Cranium, Facial Bones, Zygomatic Arches And Orbits Flashcards
Smallest bones in the skull
Lacrimal bones
What passes through the lacrimal foramen
Tear duct
Nasal bones articulate with eachother in what plane
Mid sag
Which facial bones have pairs
Nasal, lacrimal, maxillary, zygomatic, palatine, inferior nasal conchae
Largest immovable bones of the face
Maxillary
Where are lacrimal bones found
Anterior part of the medial wall of the orbits between the labyrinth of the ethmoid bone and the maxilla
What X-rays show the lacrimal bones
Pa and lateral projections
Where are lacrimal bones found
Anterior pard of the medial wall of the orbits between the labyrinth of the ethmoid bone and The maxilla
The alveolar process
Thick spongy ridge on the inferior border of maxilla
Each maxilla contains a large
Pyramidal cavity called maxillary sinus
Maxillary bones form a pointed forward -projecting process called
Anterior nasal spine
Zygomatic bones form the
Prominence of the cheeks and part of the side wall and floor of orbital cavities
Nasal conchae are
Long, narrow, extremely thin, curl laterally
Small u-shaped bone situated at the base of the tongue
Hyoid bone
Sutures are classified by
Fibrous joints of the suture type
The atlantooccipital joint is a
Synovial ellipsoidal joint
Bones of the orbit
Frontal, sphenoid, ethmoid, maxilla, zygoma, lacrimal and palatine
The long axis of the orbit is oblique and forms an angle of what with midsag
37 degrees
The superior orbital fissure is the cleft between
The greater and lesser wing of the sphenoid bone
Blowout fracture is best seen on what X-ray
Pacietoacanthial projection - waters method
Fracture of orbital floor
Blowout fracture
Fractures of zygomatic arch
Depressed fracture
Tripod fracture - all three sutures
Maxilla fracture
Lefort fracture ( I, II, III)
Facial bone fracture is a
Visceral cranial fracture
Slowest healing bone in the body
Mandible
What projection do you do for a blowout fracture
Modified waters
Most frequently fractured facial bone
Nasal bone
Lefort I
Palate
Blowout fracture is a
Orbital floor fracture
Lefort II
Nose and palate
Lefort III
Entire face
Lefort I : nasomaxillary signs
Malocclusion, buccal ecchymosis, epistaxis, maxillary creptius and maxilla mobile
Lefort II: pyramidal - signs
Midface crepitus, facial lengthening, bilateral epistaxis,infra orbital parasthesia, ecchymosis
Lefort III: craniofacial disjunction signs
Caved in or flattened, lengthened face, csf rhinoronea, bilateral epistaxis
2 bones that form the bony nasal septum
Perpendicular plate of ethmoid bone and vomer
Cones of the eyes form an angle of what with msp
37 degrees
Cones of the eye form an angle of what with IOML
30 degrees
When the orbits are of interest for a Pa Caldwell what is the angle
30 degree caudal angle
How many facial bones are there
14
the nasal bones form the
bony wall of the nose
nasal bones articulate with
frontal, ethmoid, and maxillae
how many pairs of nasal conchae
3
which bones form the nasal conchae
ethmoid form superior and middle concha and facial bones form inferior concha
where are the lacrimal bones located
medial wall of each orbit
the maxilla bone articulates with all other facial bones except for the
mandible
the maxilla bone forms part of the
lateral walls and most of the floor of the nasal cavity
what is located under each orbit and serves as a passage through which the infraorbital nerve and artery reach the nose
infraorbital foramen
inferior borders of spongy bone that support roots of teeth
alveolar process
zygomatic bones form the
cheekbones, part of the side wall and floor or orbits
what extends posteriorly to join the zygomatic process of the temporal bone
temporal process
palatine bones are composed of
2 L shaped bones composed of vertical and horizontal plates
which two bones form the hard palate
maxilla and palatine
vomer is situated in
MST of the floor of the nasal cavity
the vomer forms the
inferior nasal septum
the hyoid bone is an
accessory bone
where is the hyoid bone situated
the base of the tongue
sutures are what type of joint
fibrous immovable
how many bones if the orbit formed by
7
function of orbits
protect eyes
how are blowout fractures usually imaged
CT
tripod fracture
fracture of the zygomatic arch
slowest healing bone in the body
mandible
lefort fracture
maxilla fracture
lefort I fracture
horizontal fracture of the maxilla
Lefort II fracture
a pyramid-shaped fracture involving inferior orbital rim
lefort III fracture
involved seperation of all the facial bones from their cranial base
most severe lefort fracture
Lefort III
what plane is lined up for lateral facial bones
IOML parallel
why would a 30 degree caudal angle be used for a PA axial caldwell method for facial bones and what is it called
to show orbital rims
exaggerated caldwell
patient head position for tangential zygomatic arches
top of head resting on the board, rotate MSP of head 15 degrees toward side being examined
3 point landing for rhese method
nose, cheek and chin
what angle does MSP form with the IR for these method
53 degree angle
when the CR is perpendicular where are petrous ridges
fill the orbit
when the CR has a 15 degree caudal angle where are petrous ridges
lower thirds of orbits
when CR has 30 caudal angle where are the petrous ridges
below the orbits
3 bones that form the orbital rim
frontal, maxilla and zygoma
which bone forms three fourths of the roof of the mouth
maxillary bone
typical skull
mesocephalic
skull that is short front to back, broad side to side and shallow vertex to the base
brachycephalic
Skull that is long front to back, narrow side to side, and deep vertex to base
dolichocephalic
the petrous pyramids form an average angle of _____ degrees in dolichocephalic
40
the petrous pyramids lie at an average angle of ___ degrees in the brachycephalic
54
petrous pyramids project anteriorly and medially at an angle of ___ from the MSP in a mesocephalic skull
47
cone-shaped, bony-walled cavities situated on each side of the MSP of the head
orbits
each orbit has a
roof, medial wall, lateral wall, and a floor
the apex of the orbit corresponds to the
optic foramen
cleft between the greater and lesser wings of the sphenoid bones
superior orbital fissure
narrow cleft extending from the lower anterolateral aspect of the sphenoid body anteriorly and laterally between the floor and lateral wall of orbit
inferior orbital fissure
what parts of the orbits are very fragile
floor and walls
Rods are used for
Night vision and fluoro viewing
cones are used for
day light and to see color
rods or cones cant see color
rods
rods or cones have high spatial acuity
cones
for high spatial resolution do you need large or small focal spot
small