Head and Neck Anatomy Flashcards
How is the development of the skull related to the development of the brain?
The development of the skull is driven by the development of the brain.
Functional matrix theory.
Why is there such a disproportionately smaller brain case relative to the face at birth?
Functional driver of facial skeleton is different to cranial skeleton.
How is the cranial cavity divided?
3 fundametal parts:
Anterior cranial cavity
Middle cranial cavity
Posterior cranial cavity
What are the important foramina of the cranial cavity?
Foramen magnum
How is the spherical shape of the brain case produced?
Flat bits produced denovo from connective tissue via Intramembranous ossification.
Endochondral ossification produces the base of the brain case. (this continues until about the age of 25)
What is the purpose of CSF?
It protects the brain and provides padding for it during collisions.
How does the brain develop in young children?
Islands of bone form and then fuse
What embryological structures form the cranial bones and which form the facial bones?
Cranial bones: Formed by the brain & vertebral development.
Facial Bones: formed by the foregut during development (via the pharyngeal arches)
Which directions are facial bones strong?
Vertically, they are weak vertically
What is the job of pharyngeal arches?
Each one is reponsible for the formation of one part of the head.
What is the job of the 1st pharyngeal arch?
1st pharyngeal arch is important for formation of the bones of the jaw and maxilla
Important to know about pharyngeal arches:
Each arch is highly specific for the structure that it ends up forming.
How are facial bones arranged?
They are designed to create the maximum surface area of mucosa for air to travel for its air conditioning job.
What are the muscles that close the jaw called?
The muscles of mastication.
Where do the muscles that close the jaw come from?
The 1st pharyngeal arch (which is why they are supplied by the trigeminal nerve)