Quantitative three-dimensional topography in taxonomy applied to the dental morphology of catarrhines

Abstract

This paper presents a new aspect in studies of dental morphology based exclusively on 3D topographical analysis. Our method was applied to a set of 20 unworn upper second molars belonging to seven extant catarrhine genera. From a geometrical analysis of the polygonal grid representing the shape of each tooth, we propose a 3D dataset that provides a detailed characterization of the enamel morphology. In this article, we present a taxonomic application of our method using the example of inclination. Our initial results show intergeneric variation for the selected topographic parameter and its relevance to taxonomic analyses of extinct primates. More generally, our analysis of irregular grid patterns in 3D digital models supplied new parameters and enabled a review of the data classically studied in dental palaeoanthropology, with potential implications for taxonomic, phylogenetic, functional and developmental studies.