Shovel-shaped incisors (or, more simply, shovel incisors) are incisors whose lingual surfaces are scooped as a consequence of lingual marginal ridges, crown curvature or basal tubercles, either alone or in combination.
Shovel incisors are relatively more common in East Asian populations, particularly among certain Japanese and Native American populations. The trait is rare or not present in European and African populations. In some instances, incisors can present a more pronounced version of this called double shovel-shaped. The differences observed in tooth morphology is believed to be partly determined by genetics. When present, shovel-shaped incisors can indicate correlation among populations and are considered to be one of the non-metric traits in osteology. The characteristic could also be attributed to hormones, duration of development, and the capacity of the maxillary dental arch.
The shovel-shaped dental characteristic can also be traced back to Homo erectus and in Neanderthals. The morphology of Neanderthal's anterior teeth has been seen as an adaptation to the heavy use of their canines and incisors in processing and chewing food, and the use of their teeth for activities other than feeding.
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- Clement, Anna F.; Hillson, Simon W.; Aiello, Leslie C. (2012-01-01). "Tooth wear, Neanderthal facial morphology and the anterior dental loading hypothesis". Journal of Human Evolution. 62 (3): 367–376. doi:10.1016/j.jhevol.2011.11.014.