How well do you know the human skull?

The Skull: Structure, Bones, and Functions

• The skull is a bony structure that protects the brain and houses sensory structures such as the eyes, ears, nose, and mouth.

• The human skull consists of three parts: the neurocranium, sutures, and facial skeleton, which includes the mandible.

• The neurocranium forms the protective cranial cavity that surrounds and houses the brain and brainstem.

• Except for the mandible, all of the bones of the skull are joined by sutures, which are synarthrodial joints formed by bony ossification.

• The human skull is generally considered to consist of 22 bones: 8 cranial bones and 14 facial skeleton bones.

• The skull contains sinuses, air-filled cavities known as paranasal sinuses, and numerous foramina, which are openings in the skull.

• The skull also contains many processes, including the mastoid process and the zygomatic processes.

• The skulls of fishes are formed from a series of loosely connected bones, while birds have a diapsid skull.

• Living amphibians typically have greatly reduced skulls, with many of the bones either absent or wholly or partly replaced by cartilage.

• The skull is a complex structure that develops through both intramembranous and endochondral ossification.

• Craniosynostosis is a condition in which one or more of the fibrous sutures in an infant skull prematurely fuses, leading to an abnormal head shape and abnormal facial features.

• Injuries to the brain can be life-threatening, and raised intracranial pressure can cause herniation of the brain out of the foramen magnum, resulting in significant brain damage or death unless an urgent operation is performed to relieve the pressure.Skull Anatomy and Its Significance

• Skull operations like trepanning were performed in the past, and some patients survived for many years afterward.

• Nowadays, a craniectomy is a common skull procedure that involves the removal of a portion of the skull bone.

• In 2013, the first successful skull replacement using a 3D-printed polymer implant was performed in the US.

• A Dutch woman also underwent a complete cranium replacement with a 3D-printed plastic insert.

• A study conducted in 2018 suggested that immune cells combined with the bone marrow reach the areas of inflammation after a brain injury through tiny channels in the skull.

• Surgical alteration of sexually dimorphic skull features is carried out as part of facial feminization surgery for transgender people.

• Artificial cranial deformation was a historical practice of some cultures that used cords and wooden boards to alter the shape of an infant's skull.

• Forensic scientists and archaeologists use skull and teeth features to estimate a person's life history and origin.

• The theory of phrenology, which attempted to show that specific features of the skull are associated with certain personality traits, is now considered pseudoscientific.

• In adulthood, male skulls tend to be larger and more robust than female skulls, which are lighter and smaller.

• Male skulls can have more prominent supraorbital ridges, a more prominent glabella, and more prominent temporal lines than female skulls.

• The cephalic index is the ratio of the width of the head to its length, and it is used to categorize animals, including humans.