Skull and muscles of mastication Flashcards
what does the neurocranium enclose
cranial cavity
what does the viscerocranium enclose
orbit, nasal and oral cavities
what are the 2 divisions of the neurocranium
calvarium and cranial base
what is the name of the meeting point between the coronal and saggital sutures
bregma
what is the name of the meeting point between the squamosal and coronal sutures
pterion
what is the name of the meeting point between the lamboidal and saggital sutures
lambda
before the cranial sutures fuse what are the membranes called
fontanelles
what is the purpose of fontanelles
allow flexibility of skull during childbirth
accomodates braingrowth
what results from premature fusion of coronal sutures
craniosynotosis
what is hydrocepahlus
increased pressure of fluid in the skull
what is the weakest point of the skull
pterion
what does the pterion overly
middle meningeal artery
what does the frontal bone form part of
the anterior cranial fossa and roof of orbit
what does the occipital bone form
part of the posterior cranial fossa
what passes in the hypoglossal canal
cranial nerve 7 , hypoglossal
what does the temporal bone form part of
muddle and posterior fossae
what is the sphenoid bone part of
anterior and middle cranial fossaw
where do the meninges attach
4 clinoid processes
what openings are in the sphenoid bones
optic canal, superior orbital fissure, foramen rotundum, foramen ovale
what is the ethmoid bone part of
the anterior crnial fossa
which part of the ethmoid bone has holes opening into the nasal cavity
cribriform plate
where are the upper teeth embedded
the alveolar ridge
what part of the skull does the maxilla belong
viscero cranium
describe the maxilla
floor of orbit
floor and lateral wall of nasal cavity
hard palate
what part of the cranium does the zygomatic belong
viscerocranium
what does the zygomatic articulate with
maxilla, sphenoid, frontal and temporal bones
what forms the zygomatic arch
zygomatic bone and part of the temporal bone
what is the zygomatic part of
lateral wall of orbit
lateral walls of temporal and infratemporal fossae
describe the palatine bone
floor of orbit
floor and lateral wall of nasal cavity
hard papalte
describe the lacrimal bone
medial wall of orbit
lateral wall of nasal cavity
describe the turbinate bones
lateral wall of nasal cavity
3 conchae project into the cavity on each side
nasal septum fivides
describe the nasal bone
forms bridge of nose
what does the nasal bone articulate with
frontal, maxilla and ethmoid
what is the vomer bone
part of the nasal septum
what does the vomer articulate with
maxilla, palatine, sphenoid and ethmoid
what makes up the nasal septum
ethmoid, vomer, cartilage
what is the vomeronasal organ
where the vomer meets the palate containing receptors for pheromones
what does tmj stand for
temperomandibular joint
what type of joint is the tmj
modified hinge synovial joint
describe the TMJ
head rotates on disc, head and disc translate on fossa
ie when opening the mouth, the head rotates as it and the disc move anteriorly toward the articular tubercle
what causes clicking and difficulty opening the jaw
the articular disc being displaced anteriorly
what happens in dislocation of the jaw
condyloid process dislocates anteriorly
muscles tighten and hinder repositioning
inability to close moth
how to reduce jaw dislocation
mandible is inferiorly translated and gently retracted into place
4 pairs of muscles of mastication
Masseter
Temporalis
Medial pterigoid
Lateral pterygoid
action of the muscles of mastication
MTM - elevate mandible
LP- depress mandible
innervation of the muscles of mastication
mandibular division of trigeminal V3
attachments and action of the masseter
zygomatic arch -> angle of mandible
elevate and protrude mandible
attachments and action of temporalis
temporal fossa -> coronoid process of mandible
elevate and retract mandible
attachments and action of the lateral pterygoid
Lateral pterygoid plate and sphenoid -> condyloid process and articular disc
depress and protrude mandible
attachments and action of the medial pterygoid
lateral pterygoid plate and maxilla -> angle of mandible (internally)
elevate and protrude mandible
3 divisions of trigeminal nerve
v1- opthalmic
v2 maxillary
v3 mandibular
function of V1 and V2
sensory innervation to face, oral/nasal/orbital cavityies
function of v3
motor innervation of muscles of mastication
