Anatomy and Cell Biology 3319 Lecture Notes - Lecture 18: Anterior Cranial Fossa, Infraorbital Foramen, Sphenoidal Sinus
1 May 2018
School
Department
Professor
Lecture 018: Osteology of the Skull; Cranial Fossae and Foramina
Objective
● Individual Bone Features:
○ Describe the major feature of the maxilla
○ Describe the major feature of the sphenoid bone
○ Describe the major feature of the ethmoid bone
● Orbit
○ Name the bones of the orbit
● Cranial cavity
○ Identify the bones that contribute to the 3 cranial losses
○ Identify the 11 major foramina of the cranial fossae and the structures that
pass through them
○ Describe the foramina of the inferior surface of the skull
Maxilla
● Keystone bone of the face
○ Lots of other bones are connected to it
○ Very prominent
● Contains the upper teeth
● Has processes to articulate with the other bones
○ Frontal bone, zygomatic bone
● Space for the nasal cavity
● Infraorbital foramen
○ V2 (maxillary division of the trigeminal nerve)
○ Sensory ONLY nerve to the teeth, some of the sinus (empty space within
a bone), and the surface skin around the maxilla (terminal branches)
■ Pain (toothaches)
● Palatine processes (lateral projections)
○ Joined by the palatine bone at the posterior end of the mount
○ Makes up the roof of the mouth
○ Bones grown and fuse during fetal development (suture midline and
anterior)
○ Cleft palate
■ When the palatine process don’t fuse correctly
■ Make it so that the oral cavity and the nasal cavity are not walled off
from each other
■ Easily repaired
Sphenoid Bone
find more resources at oneclass.com
find more resources at oneclass.com
● Only a small proportion is visible externally
● Most is internal
● Looks like a bat
○ Has “wings” (greater and lesser)
● Sella turcica
○ Looks like a saddle
○ Has a depression (pituitary fossa) that the pituitary glands sits on
● Cavernous sinus
○ Venous drainage on either sides of the pituitary glands
○ Have structures that passes through
● Superior orbital fissure
○ Long gash like opening
○ Going towards the eye
○ Several nerves controlling eye movement passes through here
● Optic canal/foramen
○ Where the optic nerve passes
● 3 openings in a row
○ Foramen rotundum
■ Anterior to the foramen ovale
■ V2 (maxillary division of the trigeminal nerve)
○ Foramen ovale
■ Large oval shape, middle one
■ V3 (mandibular division of the trigeminal nerves)
○ Foramen spinosum
■ Middle meningeal artery passes through
● Pterygoid processes
○ Muscle of mastication attach to these
● There is also a sinus in the middle of the bone
○ Acts to decrease weight
Ethmoid Bones
● Very light because of the ethmoid air cells (sinuses)
● Makes up the nasal cavity
● Crista galli
○ Projection into the cranial cavity
● Cribriform plate
○ Where the openings for the nerve filaments for the olfactory nerves pass
through
● Septum
○ Divides the two sides of the nasal cavity
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Lecture 018: osteology of the skull; cranial fossae and foramina. Describe the major feature of the maxilla. Describe the major feature of the sphenoid bone. Describe the major feature of the ethmoid bone. Identify the bones that contribute to the 3 cranial losses. Identify the 11 major foramina of the cranial fossae and the structures that pass through them. Describe the foramina of the inferior surface of the skull. Lots of other bones are connected to it. Has processes to articulate with the other bones. V2 (maxillary division of the trigeminal nerve) Sensory only nerve to the teeth, some of the sinus (empty space within a bone), and the surface skin around the maxilla (terminal branches) Joined by the palatine bone at the posterior end of the mount. Makes up the roof of the mouth. Bones grown and fuse during fetal development (suture midline and anterior) When the palatine process don"t fuse correctly.
