Pterion.
Where the temporal, sphenoid, parietal, and frontal bones meet. It overlies the middle meningeal artery; thus, injury to the pterion is a common cause of intracranial epidural hematoma.
Skull - Lateral View
Cranial bones
- Enclose and protect the brain
- Comprises the forehead and the superior portion of the eye orbit
- Comprises the superior portion of the lateral skull
- Only small portion visible in lateral view
- Gives rise to pterygoid processes
- Forms inferior boundary of lateral skull
- Squamous portion is area inferior to squamous suture
- Tympanic portion surrounds the external auditory meatus
- External auditory meatus is the external opening of the ear
- Mastoid process is the large bony projection near the occipital bone
- Styloid process is a long, pointy projection
- Mandibular fossa is a depressed area of the temporal bone that articulates with the mandible to form the temporomandibular joint
- Comprises posterior and inferior portion of cranium
Facial bones
- Form the face and protect the entrances to the oral and nasal cavities.
- Contributes to the lateral eye orbits and cheeks
- Forms the bony component of the external nose
- Contributes to the medial eye orbit, cheeks, and upper jaw
- Anterior nasal spine is the projection of the maxillae that contributes to the inferior border of the opening of the nasal cavity.
- Contributes to medial eye orbit
- Contributes to medial eye orbit
- Fossa for the lacrimal sac, through which tears pass from the eye to the nasal cavity. This connection explains why your nose runs when you cry.
- Bone of the lower jaw; it houses the lower teeth.
- Condyle (aka, head) articulates with the mandibular fossa of the temporal bone posteriorly
- Coronoid process provides an attachment site for temporalis, a powerful muscle of the jaw.
- Mandibular notch lies between condyle and coronoid process
- Ramus is the vertical portion
- Body is anterior and lateral base
- Angle lies between body and ramus, posteriorly
- Mental protuberance, which forms the chin
Four major sutures:
- Sutures are the immoveable joints between the skull bones.
- Lies between the frontal bone, anteriorly, and the parietal bones, posteriorly;
- Lies between the right and left parietal bones;
- Lies between the temporal and parietal bones.
- Lies between the parietal and occipital bones.
- Small, irregularly shaped bones that form between the major skull bones.
Pterion
- Where the temporal, sphenoid, parietal, and frontal bones meet
- Overlies the middle meningeal artery; thus, injury to the pterion is a common cause of intracranial epidural hematoma.
Additional Features:
Paranasal sinuses
- Spaces within the frontal, ethmoid, sphenoid, and maxilla; they are continuous with the nasal cavity (and are addressed in detail with the respiratory system).
- The zygomatic process, which is a projection of the temporal bone
- The temporal process, which is a projection of the zygomatic bone