A Bronze Age mandibular anomaly from Gansu, China

Abstract

Bone defect in the mandible due to developmental defects, trauma, or diseases is common. However, large scale of mandibular bone atrophy induced by long‐term pressure is rare. This study reported a mandibular anomaly, possibly a secondary lesion, from a Bronze Age adult male excavated from the Dunping cemetery during the Eastern Zhou Dynasty (770–256 BCE), Zhang County, Gansu Province, China. The defect presents as an absence of bone mass at the angle of inferior lingual aspect of the mandibular corpus, incorporating the gonial angle of the mandible on the left side. Overall profile of the defect was assessed using morphological observations of the mandible, accompanied by computed tomography (CT) imaging and panoramic dental X‐ray images of the jaws used to assist with the diagnosis. There were no signs of trauma, osteogenic neoplasms, or osteolytic lesions. Pressure resorption, a Stafne defect, was postulated as the primary cause of bone atrophy due to a long‐term lesion of the neighboring submandibular gland, namely, chronic sialadenitis or a benign neoplasm pleomorphic adenoma. This is for the first reported case of a mandible anomaly as such identified from ancient China. This reporting enriches the knowledge of long‐term effects of pressure resorption in the human mandible.