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Flashcards in rad 2 Deck (44):
1

what does PID stand for

position Indicating Device

2

what does XCP stand for

Extension cone paralleling

3

what does OFD stand for

object to film distance

4

what does TFD stand for

Target film distance

5

What does SID stand for

source image distance

6

what does AFD stand for

anode film distance

7

what does FFD stand

focal film distance

8

which acronyms are synonymous

TFD, SID, AFD, and FFD
TFD is most common though

9

what are rules for paralleling technique

Sensor placement, sensor position, Vertical angulation, horizontal angulation, and sensor exposure

10

T/F: the sensor should be placed parallel to long axis of tooth

true

11

T/F: the central ray of the X-ray beam is directed parallel to the sensor

false; the central ray should be perpendicular to the sensor ------ray----- lsensorl

12

what should be used to keep the film holder parallel with the long axis of the tooth

a sensor/film holder

13

what size sensor is used in the anterior region of adults

size 1

14

which size sensor is used in the posterior of adults and adolescence in a horizontal direcrtions

size 2

15

how can you ensure that only the most parallel rays will be directed at the tooth

increase the target-sensor(or film) distance

16

cone placement in an up and down direction

Vertical angulation

17

cone placement in a side to side direction

horizontal angulation

18

what is horizontal angulation especially important for

bitewing, keeping contacts open

19

what is the correct order of steps:
1. film/sensor placement
2. equipment preparation
3. exposure sequence for film/ sensor placements
4.patient preparation

4, 2, 3, 1

20

how should you prep the patient

-explain the procedure
-adjust chair
-adjust headrest
-place and secure the lead apron *
-remove all objects from mouth (i.e. lip or tongue ring)

21

how should you prep the equipment

-set exposure factors
-prepare sensor
-open sterilized package contains beam alignment device

22

should you start with anterior or posteriors first

anteriors

23

defined as the specific area where the film/sensor must be positioned before exposure; what is this dictated by?

film placement; teeth and surrounding structures (i.e. tori)

24

what can be used for paralleling technique when the pt has a shallow palate

cotton rolls: 2, one on each side of bite block
vertical angulation: can be increased by 5-15 degrees

25

how do you compensate for a pt who has a maxillary torus

sensor must be placed on far side of torus and then exposed

26

how do you compensate for a pt who has a mandibular tori

the sensor must be placed b/w the tori and tongue then exposed

27

advantages of paralleling technique

-accuracy: image is distortion-free
-simplicity: eliminates need to determine horizontal and vertical angulation
-duplication: comparison of serial radiographs has great validity

28

Disadvantages of paralleling

film placement may be difficult
discomfort

29

in this technique, the sensor is placed in the mouth parallel to the crowns of both upper and lower teeth

bite wing technique

30

error: film appears clear, image will not register on computer

unexposed film/sensor

31

failure to turn on machine, electrical failure, or malfunction of the x-ray machine will result in

un unexposed film/sensor

32

Error: film appears black

film/sensor exposed to light

33

Error: film/image appears dark

overexposed film

34

excessive exposure time , kilovoltage or mill amperage set to high will cause

overexposed film/sensor

35

Error: film/image appears to light

underexposed film

36

the film/sensor being underexposed or setting to low will cause

underexposed film

37

What causes the film to appear distorted

incorrect vertical angulation

38

what causes images to appear foreshortened(short teeth with blunted apices)

excessive vertical angulation; too steep

39

what causes images to appear elongated

vertical angulation is too flat

40

overlap is caused by what

central ray was not directed through the interproximal spaces

41

an image that appears tilted is caused by what

dropped film/image corner

42

the PID not properly aligned with the film/sensor holder will cause

cone cut

43

Error: a thin radiolucent line appears over film

creasing

44

what causes creasing?

film being creased; exclusive to film