prognathic

Prognathism is the forward projection of the jaw relative to the skull base. The term derives from Greek pro- meaning forward and gnathos meaning jaw. It is used to describe protrusion of either jaw and is commonly divided into mandibular prognathism (protruding lower jaw) and maxillary prognathism (protruding upper jaw). The opposite condition is retrognathism, in which the jaws are set back. In dentistry and anatomy, prognathism affects facial profile and dental occlusion.

In humans, modern Homo sapiens generally exhibit less prognathism than some extinct or archaic hominins, contributing to a flatter midface and reduced jaw protrusion. Nevertheless, variation exists across populations, with some individuals showing more pronounced mandibular or maxillary projection. Fossil evidence indicates that species such as Neanderthals had relatively pronounced prognathism compared with anatomically modern humans. Across mammals, prognathism reflects differences in feeding strategies and skull mechanics.

Clinically, prognathism can influence bite alignment, chewing efficiency, speech, and facial aesthetics. Management ranges from orthodontic treatment to orthognathic surgery, depending on severity and functional impact. Severe prognathism may be associated with syndromic conditions or hormonal disorders (for example, acromegaly) and may require multidisciplinary care. In scientific and evolutionary contexts, prognathism is used to describe jaw relationships and to compare craniofacial anatomy across species and populations.