Dental disease in the Chinese Yin-Shang period with respect to relationships between citizens and slaves.
Seventy-one skulls from the Yin-Shang period tombs of Anyang, China, were examined for the incidence of observable dental diseases, including dental caries, alveolar bone resorption (an index of periodontal disease), ante-mortem tooth loss and tooth attrition. Because the remains were excavated from tombs with funerary items, the burials are believed to be of Anyang citizens. Our study indicates carious tooth frequency in the Yin-Shang period was rather low (2.9-4.0%). Periodontal disease frequency was 18.3-26.9%, and ante-mortem tooth loss frequency was 2.0-7.5%. To determine the relative prevalence of overall dental health in the Yin-Shang populations, observations from the 42 male crania were compared to those from 183 male crania of slaves from "sacrificial pits" from the Yin-Shang period (Inoue et al. [1992] J. Anthropol. Soc. Nippon 100:1-29). Results from this comparison indicate no apparent difference between social classes in younger age groups. However, in the older ages the rates of the ante-mortem tooth loss, periodontal disease and tooth attrition were significantly higher in the citizen sample. The findings would suggest dietary development in the Yin-Shang period was not dissimilar enough between social classes to induce clear differences in dental diseases at least at younger ages. Conversely, it appears there must have been significant differences between social classes diets in the earlier phase of the Yin-Shang period to produce the differences in dental disease present in the older samples.