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The use of teeth as tools for manipulating objects and simple food-processing methods was common among prehistoric and modern hunter-gatherer human populations. Paramasticatory uses of teeth frequently produce enamel chipping and distinctive types of dental wear that can readily be related to specific tool functions. In particular, the presence of unusual occlusal wear areas (named para-facets) on maxillary teeth of prehistoric, historic and modern hunter-gatherers has been associated with cultural habits involving extensive use of teeth (Fiorenza et al., 2011; Fiorenza and Kullmer, 2013). However, Sarig and Tillier (2014) believe that this wear had been caused by pathological occlusal relationships rather than by the use of teeth as tools. In this contribution, we show how occlusal contacts are created and how it is possible to distinguish between masticatory and non-masticatory wear facets by using an innovative digital approach called Occlusal Fingerprint Analysis. Statistical results from the analysis of comparative modern samples clearly demonstrate that described para-facets in Skhul and Qafzeh could not have been produced by dental occlusal anomalies such as malocclusions and crossbites. Moreover, dental pathologies in prehistoric humans were extremely rare. Only with the adoption of the modern lifestyle between 18th and 19th centuries, did the emergence of malocclusions become significantly more common. Because more than 50% of the Skhul and Qafzeh individuals analysed in our study are characterised by this distinctive type of wear, it is highly unlikely that their para-facets occurred as a result of dental pathologies.

The mastication of tough and hard foods combined with the extensive use of teeth as tools, have been considered possible antemortem causes in determining enamel microfractures of the tooth crown. This phenomenon, known as dental chipping, has been found in different fossil hominins and in several pre-historic and historic human populations who adopted different subsistence strategies. However, little is understood of the mechanism, function and the formation of dental chipping. In this study we analyze the maxillary molar wear areas associated with dental chipping (and named para-facets) of several hunter–gatherer specimens, using the Occlusal Fingerprint Analysis method. We employ three-dimensional digital models of tooth crowns created by surface scanning of dental replicas, to analyze the dip and dip directions of normal occlusal wear areas and para-facets. This allows us to reconstruct the jaw movements responsible for the creation of para-facets, and investigate whether they are produced during normal mastication or not. Vectors of the para-facets do not show any preferred direction and are distributed randomly as visualized by the occlusal compass, displaying significant differences with the major jaw movements in action during the normal chewing cycle. More importantly, no antagonist contacts in the lower teeth are associated with the para-facets of the upper teeth. This excludes the possibility that the para-facets are created during normal mastication. We therefore suggest that this unusual type of tooth wear is mainly due to attritional and abrasive contacts generated through daily task activities for foods processing and/or manufacturing of objects.