Un nuovo metodo basato sull'analisi virtuale 3D dei molari primi per la sistematica evolutiva umana

Teeth play a fundamental role in human evolutionary systematics because each species has different morphological and morphometric characteristics of the dentition. In morphometric analyses the information available from the two basic diameters (bucco-lingual and mesio-distal) is limited. Therefore some authors have used 2D imaging analysis or 3D dental models. At present, however, there are no standard orientation procedures or analytical methods that are valid for worn teeth. In this paper we present a new method of 3D analysis of first molars with a standardized orientation system and a comparative dental analysis. The proposed geometric orientation system is based on three points identified on the cervical line. The morphometric analysis of the orientated teeth is based on virtual sections of the dental crown for the first 4 mm beginning from the cervical line. This method was tested by principal components analysis. It correctly separated Neanderthal and modern human teeth and allowed us to classify two specimens of uncertain attribution. In addition to being based on an objective criterion of comparison the method maintained its power of taxonomic discrimination even when the crown height was reduced to 3 mm by wear.