ch1 skull

Cranium

The skull; consists of 22 bones, excluding the ossicles of the ear.

Calvaria

The upper domed part of the cranium that covers the cranial cavity.

Viscerocranium

The lower anterior part of the skull that includes the facial skeleton.

Sutures

Immovable joints that connect the bones of the skull.

Mandible

The movable bone that forms the lower jaw.

Frontal Bone

The bone that forms the forehead and the superior part of the orbit.

Zygomatic Bone

The cheekbone that forms the lower lateral rim of the orbit.

Nasal Bone

Paired bones that form the bridge of the nose and articulate with the frontal bone.

Maxillae

Paired bones that form the upper jaw and part of the orbit.

Temporal Bone

Bone contributing to the lower portion of the lateral wall of the cranium.

Occipital Bone

Bone that forms the posterior base of the cranium and contains the foramen magnum.

Pterion

The area where the frontal, parietal, sphenoid, and temporal bones meet.

Inferior Nasal Conchae

Paired bones that form the lateral walls of the nasal cavity.

Vomer

Unpaired bone that forms part of the nasal septum.

Occipital Condyles

Rounded structures that articulate with the atlas (C1) vertebra.

Carotid Canal

Opening for the internal carotid artery to enter the skull.

Sella Turcica

The depression in the sphenoid bone that houses the pituitary gland.

Cerebrospinal Fluid (CSF)

Clear fluid that surrounds the brain and spinal cord.

Meninges

Three protective membranes surrounding the brain and spinal cord: dura mater, arachnoid mater, pia mater.

Dura Mater

The tough outer layer of the meninges.

Arachnoid Mater

The delicate middle layer of the meninges.

Pia Mater

The thin inner layer of the meninges that adheres closely to the brain.

Extradural Space

Potential space between the dura mater and the skull that can become filled with fluid.

Subdural Space

Area between the dura mater and the arachnoid mater, clinically not a true space.

Subarachnoid Space

Real space between the arachnoid mater and pia mater, containing CSF.

Hydrocephalus

Condition characterized by an accumulation of CSF in the ventricles of the brain.

Craniosynostosis

The premature fusion of cranial sutures affecting skull shape.

Occipital Protuberance

Midline projection on the occipital bone; marks external surface.

Mental Protuberance

Midline swelling on the body of the mandible.

Temporomandibular Joint

Joint formed between the mandible and temporal bone.

Articular Tubercle

Projection at the anterior edge of the mandibular fossa of the temporal bone.

Mental Foramen

Opening on the anterior surface of the mandible for nerves and vessels.

Supraorbital Foramen

Opening in the frontal bone above each orbit.

Glabella

Smooth area located between the superciliary arches.

External Acoustic Meatus

Canal leading to the inner ear, visible on the lateral surface of the temporal bone.

Pterygoid Processes

Processes of the sphenoid bone that extend downward.

Olfactory Nerve

Cranial nerve I; responsible for the sense of smell.

Foramen Ovale

Opening in the sphenoid bone that allows passage of the mandibular nerve.

Foramen Rotundum

Opening for the maxillary nerve in the sphenoid bone.

Foramen Spinosum

Opening that allows passage of the middle meningeal artery.

Jugular Foramen

Opening for the internal jugular vein and cranial nerves IX, X, and XI.

Internal Acoustic Meatus

Passage for the facial and vestibulocochlear nerves.

Transverse Sinus

Venous sinus that drains blood from the brain.

Sigmoid Sinus

Venous sinus leading to the internal jugular vein.

Coronal Suture

Suture between the frontal and parietal bones.

Sagittal Suture

Suture between the two parietal bones.

Lambdoid Suture

Suture between the parietal and occipital bones.

Bregma

Junction of the coronal and sagittal sutures.

Lambda

Junction of the sagittal and lambdoid sutures.

Sphenoid Bone

Bone with a central body and wings that forms part of the cranial base.

Epidural Hematoma

Bleeding between the dura mater and skull, often due to traumatic injury.

Subdural Hematoma

Collection of blood between the dura and arachnoid mater.

Lacrimal Bone

Bone forming part of the medial wall of the orbit.

Palatine Bone

Bone forming the hard palate and part of the nasal cavity.

Infraorbital Foramen

Opening below the orbit in the maxilla.

Zygomatic Arch

Bony arch formed by the zygomatic bone and the zygomatic process of the temporal bone.

Mastoid Process

Bony prominence of the temporal bone that serves as a muscle attachment.

Condylar Process

Part of the mandible that articulates with the temporal bone.

Hard Palate

The bony top of the mouth formed by the maxillae and palatine bones.

Nasion

Bridge of the nose; junction of nasal bones and frontal bone.

Piriform Aperture

The teardrop-shaped opening of the nasal cavity.

Alveolar Process

The bony ridge in the mandible and maxilla that contains the teeth.

Temporalis Muscle

Muscle responsible for closing the jaw at the temporomandibular joint.

Cerebellum

Region of the brain located under the cerebrum; responsible for coordination.

Frontal Crest

Midline projection from the frontal bone for attachment of falx cerebri.

Crista Galli

Bony ridge of the ethmoid bone that serves as an attachment for the falx cerebri.

Lesser Wing of Sphenoid

Part of sphenoid that forms the boundary between the anterior and middle cranial fossae.

Greater Wing of Sphenoid

Part of the sphenoid bone that contributes to the lateral wall of the skull.

Petrous Part of Temporal Bone

Wedge-shaped portion of the temporal bone containing structures of the inner ear.

Zygomaticofacial Foramen

Opening on the zygomatic bone for nerves and vessels.

Nasal Region

Facial region that includes the structures of the nose.

Bony Nasal Septum

Dividing wall of bone in the nasal cavity.

Orbit

The bony cavity containing the eye.

Neurocranium

The part of the skull that encases the brain, consisting of eight bones.

Basilar Part of Occipital Bone

Part of the occipital bone that articulates with the sphenoid bone.

Lateral Pterygoid Muscle

Muscle that aids in the movement of the jaw.

Ptyergoid Hamulus

Hook-like projection at the end of the medial pterygoid process.

Saggital Suture

Suture between parietal bones, running along the midline of the skull.

Basilar Suture

Suture connecting the occipital bone to the sphenoid bone.

Junction Of Cranial Fossa

Connective region where anterior, middle, and posterior fossae meet.

Fornix

Arching structure in the brain, part of the limbic system.

Choroid Plexus

Network of blood vessels that produce cerebrospinal fluid.

Falx Cerebri

Dural fold separating the two cerebral hemispheres.

Tentorium Cerebelli

Dura mater fold that separates the cerebellum from the cerebrum.

Endocranium

The inner layer of the cranial cavity that houses the brain.

Transverse Sinuses

Venous sinuses that run horizontally at the base of the skull.

Auditory Tube

Tube connecting the middle ear to the pharynx.

Acoustic Meatus

Opening into the ear canal.

Vasa Recta

Small blood vessels associated with the particles of the cranial cavity.

Cranial Nerves

Twelve pairs of nerves that arise directly from the brain.

Tympanic Membrane

Membrane separating the external ear from the middle ear.

Cochlea

Spiral structure in the inner ear responsible for hearing.

Cribriform Plate

Thin bone allowing passage of olfactory nerves.

Olfactory Bulbs

Bulbs that receive signals from olfactory senses, located at the base of the brain.

Temporomandibular Joint Dysfunctions

Disorders affecting the jaw joint and surrounding muscles.

Occipitomastoid Suture

Suture connecting the temporal and occipital bones.

Sigmoid Sinus

Venous sinus that drains the brain into the internal jugular vein.

Somatic Nerves

Nerves that control voluntary muscle movements.

Accessory Nerve

Cranial nerve XI responsible for shoulder and neck movement.

Meningeal Arteries

Arteries that supply blood to the meninges.