radiology and radiography

Question 1

What produces a radiograph image?

Answer 1

X-rays passing through an object and interacting with the photographic emulsion on a film

Question 2

What do X-rays affect if a digital image is being formed?

Answer 2

A sensory or phosphor plate

Question 3

When were radiographs first used?

Answer 3

1896

Question 4

What are intra-oral X-ray types?

Answer 4

Bitewing (horizontal and vertical)
Periapical
Occlusal (maxilla and mandible)

Question 5

What are extra oral X-ray types?

Answer 5

DPT
lateral cephalogram
Posters-anterior mandible
Lateral oblique mandible
Occipito-mental views of facial bones

Question 6

In the atom, what does the nucleus contain?

Answer 6

Protons
neutrons

Question 7

What orbits an atoms nucleus in energy shells?

Answer 7

Electrons

Question 8

What is atomic mass number?

Answer 8

Proton number + neutron number

Question 9

What are atoms with the same proton number but different neutron number?

Answer 9

Isotope

Question 10

What are isotopes with unstable nuclei which undergo radioactive disintegration?

Answer 10

Radioisotope

Question 11

What is an ion?

Answer 11

A charged atom or molecule

Question 12

What is an anion?

Answer 12

Negative charge when there are more electrons

Question 13

What is a cation?

Answer 13

Positive charge if there are more protons

Question 14

What are the 3 radioactive emissions?

Answer 14

Alpha particles
Beta particles
Gamma rays

Question 15

What makes alpha particles?

Answer 15

2 protons
2 neutrons

Question 16

What makes beta particles?

Answer 16

Electrons

Question 17

What makes gamma rays?

Answer 17

Electromagnetic radiation

Question 18

Order radioactive emissions by size

Answer 18

Alpha - large
Beta - small
Gamma - Nil

Question 19

Order radioactive emissions by charge

Answer 19

Alpha - positive
Beta - negative
Gamma - nil

Question 20

Order radioactive emissions by speed

Answer 20

Alpha - slow
Beta - fast
Gamma - very fast

Question 21

Order radioactive emissions by penetration

Answer 21

Alpha - 1-2mm in tissue
Beta - 1-2cm in tissue
Gamma - pass through tissue

Question 22

Order radioactive emissions by energy

Answer 22

Alpha - 4-8MeV
Beta - 100keV- 6MeV
Gamma - 1.24KeV - 12.4MeV

Question 23

Order radioactive emissions by damage potential

Answer 23

Alpha - extensive ionisation
Beta - ionisation
Gamma - ionisation

Question 24

What type of emission are dental X-rays?

Answer 24

DO NOT occur naturally and don’t involve radioactive decay
Identical to gamma rays - with lower energy values

Question 25

What are the properties of dental X-rays ?

Answer 25

No weight No charge Very fast Cause ionisation

Question 26

What is X-ray generation ?

Answer 26

Converting one energy form (electricity) to another

Question 27

What X-rays show the crown to the apices of the root and clearly in between the teeth?

Answer 27

Periapicals

Question 28

What X-rays show the distal edge of the 4 to the mesial edge of the 8?

Answer 28

Bitewing

Question 29

What X-rays show bone but not entire root of tooth?

Answer 29

Vertical Bitewing

Question 30

What does a maxillary occlusal radiograph show?

Answer 30

Upper maxilla and anterior teeth

Question 31

What does a lower mandibular occlusal radiograph show?

Answer 31

Tooth bearing portion of mandible and floor of mouth

Question 32

How are DPT radiographs formed?

Answer 32

X-ray tube rotates around the patients head with a constant long exposure of 14 seconds

Question 33

What can make positioning of DPTs difficult?

Answer 33

Body shape

Question 34

What radiographs are used in orthodontics to assess the relationships of teeth to jaws and mandible to the rest of the facial skeleton?

Answer 34

Lateral Cephalogram

Question 35

What part of lateral cephalograms make them useful for surgical planning?

Answer 35

Soft tissue pattern of the nose and lips

Question 36

What radiographs are useful for showing a fracture of the mandible?

Answer 36

Postero-anterior mandible

Question 37

What radiographs are used for children that can’t tolerate a Bitewing?

Answer 37

Lateral oblique mandible

Question 38

What radiographs are the most common in first instance when a patient reports with a facial trauma?

Answer 38

Occipito-mental views of facial bones

Question 39

What do occipito-mental views of facial bones show?

Answer 39

Fractures of orbits, maxilla and zygomatic arches

Question 40

Why is it beneficial to take occipito- mental views erect?

Answer 40

Help demonstrate fluid levels in the antra

Question 41

What causes the difference between extra and intra oral radiographs?

Answer 41

The object distance from the receptor

Question 42

What are the clinical indications for periapical radiography?

Answer 42

Detection of apical infection Evaluation of apical cysts/ other lesions in bone Assessment of periodontal status Post trauma Assessment of root morphology prior to extractions Assessment of eruption Endodontics Post and pre apical surgery Implant evaluating

Question 43

What is a bisected angle?

Answer 43

Patient holds film

Question 44

What is the standard technique of choose when taking intraoral radiographs?

Answer 44

Paralleling

Question 45

What are disadvantages of holders?

Answer 45

Bulky - may not be tolerated by patient

Question 46

What are holders made up of?

Answer 46

Bite block Indicator arm/ rod Aiming ring

Question 47

What are the colours of holders and what are they used for?

Answer 47

Blue - anterior Yellow - posterior Red - Bitewings Green - endo

Question 48

What part of the holder is the image taken on?

Answer 48

Receptor

Question 49

What are receptors?

Answer 49

Phosphor plates

Question 50

What should the vertical plane be parallel to?

Answer 50

Long axis of the tooth

Question 51

What must the horizontal plane of the film be parallel to?

Answer 51

Dental arch

Question 52

What position must the X-ray beam be in?

Answer 52

Right angle to the tooth and receptor

Question 53

What is the rectangular attachment at the end of the X-ray tube?

Answer 53

Collimator