Chapter 11 Notes - Cranium, Facial Bones, and Sinuses Flashcards
1
Q
what bone is rests on the superior end of the vertebral column?
A
skull
2
Q
what are the 2 main sets of bone of the skull?
A
- 8 cranial bones
- 14 facial bones
3
Q
what are the cranial bones broken up to?
A
calvarium (skullcap) and floor
4
Q
what are the bones in the skullcap?
A
- frontal
- right parietal
- left parietal
- occipital
5
Q
what are the bones in the floor?
A
- right temporal
- left temporal
- sphenoid
- ethmoid
6
Q
what is the frontal bone?
A
the bone that makes up the forehead and the superior part of each orbit
7
Q
what are the 2 main parts of the frontal bone?
A
forehead - squamous/vertical portion
superior orbit - orbital/horizontal portion
8
Q
define glabella
A
smooth/raised prominence between the eyebrows just above the bridge of the nose
9
Q
define supraorbital groove (SOG)
A
slight depression above each eyebrow
10
Q
define supraorbital margin (SOM)
A
superior rim of each orbit
11
Q
define supraorbital notch
A
- foramen
- small hole or opening, slightly medial to the SOM
- supraorbital nerves and arteries pass through
12
Q
define frontal tuberosity
A
- eminence
- large/rounded prominence superior to the SOG
13
Q
what 4 bones does the frontal bone articulate with?
A
- right/left parietal
- sphenoid
- ethmoid
14
Q
what bone forms the lateral walls of the cranium and part of the roof?
A
two parietal bones
15
Q
define parietal tubercles (eminence)
A
widest portion of the entire skull
16
Q
what 5 bones does the parietal bone articulate with?
A
- frontal
- occipital
- temporal
- sphenoid
- opposite parietal bones
17
Q
define occipital bone
A
inferoposterior portion of the calvarium/skullcap
18
Q
define squamous portion
A
- round
- forms most of the back of the head
- superior to the external occipital protuberance/inion
19
Q
define the foramen magnum
A
- large opening at the base of the occipital bone
- spinal cord passes as it leaves the brain
- “great hole”
20
Q
what condyles of the skull articulate with C1 atlas?
A
condylar portions/occipital condyles
21
Q
what type of joint is formed between the occipital condyles and C1?
A
atlantooccipital joint
22
Q
what 6 bones does the occipital bones articulate with?
A
- 2 parietals
- 2 temporals
- sphenoid
- C1/atlas
23
Q
define temporal bones?
A
- left and right
- protect the delicate organs of hearing and balance
24
Q
what are the three primary parts that break down the temporal bone?
A
- squamous portion
- mastoid portion
- petrous portion/petrous pyramid/pars petrosa
25
which part of the skull is the most vulnerable to fractures?
squamous portion
26
define petrous portion
houses the organs of hearing and equilibrium, including mastoid air cells
27
what portion of the temporal bone is the thickest and densest bone in the cranium?
petrous portion
28
define internal acoustic meatus
opening or orifice that transmit the nerves of hearing and equilibrium
29
what 3 bones does the temporal bone articulate with?
- parietal
- occipital
- sphenoid
30
what bone is centrally located in the skull and anchors the other seven cranial bones?
sphenoid bone
31
define sella turcica
- central depression of the body
- surrounds/protects the pituitary gland
32
define superior orbital fissures
openings providing additional communication with the orbits for numerous cranial nerves and blood vessels
33
what examinations can be done to visualize a deformity int he sella turcica?
CT and MRI
34
what are the 8 cranial bones?
- frontal
- right parietal
- left parietal
- occipital
- right temporal
- left temporal
- sphenoid
- eithmoid
35
define cribriform plate
portion of the bone containing several small openings/foramina where segmental branches of the olfactory nerves pass
36
where is the ethmoid located?
beneath the floor of the cranium
37
what bones does the ethmoid bone articulate with?
- frontal
- sphenoid
- 11 facial bones
38
define vomer
midline structure between parts of the sphenoid and parts of the ethmoid
39
define sutures
articulations/joints of the cranium
40
what is the classification of the stures?
fibrous joints
40
what type of mobility are the sutures of an adult cranium?
- synarthrodial-type joints
- immovable
41
list the 4 sutures in the cranium
- coronal suture
- sagittal suture
- lambdoidal suture
- squamous suture
42
define bregma
anterior end of the sagittal suture
43
define lambda
posterior end of the sagittal suture
44
define pterions
points at the junction of the frontal, parietals, temporals, and greater wings of the sphenoid
45
define asterions
points posterior to the ear where the squamosal and lambdoidal sutures meet
46
define fontanels
- space between the bones of the skull in an infant/fetus, where ossification is not complete
- sutures are not fully formed
47
define anterior/posterior fontanels
- bregma and lambda in infants
- "soft spots"
-
48
which fontanel is the largest at birth?
anterior fontanel
49
when does the anterior fontanel close during infancy?
18 months
50
what are the 6 fontanels in an infant?
- anterior fontanel
- posterior fontanel
- right sphenoid fontanel
- left sphenoid fontanel
- right mastoid fontanel
- left mastoid fontanel
51
define sutural/wormian
small/irregular bones
52
what structure is found in the petrous portion and temporal bone?
organs of hearing and equillibrium
53
what are the 3 divisions of the ear?
- external
- middle
- internal
54
what structures belong to the external ear?
- auricle
- pinna
- tragus
55
define (EAM) External acoustic meatus
opening or canal of the external ear
56
define middle ear
irregular shaped, air containing cavity
57
what structures make up the middle ear?
- tympanic membrane
- auditory ossicles
- tympanic cavity
58
define eustachian tube
passageway between the middle ear and the nasopharynx
59
what is the function of the eustachian tube?
serves to equalize the pressure within the middle ear to the outside atmospheric air pressure through the nasopharynx
60
what structures make up the internal ear?
internal acoustic meatus
61
what is a second direct communication in the middle ear?
mastoid air cells
62
what connects to the mastoid air cells?
antrum
63
what is the function of the auditory ossicles?
- permit vibratory motion
- transmit sound vibrations from the tympanic membrane to the oval window of the internal ear
64
what are the three auditory ossicles?
- malleus
- incus
- stapes
65
which out of the 3 auditory ossicles is the smallest bone?
stapes
66
what membrane leads to the inner ear?
oval window
67
how does sense of hearing occur?
when the longer root of the incus connects to the stapes, which connects to the oval window of the cochlea
68
what are the 3 parts of the osseous/bony labyrinth
- cochlea
- vestibule
- semicircle canals
69
what is the function of the semicircular canals?
sense of direction or equilibrium
70
what is the function of the cochlea?
sense of hearing
71
what are the 2 membranes of the internal ear?
- oval window/vestibule
- round window/cochlea
72
define oval window/vestibule
receives vibrations from the external ear (stapes), transmitting them to the vestibule
73
define round window/cochlear
membrane that allows the movement of fluid within the closed duct system
74
how does sense of hearing occur?
Vibrations and associated slight fluid movements within the cochlea produce impulses that are transmitted to the auditory nerve within the internal acoustic meatus
75
which 2 facial bones are unpaired?
vomer and mandible
76
which is the largest immovable facial bone?
(2) maxilla
77
what are the structures of the maxilla?
- body
- 4 processes
78
what are the 4 processes in the maxilla?
- palatine process
- frontal process
- zygomatic process
- alveolar process
79
define hard/bony palate
anterior portion of the roof of the mouth
80
define the zygoma
form the prominence of the cheeks and makeup the lower portion of the orbits
81
which bone is fractured due to a blow in the cheek?
zygomatic arch
82
which bones are the thinnest and most fragile?
lacrimal and nasal bones
83
define lacrimal bone
small/delicate bones that lie very close to the tear ducts
84
define nasal bone
- form the bridge of the nose
- the rest of the nose is made up of cartilage
85
define nasal conchae
- made up of three pairs
- divide nasal cavities into various compartments
- break up/mix the flow of the air before it reaches the lungs
86
what is the largest facial bone?
mandible
87
which bone is the only movable bone in the adult skeleton?
mandible
88
what classification is the temporomandibular joint?
synovial/diarthrodial
89
what is the movement type for the temporomandibular joint?
- bicondylar
- plane/gliding
90
what is the classification for alveoli and roots of teeth?
- fibrous/synarthrodial
- immovable
91
what is the subclass of the alveoli and roots of teeth?
gomphosis
92
define paranasal sinuses
- large, air filled cavities
- lined with mucous membranes
93
