Exam III

Question 1

Unit of effective dose:

Answer 1

REM

Question 2

High electron generating then stops:

Answer 2

tungsten target

Question 3

Cells more resistant to radiation will:

Answer 3

low capacity of reproduction; more differentiation

Question 4

Increase in cone length will:

Answer 4

increased sharpness, higher density

Question 5

What image is between X-RAY SOURCE and ROTATION CENTER:

Answer 5

Ghost image

Question 6

Does not cause ionization:

Answer 6

coherent radiation

Question 7

Object moves distal, source moves distal:

Answer 7

lingnual

Question 8

What is the tissue modification factor?

Answer 8

Effective dose

Question 9

Factors affecting caries presentation:

Answer 9

angle of X-ray beam & degree of cavitation

Question 10

What is an intraoral radiograph sign of present or past periodontal disease?

Answer 10

alveolar bone loss at furcation of molar

Question 11

No threshold=

Answer 11

cancer

Question 12

What is in the cathode?

Answer 12

filament & focusing cup

Question 13

Mesial of #30:

Answer 13

within physiological limits

Question 14

The narrowest portion of the focal trough is in:

Answer 14

incisal area

Question 15

Central plane of image layer:

Answer 15

focal trough

Question 16

Predisposition to perio disease:

Answer 16

tilted/rotated

Question 17

What is the distortion if the teeth are located outside of the central place TOWARDS the ROTATION CENTER:

Answer 17

stretched wide in a horizontal direction

Question 18

what affects caries diagnosis?

Answer 18

both vertical & horizontal angulation

Question 19

A short object to receptor distance will decrease unsharpness; smaller focal spot increases unsharpness

Answer 19

First true; second false

Question 20

Hard palate is superimposed on maxillary roots:

Answer 20

chin up

Question 21

Increasing KeV does ______ energy of photon and ____ penetration

Answer 21

increases; higher penetration

Question 22

What film size do you use for occlusal radiographs?

Answer 22

PSPP and conventional

Question 23

What ford DICOM stand for?

Answer 23

digital imagine and communications in medicine

Question 24

What is the focusing cup made of?

Answer 24

molybdenum

Question 25

What does the LOW voltage power supply heat?

Answer 25

filament

Question 26

Who discovered the first intraoral radiograph?

Answer 26

Otto walkhoff

Question 27

Is produced when electrons interact with atoms of the target:

Answer 27

Bremsstrahlung Radiation

Question 28

Why is tungsten used as the target material:

Answer 28

high radiation coefficient

Question 29

What does a rectifier do?

Answer 29

changes the voltage for the AC current

Question 30

If the X-ray tube is set at 60 kVp, then the maximum voltage is:

Answer 30

60 kEv

Question 31

What skull radiograph is used to identify growth and development:

Answer 31

lateral cephalometric

Question 32

MPD measures threshold for:

Answer 32

ionizing radiation

Question 33

What skull radiograph sis used to evaluate facial asymmetries?

Answer 33

Posteroanterior cephalometric

Question 34

Where do you place the beam for a lateral maxillary occlusal projection?

Answer 34

Just below lateral canthus of the eye

Question 35

What does increases source-to-object distance do?

Answer 35

decreases magnification

Question 36

When do you take radiographs on a pregnant women?

Answer 36

only in emergent situation

Question 37

What is the best radiograph for interporximal caries diagnosis?

Answer 37

Horizontal bitewing with open contacts

Question 38

What skull radiograph is used to identify the maxillary sinuses?

Answer 38

Waters

Question 39

How does some thing that is anterior to the focal trough appear?

Answer 39

narrower

Question 40

Inverse square law, if the distance is tripled intensity:

Answer 40

decreases by 9

Question 41

Something in the focal trough will appear:

Answer 41

reasonably well-defined

Question 42

Compared to CCD, CMOS is:

Answer 42

faster to digitize

Question 43

What receptor has the LEAST radiation dose?

Answer 43

CCD

Question 44

What is located between the SOURCE and CENTER OF ROTATION?

Answer 44

Ghost image

Question 45

What is true about panos?

Answer 45

multiple centers of rotation

Question 46

What is high contrast?

Answer 46

short grey scale

Question 47

What is true regarding panos?

Answer 47

unequal magnification

Question 48

if you decrease voltage form 70 to 60 kVp, then you:

Answer 48

decrease density, increase contrast

Question 49

What is the 2012 ADA recommendation for an adult new patient at a high caries risk?

Answer 49

bitewings every 12-18 months

Question 50

When are electrons decelerated to produce X-rays?

Answer 50

when hitting the tungsten target

Question 51

Thermionic emission does what?

Answer 51

heats up and emits electrons

Question 52

Which of the following interactions causes biologic effects?

Answer 52

Compton scattering

Question 53

Low contrast means:

Answer 53

more shades of gray