The detection of weakly developed plicidentine in teleost teeth using 3D tomography
The detection of weakly developed plicidentine in ground sections can be difficult, because these structures cannot always be resolved by analysing two-dimensional thin-sections. X-ray tomography followed by 3D virtual modelling allows the non-destructive study of the spatial morphology of these important structures. Here, we illustrate dentine folds in the pulp cavity of the teeth in three teleost fishes, Arapaima gigas (Osteoglossiformes), Hoplias aimara (Characiformes) and Lophius piscatorius (Lophiiformes), and add data from a lepisosteid, Lepisosteus platostomus, for comparison. Our observations confirm the presence of plicidentine previously described in these species using ground sections. We also describe for the first time the plicidentine organisation in teeth of the knifefish Chitala chitala (Notopteridae), the African electric fish Hyperopisus bebe (Mormyriformes) and the Patagonian tooth-fish Dissostichus eleginoides (Notothenioidei). We recommend the use of this non-destructive technique in the study of teeth in extant as well as extinct ichthyophagous teleosts, especially when fossil material is too fragile for sectioning.