Dental erosion in South Atlantic dolphins (Cetacea: Delphinidae): a macro and microscopic approach.

摘要

This paper evaluates the prevalence and macro and microstructural characteristics of dental erosion of teeth samples derived from 350 individuals of 10 species of marine delphinid cetaceans collected along the southern coast of Brazil. Results showed that out of the 10 species analyzed, half were diagnosed with dental erosion. The prevalence was low in Sotalia guianensis and Tursiops truncatus, two species with large sample sizes. On the other hand, the prevalence was moderate in Steno bredanensis, Pseudorca crassidens, and Orcinus orca, species with smaller sample sizes. From the results it can be concluded that the occurrence of erosion in animals from distinct geographic locations and collected in different years was not a regional or time frame-restricted event. Previous studies also showed that dental erosion in dolphins presented similar features to those seen in humans in relation to appearance and formation of cavities. Similarly to what has been documented in humans, in severe cases tooth morphology was affected and crown height was significantly reduced. Light microscopy revealed features compatible with demineralization of hard tissue as seen in humans, such as smooth surfaces and formation of reparative dentine as a biological response to compensate for loss suffered. Finally, micro-CT provided high-resolution images that contributed to qualitative characterization of dental erosion, having the distinct advantage of being nondestructive. This technique has been proven useful and a powerful tool in human dental research, with clear potential to be applied in other mammals.Digital Object Identifier http://dx.doi.org/10.1111/j.1748-7692.2012.00562.x