Skull Radiographic Views And Anatomy

Question 1

Name radiographs from lowest to highest dose of radiation

Answer 1

OPT
full mouth periapicals
CBCT
Cone beam of full mouth

Question 2

what are skull radiographs

Answer 2

plain radiographs used primarily for assessing maxillofacial trauma

Question 3

what are the four main types of skull radiographs

Answer 3

occipitomental
posterio-anterior mandible
Reverse Towne’s
true lateral skull

Question 4

what are occipitomental radiographs primarily used for

Answer 4

fractures of the midface

Question 5

what are postero-anterior mandible radiographs primarily used for

Answer 5

fractures of the posterior mandibles (but not including condyles)

Question 6

what are Reverse towne’s radiographs primarily used for

Answer 6

fractures of mandibular condyles

Question 7

how are occipitomental radiographs usually taken

Answer 7

at two different angles
eg between 0, 10, 30 or 40 degrees and choosing two values not close to one another

Question 8

what is Water’s view

Answer 8

using two different angles to take an occipitomental radiograph

Question 9

how is the patient positioned for an occipitomental radiograph

Answer 9

face receptor
head tipped back so orbitomeatal line is 45 degrees to receptor
x-ray beam positioned at the degree which the operator has chosen and centred through the occiput

Question 10

why are PA mandible radiographs not suitable for viewing facial skeleton

Answer 10

due to superimposition of base of skull and nasal bones

Question 11

what are indications for a PA mandible radiograph

Answer 11

lesions and fractures involving the posterior third of body of mandible, angles, rami
mandibular hypo or hyperplasia

Question 12

how is the patient positioned for a PA mandible radiograph

Answer 12

face towards receptor
head tipped forward so orbitomeatal line is perpendicular with receptor (forehead nose position)
x-ray beam perpendicular to receptor and centred through cervical spine at level of rami

Question 13

why is the x-ray beam projected from posterior side in PA mandible, occipitomental and Reverse Townes radiographs

Answer 13

reduced magnification of the face since the face is closer to receptor

reduced effective dose

Question 14

what are indications for taking a Reverse Towne’s radiograph

Answer 14

high fractures of condylar necks
intracapsular fractures of TMJ
condylar hypo or hyperplasia

Question 15

how is the patient positioned for a Reverse Towne’s radiograph

Answer 15

face towards receptor
head tipped forward so orbitomeatal line perpendicular with the receptor
mouth open so condylar heads move out of glenoid fossa
x-ray beam 30 degrees below perpendicular line to receptor and centred through condyles