Differences in tooth wear as an indicator of changes in jaw movement in the guinea pig Cavia porcellus.

Patterns of tooth wear have frequently been used to make inferences about jaw movements and tooth use in modern and extinct mammals. However, there has been relatively little experimental work to define the limits of usefulness of tooth wear studies. In the present study, electrolytic lesions in the left trigeminal motor nucleus of five guinea pigs resulted in significant changes of jaw movement. Scanning electron microscopy revealed significant differences in tooth wear between the lesion and non-lesion sides of these animals. Control animals showed no significant differences in tooth wear between right and left sides. The differences in tooth wear in the experimental animals were readily interpretable in terms of the induced changes in jaw movement.