mandibulars

Mandibulars is a relatively uncommon plural form that generally refers to mandibular structures—the mandibles or lower jaw components of jawed animals. In standard terminology, the noun form mandibles is preferred, and mandibular is the adjective. The plural mandibulars appears mainly in specific taxonomic or anatomical contexts, but it is not widely used in contemporary anatomy.

In vertebrates, the mandible consists of paired lower jawbones that bear the teeth and form the primary chewing mechanism. In mammals, each side is a dentary bone, and the two sides meet at the mandibular symphysis during development. The mandibles articulate with the skull at the temporomandibular joints, enabling complex movements for biting and grinding. The chewing action is driven by muscles such as the masseter, temporalis, and pterygoids.

In many invertebrates, particularly insects and crustaceans, mandibles are mouthparts derived from different evolutionary origins. These mandibles function as cutters, crushers, or grinders and play a key role in feeding and defense. While they share a general role in food processing, they are not homologous to vertebrate mandibles.

Development and evolutionarily, jaws originate from the first pharyngeal arch. In vertebrates, jaw evolution is linked to changes that later contributed to the emergence of the middle ear bones in mammals, with some skeletal elements repurposed during evolution.

Clinically, the mandible is important in dentistry and medicine: fractures, dental occlusion, and temporomandibular joint disorders can affect function and aesthetics. Etymologically, mandibula means “jaw” in Latin, with mandibular as the related adjective.