Dissostichus eleginoides, Smitt, 1898

Germain, Damien, Mondéjar-Fernández, Jorge & Meunier, François J., 2016, The detection of weakly developed plicidentine in teleost teeth using 3 D tomography, Cybium 40 (1), pp. 75-82 : 80

Dissostichus eleginoides

Virtual cross sections show that plicidentine is composed of primary folds ( Fig. 5C, D ) that look like those described in the teeth of H. aimara and L. piscatorius ; these folds are limited to the basal third of the pulp cavity. Externally ridges are apparent on the free surface of the tooth ( Fig. 5D ). The pulp cavity is perfectly circular in section above the longest folds in the teeth (not illustrated). Dentine shows thin perforations ( Fig. 5D ) and/or canals ( Fig. 5E ). This organisation corresponds to a specific variety of dentine named either “vasodentine”, when odontoblastic canaliculi are absent, or “osteodentine” when they are present (see a.o. Lison, 1954; Bradford 1967; Herold, 1970; Schmidt, 1971); however, an histological study on ground sections is necessary to obtain more accurate detail on this dentine tissue, and to check whether odontoblastic processes are present or not.

Figures

Figure 5. - Dissostichus eleginoides (Nototheneidae); tomographic imaging of the anterior por- tion of the left premaxilla. A: Virtual model of the whole premaxilla (pmx) showing the exter- nal aspect of three caniniform teeth with external basal ridges (arrowheads); a fourth broken tooth shows ridges in the pulp cavity (white arrow); B: Virtual model of the premaxilla (bo) with axial section of the two widest caniniform teeth that show dentine folds in the pulp cavity (black arrowhead); folds are also shown in the broken tooth (white arrowhead); C: Virtual cross section in the tooth base at the level of the vascular aperture showing folds in the pulp cavity (white arrows); D: Virtual cross section, lightly above the previous level in C, showing dentine folds (white arrows) and external ridges (white arrowheads); the dentine core (de) of the tooth is perforated; E: Virtual axial section of the biggest tooth showing thin cavity and canals in the dentine (de); the tooth is covered by a thin enameloid layer; white arrowheads point to folds in the pulp cavity (pc). Scale bars:A, B = 5 mm; C, D = 2 mm; E = 1 mm.