Figure 5

Periodontal ligament attachment in the rabbit (Oryctolagus cuniculus; UALVP 56918) and hadrosaurid (UALVP 56336). (a) magnified image view of the box in (c) of rabbit alveolar bone and the root portion of the incisor; (b) corresponding view in the hadrosaurid dental battery between alveolar bone and the tooth root; (c) sagittal view of rabbit histological thin section; (d) hadrosaurid dental battery (UALVP 11734) showing location of lingual plate [note: the lingual plate in this specimen is incomplete and would reach closer to the occlusal surface in life]; (e) magnified image of the box in (c) of rabbit alveolar bone and the crown portion of the incisor; (f) corresponding view in the hadrosaurid dental battery between the lingual plate and the tooth crown (ROM 3500). (a), (c), and (e) are in sagittal view, while (b) is in transverse view, (d) is in medial view, and (f) is in coronal view. ab, alveolar bone; c, cementum; de, dentine; en, enamel; lp, lingual plate; pcts, periodontal connective tissue space; pds, periodontal space; os, occlusal surface; sf, Sharpey’s fibers.