Dissostichus eleginoides, Smitt, 1898

Texereau, Megann, Germain, Damien & Meunier, François J., 2018, Comparative histology of caniniform teeth in some predatory ichthyophagous teleosts, Cybium 42 (1), pp. 75-81 : 78

Dissostichus eleginoides

In this fish, no odontoblastic process is observed on any longitudinal or transverse histological section ( Fig. 5D, E ). However, dentine shows thin perforations ( Fig. 5B ) and/ or canals ( Fig. 5C ). Several anastomosing vascular canals leave the pulpar cavity following a direction parallel to the main axis of the tooth ( Fig. 5D ). The mere presence of a vascular system in the tooth thickness and the absence of odontoblastic canaliculi are characteristic of a specific variety of dentine, the vasodentine ( Lison, 1954; Herold, 1970). On the virtual sections, a plicidentine composed of simple folds is present in the basal third of the pulpar cavity ( Fig. 5 A-C). Meanwhile, enameloid is present in a thin collar at the periphery of the tooth and thickens toward the top forming the cap acrodine ( Fig. 5C ).

Figures

Figure 5. – Dissostichus eleginoïdes (Nototheneidae). A: Virtual model of the whole left premaxilla (pmx) showing the external aspect of the three caniniform teeth with external basal ridges (arrowheads); a fourth broken tooth shows folds in the pulpar cavity (white arrows); B: Virtual cross-section showing dentine folds (white arrows) and external ridges (white arrowheads); the dentine (de) core of the tooth is perforated; C: Virtual axial section of the largest tooth showing thin cavity and canals in the dentine (de); the tooth is covered with a thin enameloid (en) layer and forms a cap at the apex of the tooth; white arrowheads point to fold in the pulpar cavity (pc); D, E: Detail of a lon- gitudinal (D) and transverse (E) sections (MNHN-Histos 2344 (D), MNHN-Histos 2342 (E) in natural transmitted light) showing the presence of many vascular canals anastomosed (white arrows); no odontoblastic tubules is present; the tooth is covered with a thin enameloid layer (en). Scale bars:A = 5 mm; B = 2 mm; C = 1 mm; D = 10 μm; E = 40 μm.