Distribución de Tensiones Durante la Mordida en la Mandíbula de Carnotaurus sastrei (Theropoda: Abelisauridae)

G.V. MAZZETTA; A.P. CISILINO; R.E. BLANCO

AMEGHINIANA

Asocición Paleontológica Argentina

Lugar: Buenos Aires; Año: 2004 vol. 41 p. 605 - 617

0002-7014

A computerised tomography scanning was used to generate a three-dimensional mandible reconstruction of the carnivorous dinosaur Carnotaurus sastrei. This non-invasive technique provides a suitable foundation for finite element modelling (FEM) of biological structures such as the one mentioned above. FEM is a numerical approach very appropriate to analyse the mechanical behaviour of the mandible, which in vivo is subjected to varying regimes of stress and strain. The model of the mandible was loaded in order to simulate six different conditions (ventrally directed static bite applied at the anterior, central, and posterior teeth; with and without axial traction of a hypothetical prey). The mechanical strength of the mandible was also studied through an estimation of the maximum bite force capable to withstand failure stress. The bilateral muscle-driven bite force of Carnotaurus (3341 N; estimated at the posteriormost teeth) would have been relatively weak in comparison with the one corresponding to extant carnivores.Principal stress magnitudes varied predictably for the studied loading conditions, with peak stresses found at the in tramandibular joint. When the effects of adductor muscle forces and reaction condylar forces are removed from the model, the maximum force withstood by the mandible may be up to 6.1 times higher than the estimated muscle-driven bite force. This does not suggest a mandibular design particularly strong in Carnotaurus.