cemetery supports this interpretation. The mortuary assemblage shows little evidence of agricultural features but reveals extensive use of animal remains, such as cattle, horses, and sheep, as sacrificial offerings. These findings support the conclusion that the subsistence economy was mainly based on pastoralism with minimal agricultural integration. The dietary structure likely emphasized animal - derived nutrition, which is consistent with the observed dental wear signatures indicating less mastication of fibrous plant materials and more processing of softer, meat-based foods.

Key words: Dunping cemetery, Eastern Zhou Dynasty, dental wear, dietary