Differential bioarchaeological assessment of an intraoral stone object from a Warring States-period Qin burial, China

Objects associated with oral cavities in archaeological contexts may reflect antemortem dental intervention, deliberate postmortem treatment, or taphonomic movement. This study examines a cylindrical object reported within a pathological alveolar cavity in the right maxillary second molar region of the individual from Burial M280, a Warring States-period Qin grave at Beishenjiaqiao cemetery in Xi’an. Compositional and density data were consistent with a carbonate-rock composition. Macroscopic, radiographic, microscopic, and contextual analyses revealed no fixation features, masticatory wear, artificial preparation, or adaptive osseous response. Together with severe alveolar abscess formation and loss of the buccal root, these observations strongly argue against sustained antemortem use as a prosthesis or implant. Deliberate postmortem placement remains plausible, but non-intentional postmortem entry or later displacement cannot be excluded because the original object–sediment–bone relationship was not documented before removal. The case illustrates a structured differential approach to evaluating comparable object–oral associations in archaeological contexts.