Anatomy of the Skull: Sutures and Bones

Cranial Sutures

• There are four major sutures: sagittal, coronal, squamous, and lambdoidal.
• Sagittal suture: the joint between the two parietal bones.
• Coronal suture: the joint between the frontal bone and the parietal bones.
• Squamous suture: the joint between the parietal and temporal bones.
• Lambdoidal suture: the joint between the parietal bones and the occipital bone.

Cranial Features

• Supra-orbital notch or foramen: located in the frontal sinus.
• Parietal foramen: a distinct feature of the parietal bone.
• Occipital condyle: a feature of the occipital bone.
• Styloid process and zygomatic process: both are part of the temporal bone.
• Sphenoid bone: composed of several parts, including the sella turcica.
• Ethmoid bone: composed of three parts - perpendicular plate, cribriform plate, and ethmoid labyrinth.

Zygomatic Bone

• Zygomatic bone: composed of a temporal process, frontal process, and zygomatic arch.
• Temporal process and frontal process: both are parts of the zygomatic bone.

Mandible and Cranial Fossae

• Condylar process and coronoid process: both are part of the mandible.
• Mandibular foramen: a feature of the mandible.
• Vault of the Skull: a general term for the cranial structure.
• Middle cranial fossa: created by the sphenoid, temporal, and parietal bones.
• Posterior cranial fossa: formed by the sphenoid, temporal, and occipital bones.

Orbital and Nasal Features

• Orbital opening: composed of several features, including the supraorbital notch (foramen), infraorbital groove and canal, nasolacrimal canal, superior orbital fissure, inferior orbital fissure, and optic canal.
• Nasal vestibule: connects to the posterior nasal aperture (choana).
• Lateral wall of nasal cavity: composed of nasal conchae and nasal meatus.