Data from: A peculiar tooth renewal in a Jurassic ray-finned fish (Lepisosteiformes: †Scheenstia sp.)

Tooth replacement in vertebrates is extremely diverse, and its study in
extinct taxa gives insights into the evolution of the different dental
renewal modes. Based on µ-CT scans of a left lower jaw of the extinct fish
†Scheenstia (Actinopterygii – Lepisosteiformes), we describe in detail a
peculiar tooth replacement mode that is, as far as we could trace back in
the literature, unique among vertebrates. The formation of the replacement
teeth comprises a 180° rotation of their acrodin cap that occurs
intraosseously within bony crypts, and their setting up appears to be
synchronous. We propose a model for the dental renewal process, and
identify complementary anatomical features visible in the tomography such
as the junction between the different tooth-bearing bones
(prearticular-coronoid and dentary), as well as cavities corresponding to
intraosseous crypts, nervous and/or vascular canals. The location of the
cavities and their subsequent identification (e.g. Meckel’s cavity,
mandibular sensory canal) help settling the function of pores visible on
the bone surface and understanding their relation to internal anatomical
features. Finally, this tooth replacement mode raises the question whether
it is specific to †Scheenstia or rather related to a particular dentition
type and thus potentially occurs in other lineages.