Lecture 9 & 10 Flashcards
Notes on the skull
Has 22 bones forming the bony framework of the head
The head is firmed mainly by the skull with the brain and it’s covering enclosed in the cranial cavity
United at immobile fibrous joints called sutures
Cranium bones
Frontal bone
Occipital bone
parietal bone
ethmoid bone
temporal bone
sphenoid bone
Facial bones
Zygomatic
vomer
mandible
Palatine
Maxilla
nasal
lacrimal
inferior nasal Conchae
Composition of the cranial cavities
- Consists of the base and the vault
2) Contains the brain meninges
portions of the cranial-nerve
blood vessels and nerves

Short note on the base of the cranial cavities
Has three depressions,
which are
the anterior cranial fossae,
middle cranial fossae
the posterior cranial fossa
The vault
Dome shaped and consists of the
Parietal
Frontal
Occipital
Short notes on the Hyoid
1) Consists of the greater and lesser horn and the body
2) U shaped
3) It is located between the voice box and mandible
4) Only bone in body that has no articulation
5) connects the floor of the oral cavity in the pharynx
different of sutures
Lamoid
Coronal
Sagittal
Lamoid suture
Arches across the poster surface of the skull, connects the occipital bone with the two parietal bones 
Coronal suture
Attaches frontal to the parietal bone
Saggital suture
Extend from the Lamoid suture to the coronal suture between the parietal bones
Obirtal cavities
Lies in the upper half of the face
Formed by 7 bones
And 4 bones
7 bones that form the orbital cavities
Frontal
Sphenoid
Maxillary
Ethmoid
Lachrymal
Zygomatic
Palatine
4 walls that form the orbital
Roof (frontal and the sphenoid )
Lateral ( zygomatic, sphenoid)
Medial ( maxilla, lacrimal, ethmoid)
Floor( maxilla, zygomatic)
nasal cavities : location
Between the orbits and divided into the right and left cavities by the nasal septum
Structure of the nasal cavities
Lateral wall : curved bone called conchae
Medial wall: formed by the nasal septum
Roof: narrow, contains smell receptors
Floor: wide, separates nose from the mouth
Lateral wall of nasal cavities
Maxilla
Lacrimal
Ethmoid
Inferior nasal conchae
Medial wall of the nasal cavities
Perpendicular platter of the ethmoid
Vomer
Roof of the nasal cavities
Nasal bone
Frontal bone
Ethmoid
Sphenoid
Floor of the nasal cavities
Palatine
Bone
Maxilla
Paranasal sinuses:
Air filled mucous lined spaces within skull bones that are continuous with nasal cavities
Location of the paranasal sinuses
At the sphenoid, ethmoid, frontal bone and paired palatine bones and maxilla
Functions of the paranasal bone
Make skull lighter
Enhance voice resonance
Maxilla sinuses
Largest and lowest sinus
Clinically important because it’s drainage lies superior near the roof
Frontanelles
Newborns cranial bones are separated by large Membranous and Unassified gap
4 large frontanellous
Anterior
posterior
anterolateral
posterior-lateral
Functions of the frontanellous
Allows hear to deform as bones overlap during its passage through the birth canal
Rapid growth and expansion of the infants brain 
Functions of the skull
Protects and stabilises position of the brain cranial nerves and blood vessels
How to surface provides a large area attachment for muscles
Provides framework and support