Skull osteology

Which is the skull and which is the cranium

skull has mandible attached

What are 4 functions of the skull?

protect the brain

upper part of the alimentary (digestive system) and respiratory system (nose and mouth)

protective capsule for organs of sight, hearing and smell

close relationship with teeth and oral soft tissue

Name these structures and the cavities and role of the cavities

cranial cavity - encloses the brain

orbital cavity - encloses the eyes

nasal cavity - olfactory apparatus

passage way to respiratory system

hallow - paranasal sinuses 4 of them - help lighten the weight of the skull

allow air to circulate, contain mucus and vascularised so allow air to be warmed up before reaching the lungs, provide resonance to sound

How many bones is the skull made of?

23

What are the bones of the face and bones that are in contact with the brain called and what aree these further split into?

neurocranium - contact with the brain

viscerocranium - bones of the face

neurocranium is split into bones of the vault - which form the roof, while the bones of the base from the base of

What are the two roles of the cranial bone?

enclose the brain in the cranial cavity

provides sites of attachment for head and neck muscles

What are the 4 roles of the facial bones?

framework of the face

cavities for special sense organs, for sight, taste and smell

openings for air and food passage

sites for attachment for teeth and muscles of facial expression and muscles of mastication

What are the names of these 3 structures

projections in anatomy are known as?

procceses

Name these structures

mandibular angle connects the mandibular ramus and body of the mandible

alveolar margin provides sockets for the teeth - present as long as teeth are present

maxilla contributes to the lateral aspect of the nose and the upper jaw, floor of the nasal cavity adn floor of the orbital cavity

temporal bone on the lateral aspect

zygomatic arch connects the occipital bone to the zygomatic bone

Name these structures of the skull

Name these aspects of the skull (anterior view)

depression - lacrimal fossa holds the lacrimal sac

Name the facial bones

How do you describe a cavity?

roof, floor, lateral and medial wall

What are the structures on the roof of the orbit?

superiorly - orbital plate of the frontal bone

slit like structure - superior orbital fissure found in the lesser wing of the sphenoid bone, in the sphenoid bone there is another foramen - optic canal - where the optic nerve enters the retina of the eye

Describe the lateral wall of the orbital cavity

Describe the medial wall of the orbital cavity

frontal process of maxilla, the part of the maxilla joining the frontal lobe

Describe the floor of the orbital cavity

label these structures

Label this structure

what are the 4 regions of the temporal bone?

squamous region - lateral aspect

petrous region on the base of the skull

label these structures

mandibular fossa is where the mandibular condyle articulates

label this superior view and the important sutures

sutures are immovable joints

Name the structures on the posterior view?

What is the circled part of the brain and what is its significance?

pterion

weaker part of the skull as many bones join here, the bone in this region is very thin, therer is also an important artery running behind it

Name the 8 bones of the face?

which are paired and which aren’t

What are the 6 bones of the neurocranium?

through the incisive fossa, nerves which innervate the teeth

Name the labelled structures of the base of the cranium

muscles of the neck attached to the nuchal lines

foramen magnum - spinal cord

The cranial fossa is divided into what cranial cavities?

based on the part of the brain located in each cavity

anterior cranial fossa - forebrain

middle cranial fossa - midbrain

posterior cranial fossa - hindbrain

What are the structures found in the anterior cranial fossa

describe the structures in the middle crania fossa

sella turcica - pituitary gland is located

groove for the cavernous sinus is on the lateral aspect of the sell turcica

optical chiasma - the optic nerves cross each other leaving a groove

CFS otorrhea can happen if there is a fracture near the internal acoustic meatus

describe the sphenoid bone

body - central bit we have the sella turcica and optic canal

lesser wing

greater wing - foramen rotundum, ovale and spinosum

describe the structures in the posterior cranial fossa

Lebel this diagram

What forms the TMJ?

T MJ is formed by the mandibular condyle and the mandibular fossa

mandibular nerve enters the mandibular foramen

maxillary bone is more porous so anaesthetic can diffuse through the bone - can’t be done to the mandible

How is the neonatal skull different to the adult skull

the bones are separated from each other and not fully connected leading to fontanelle which is fibrous tissue present between bones, allows bones to overlap each other, they are growth sites

the

mastoid (left right movement and up and down) and styloid process not present - they develop during muscle attachment

skull is flat

the cranial is larger than the face

distance between mouth and orbit is small, as vertical growth of maxilla hasn’t occurred yet