Facial Bone and Orbits Lecture
For a SMV Projection of the Zygomatic bones, what positioning line is parallel to the IR?
IOML
For a lateral Facial Bone projection what positioning line will be parallel to the IR?
IOML
For a lateral Nasal bones, what positioning line will be parallel to the IR?
IOML
For a lateral orbits, what positioning line is parallel to the IR?
IOML
For a lateral Facial Bone projection what positioning line will be perpendicular to the IR?
IPL
For a lateral Nasal bone, what positioning line will be perpendicular to the IR?
IPL
For a lateral Orbits, what positioning line is perpendicular to the IR?
IPL
For an Axiolateral of the TMJ, what positioning line is perpendicular to the IR?
IPL
For a Parietoacanthial (waters) for facial bones, what positioning line with be perpendicular to the IR?
MML
What facial bones have aleovar processes?
Maxiallae and mandible
For a AP Axial Modified Towne Zygomatic Bones, what positioning is perpendicular to the IR?
OML
For a PA Mandibular rami, what positioning line is perpendicular to the IR?
OML
For an AP axial TMJ's what is the positioning line that is perpendicular to the IR?
OML
What projection is usually employed to show medial or lateral displacement of fragments in fractures of the rami?
PA axial projection
What is the CR for Parietoacanthial (waters) for facial bones?
Perpendicular to exit acanthion
What structure is of primary interest when the patient's head is rotated 15 degrees toward the IR from a true lateral position and the central ray is directed 15 degrees caudad, entering about 1 1/2 inches superior to the upside EAM?
TMJ
What projection is useful for patients with depressed fractures or flat cheekbones?
Tangential Projection of the zygomatic arches
Through what positioning landmark of the face should the central ray exit for a PA mandibular rami?
acanthion
To what landmark of the head should the IR be centered for a Parietoacanthial facial bones, Water method?
acanthion
To what positioning landmark should the central ray be directed for a Acanthioparietal facial bone, reverse waters method?
acanthion
What projection is performed with the patient's head positioned true lateral and the central ray directed 25 degrees cephalad?
axiolateral projection of the mandible
Where should the petrous ridges be seen in the image of the parietoacanthial projection of the facial bones?
below the maxillary sinuses
What term refers to the posterior process of the mandibular ramus?
condyle
What term refers to the anterior process of the mandibular ramus?
coronoid
To demonstrate the mandibular rami with the PA projection, what two facial structures should be touching the vertical grid device?
forehead and nose
What two facial structures should be touching the vertical grid device for a PA axial mandibular rami?
forehead and nose
How should the MSP be positioning with reference to the IR for a Axiolateral Oblique TMJ?
form an angle of 15 degrees
To demonstrate the manidibular body with the axiolateral oblique projection, how should the patient's head be positioned?
from true lateral, rotate the head 30 degrees toward the IR
What is the central ray for a Parietoacantial Modified Water for the Orbits?
horizontal and perpendicular to MSP exiting orbits
How does the vertebral column affect the image for a PA mandibular rami?
it superimposes the central part of the mandibular body
where are the lacrimal bones located?
medial wall of each orbit
What projection shows a blow out fracture?
modified waters method/modified parietoacanthial
What bones compose the bridge of the nose?
nasal
To what facial landmark should the unmasked portion of the IR be centered for a lateral nasal bone?
nasion
Where is the vomer bone found?
on the floor of the nasal cavity
What bones form the posterior one fourth of the roof of the mouth?
palatine
For a SMV projection of the Zygomatic arches, what is the CR?
perpendicular to IOML entering MSP at level 1 inch posterior to outer canthi
What is the CR for a lateral nasal bone?
perpendicular to entering 1/2 inch distal to nasion
What is the central ray for a PA Mandibular Rami?
perpendicular to exit the acanthion
What is the CR for a Lateral Facial bone projection?
perpendicular to lateral surface of zygomatic bone 1/2 in between outer cants and EAM
What is the central ray for a PA mandibular body?
perpendicular to level of lips
What is the central ray for a lateral orbits?
perpendicular to outer canthus
with what bone does the mandible articulate?
temporal
For the SMV projection , what causes the zygomatic arches to be projected beyond the parietal eminences?
the divergent x-ray beam
What part of the patient should be in contact with the grid device for a SMV zygomatic arches?
vertex of the skull
The temporal process projects posteriorly from what facial bone?
zygomatic
What facial bone should be centered to the IR for a Lateral facial bone?
zygomatic
what bone comprises most of the lateral wall of the orbital cavities?
zygomatic
With reference to the patient, where should the central ray be directed for the lateral projection of the facial bones?
zygomatic bone
How much rotation of the patients head is needed to demonstrate the mandibular rami?
0 degrees or true lateral
With reference to the patient, where should the IR be centered for axiolateral oblique projection of the TMJs?
1/2 inch anterior the EAM closest to IR
How many degrees and in what direction should the central ray be directed for the axiolateral oblique projection for TMJs?
15 degrees caudad
What is the central ray for an Axiolateral Oblique of the TMJ?
15 degrees caudad entering 1 1/2 inches superior to upside EAM and exiting TMJ closest to IR
With reference to the IR, how should the MSP be adjusted for the tangential projection demonstrating an individual zygomatic arch?
15 degrees from perpendicular
What is the central ray for a PA Axial Mandibular Rami?
20 to 25 degrees cephalic to exit acanthion
How many degrees and in what direction should the central ray be directed for the Axiolateral projection of the mandible?
25 degrees
What is the central ray for an Axiolateral of the TMJ?
25-30 degrees caudad entering 1/2 inches anterior and 2 inches superior to upside EAM exiting downside TMJ
For the AP axial projection of the TMJs, where should the central ray be directed?
3 inches above the nasion
Where should the central ray enter the patient for an AP axial TMJ?
3 inches above the nasion
An AP axial projection (modified Towne method) of the bilateral zygomatic arches is produces an image similar to the AP Axial Projection (town method) of the skull. How many degrees and in what direction should the central ray be directed for this projection to demonstrate zygomatic arches when the OML is perpendicular to the IR?
30 degrees
What is the CR for a AP Axial Modified Towne of the Zygomatic Bone?
30 degrees caudad to enter labella 1 inch above nasion
How much rotation of the patients head is needed to demonstrate the body of the mandible?
30 degrees toward IR
How many degrees and in what direction should the central ray be directed for an AP Axial TMJ?
35 degrees caudad
What is the central ray for an AP axial TMJ's?
35 degrees caudad entering 3 inches above nasion passing though TMJ's
For a Parietoacanthial (waters) for facial bones, the OML forms how much of an angle?
37 degrees
How much rotation of the patients head is needed to demonstrate the symphysis of the mandible?
45 degrees toward the IR
For a Parietoacanthial Modified Waters for the Orbits, how much of an angle is formed from the OML to the IR?
50 degrees
For a PA Mandibular Body, what positioning line is perpendicular to the IR?
AML
For an Axiolateral Oblique of the TMJ, what positioning line will be parallel to the IR?
AML
