Comparison of skull shape in brachycephalic and mesaticephalic dogs using three-dimensional morphometric techniques / Estudo comparativo da forma do crânio de cães braquicefálicos e mesaticefálicos por meio de técnicas de morfometria geométrica em três dimensões

AUTOR(ES)

Fernanda Appollo-Hofmann

DATA DE PUBLICAÇÃO

2009

RESUMO

The observed variation in skull conformation of the breeds of domestic dogs is the result of selection during domestication process and it provide information about the patters of interaction among the different parts that constitutes this structure. Qualitative studies published in the literature shown that brachycephalic breeds have the highest variability in skull shape when compared to mesaticephalics. In this study, different regions of the skull of specimens belonging to both groups were analyzed quantitatively, using geometric morphometric techniques. Fifty-two skulls and 57 landmarks were selected and digitalized to perform a 3-D reconstruction of the skulls. Multivariated analyses over the coordinates were used to analize and quantify shape differences between the two groups. Patterns of asymmetry were explored for both, the cranium and mandible, analyzing separately six regions of interest: teeth contact between upper and lower jaw; braincase; mandibular fossae; condilar processes; zygomatic arches and coronoid processes. To evaluate covariance patterns the regions were analyzed in pairs: teeth contact between upper and lower jaw; mandibular fossae and condilar process; zygomatic arch and coronoid process; upper fourth premolar and lower first molar; cranium and mandible. The statistical analyses indicated significant differences between the brachycephalic and mesaticephalic groups for asymmetry at the different regions of the skull and teeth contact between upper and lower jaw. For the covariance patterns there is statistical significant difference for teeth occlusion between upper and lower jaw; skull and jaw; upper fourth premolar and lower first molar relationship. In conclusion, the main differences are located in the rostrum contact between upper and lower rostral teeth and upper fourth premolar and lower first molar. These results suggest that the highest shape variability in the skull of braquicephalics dogs is concentrated in structures that are used in the mastication, without differences at the caudal region of the jaws.

ASSUNTO(S)

geometric morphometrics asymmetry cães malocclusion morfometria geométrica assimetria dogs skull crânio maloclusão

Documentos Relacionados

• Estudo comparativo da sintopia do encéfalo de cães dolicocefálicos, mesaticefálicos e braquicefálicos, por meio de macroscopia e imagens tomográficas
• Three-dimensional stellarator codes
• Three-dimensional ontogenetic shape changes in the human cranium during the fetal period
• Three-Dimensional Imaging In Surgery
• Three-dimensional flow calculations of axial compressors and turbines using CFD techniques.