Identification of Areca-catechu (betel nut) residues on the dentitions of Bronze Age inhabitants of Nui Nap, northern Vietnam

The dentitions of 31 individuals excavated from the Bronze Age site Nui Nap, Thanh Hoa province, Vietnam were examined for the presence of Areca catechu (betel nut) residues. The chief investigatory method involved GC/MS analysis of a dark reddish-brown stain commonly observed on the labial aspect of the anterior teeth of individuals from this site. The results of this work indicate that these teeth were stained by way of betel nut. enamel surface morphology and the distribution of staining suggests purposeful application of betel nut residues to the teeth, perhaps for aesthetic reasons.