In biology and medicine, the skull is a bony structure in the head of most vertebrates that supports the structures of the face and forms a protective cavity for the brain. The skull is composed of two parts: the cranium and mandible.

The cranium includes both the cranial vault—the upper portion—and facial bones, which include many of the more movable bones supporting both sides of the nose and mouth, such as zygomatic bones, maxillae, mandible (lower jaw), nasal bone and lacrimal bone. The cranium also contains sinuses that drain blood from the brain to keep it oxygenated.

The mandible is a bone in your mouth that helps you chew food. It consists of two portions: upper and lower dentures. Your upper teeth fit into your lower dentures like a lock-and-key system; when you close your mouth, your upper teeth rest on top of your lower dentures like a hinge would allow for movement between two pieces.

Last modified: October 2, 2022