8.2 - 8.3 Overview
8.2
Where are the cranial vs facial bones located and what are they?
Cranial bones
Form the cranium / skull
Eight bones form a roof and a base
The roof of the cranium is the called the calvaria and is composed of the superior part of the frontal bone, the parietal bones, and a small part of the occipital bone
The base of the cranium is composed of portions of the frontal, ethmoid, sphenoid, occipital, and temporal bones
Facial bones
Form the face
There are 14 facial bones
What are the 4 primary plates of the skull?
Frontal - makes up the front including the forehead
Parietal - top of skull
Temporal - sides of skull
Occipital - back of skull
Cleft lip and palate
Cleft lip - upper jaw components do not fuse as an embryo, causing the top lip to be split up to the nostril
Cleft palate - oral cavity and nasal cavity are not separated properly
What is a fossa
Contoured floor / depression
Where are the three cranial fossae?
The anterior cranial fossa is in the front
The middle cranial fossa is in the middle
The posterior cranial fossa is the furthest back
What is a skull suture?
Immovable fibrous joints that form the boundaries between cranial bones
Made of dense regular connective tissue
Where are the 4 sutures of the skull?
Coronal suture connects frontal and parietal bones
Lambdoid suture connects parietal and occipital bones
Sagittal suture connects right and left parietal bones
Squamous suture connects temporal and parietal bones on either side
8.3
What and where is the hyoid bone?
Supports your tongue and helps you speak and swallow
Below the mandible and doesn’t touch any other bone
If it is broken, it’s probably because someone strangled you
What are 2 interesting facts about the hyoid bone provided in class?
The human skull exhibits sexual dimorphism. Know 6 differences between the male and female skull
chin is more pointed on women and more square on men
mandible is more robust on men
men have larger mastoid process
mandibular angle is more obtuse on women
supraorbital margin is bigger and more blunt
frontal bone is more vertical in women and more sloped in men
What are fontanelles?
spaces that sutures fill
soft spot on baby’s head
allow skull bones to slide across each other during birth
How can the skull identify the age of a skeleton
How many skull sutures are completely closed