Special tests - radiographs

Question 1

what are radiographs

Answer 1

Images created using X-ray photons

Question 2

how does a radiograph work?

Answer 2

X-ray photons pass through an object before interacting with a receptor

Question 3

what are the 3 ways that x-rays interact with matter?

Answer 3

transmitted - passes through unaltered

absorbed - stopped by the tissue

scattered - changed direction

Question 4

what two x-ray interactions contribute to the attenuation of x-ray photons

Answer 4

absorbed and scattered

Question 5

what does the radiographic image represent

Answer 5

the pattern of attenuation of the x-ray photons after they pass through the matter

Question 6

what does the term radiolucent mean?

Answer 6

darker areas on the image, less attenuation of x rays ( x - rays pass more easily)

Question 7

what does the term radiopaque mean

Answer 7

lighter areas on the image, more attenuation of X-rays

Question 8

what is a key thing to remember about radiographic terminology?

Answer 8

they are relative not absolute terms.

Question 9

why do we use radiographs

Answer 9

to show anatomy and pathology that is not visible to the naked eye

Question 10

what is a common use of radiographs in dentistry

Answer 10

assess caries in the mouth

Question 11

how would a dental cary appear on a radiograph

Answer 11

results in decreased radio density therefore will appear radiolucent compared to the rest of the tooth

Question 12

name the three categories of common radiographs in dentistry

Answer 12

intra-oral
extra-oral
cross-sectional

Question 13

name the 3 intra-oral radiographs (different angles)

Answer 13

bitewing
periapical
occlusal

Question 14

name the 2 extra-oral radiographs

Answer 14

panoramic
lateral cephalogram

Question 15

name the cross- sectional radiograph

Answer 15

cone beam computed tomograph

Question 16

what does a bitewing radiograph show?

Answer 16

provides a view of multiple side teeth (premolars and molars)

• crowns
• part of the roots
• some interdental bone

Question 17

what is a common radiograph to take to identify caries?

Answer 17

bitewing (pre-molars and molars)
(easy to assess anterior teeth vs posterior teeth for caries therefore don’t need to x-ray anterior teeth)

Question 18

what does a periapical radiograph show

Answer 18

full length view of a particular tooth/teeth

• crown and entire root
• entire height of bone support around tooth

Question 19

what does a panoramic radiograph show

Answer 19

provides a “zoomed out” view of both mandible and maxilla.

can be “full” or “sectional”

Question 20

what does occlusal radiography show

Answer 20

provides a view of one dental arch

either maxillary or mandibular

can be taken at different angles (anterior or lateral) (true or oblique)

Question 21

what is an advantage of occlusal radiography

Answer 21

allow teeth to be seen from different view points

Question 22

what does cone beam computed tomography show

Answer 22

provides cross-sectional imaging of teeth/jaws “3D scan”

Question 23

when would cone beam computed tomography

Answer 23

only used when routine dental imaging cannot provide the require information

Question 24

why is cone beam computed tomography not commonly used

Answer 24

• increases radiation dose, decreases resolution and increases cost

Question 25

how should radiographs be arranged for viewing

Answer 25

position radiographs as if you were facing the patient

Question 26

how would you identify mandible and maxillary teeth from a bitewing radiograph

Answer 26

maxillary tooth would show 3 roots.

Question 27

what is the curve of spee

Answer 27

Normal anatomical curvature of the occlusal plane

curves upwards posteriorly

Question 28

what are non dental anatomy to help identify maxillary teeth

Answer 28

maxillary sinus
nasal cavity
maxillary tuberosity

Question 29

what are non dental anatomy to help identify mandibular teeth

Answer 29

interior alveolar canal
mental foramen
inferior border of mandible
external oblique ridge

Mental foramen lies below premolars