The medial mandibular bone concavity (Stafne's defect).
D001845:Bone Cysts / Q000000981:diagnostic imaging*; D001848:Bone Diseases, Developmental / Q000000981:diagnostic imaging*; D003937:Diagnosis, Differential; D006801:Humans; D008336:Mandibular Diseases / Q000000981:diagnostic imaging*; D010026:Osteosclerosis / Q000000981:diagnostic imaging; D011859:Radiography