Deck 22: Panoramic Imaging

Question 1

Advantages of panoramic receptors over intraoral periapical receptors include visualization of
1)impacted third molar teeth.
2)jaw fractures.
3)large lesions in the posterior mandible.

A)1,2,3
B)1,2
C)1,3
D)2,3

Answer 1

1,2,3

Question 2

The collimator used in panoramic imaging has an opening in the shape of a _____________ slit.

A)narrow horizontal
B)narrow vertical
C)wide horizontal
D)wide vertical

Answer 2

narrow vertical

Question 3

The panoramic image is the preferred image for the detection of caries and periodontal disease.The panoramic image is preferred for the evaluation of eruption patterns,growth,and development.

A)Both statements are true.
B)Both statements are false.
C)The first statement is true;the second statement is false.
D)The first statement is false;the second statement is true.

Answer 3

The first statement is false;the second statement is true.

Question 4

In panoramic imaging,the ___________ is a theoretical concept used to determine where the dental arches must be positioned to achieve the clearest image.

A)waypoint
B)focal trough
C)neutral zone
D)home zone

Question 5

Which component in the panoramic x-ray machine tubehead is most different from that found in an intraoral x-ray machine tubehead?

A)Filament
B)Target
C)Heat sink
D)Collimator

Question 6

The tubehead of the panoramic unit always rotates _________ the patient's head as the receptor rotates _________ the patient.

A)behind;behind
B)in front of;in front of
C)behind;in front of
D)in front of;behind

Question 7

A panoramic image is __________ image(s)taken using __________ technique.

A)a series of;intraoral
B)a series of;extraoral
C)a single;intraoral
D)a single;extraoral

Question 8

All panoramic units have the same focal trough size and shape.Panoramic units may have different receptor transport mechanisms.

A)Both statements are true.
B)Both statements are false.
C)The first statement is true;the second statement is false.
D)The first statement is false;the second statement is true.

Question 9

The rotational change in a panoramic machine allows the image layer to conform to the ___________ shape of the dental arches.

A)square
B)tapering
C)ovoid
D)elliptical

Question 10

In panoramic imaging,the x-ray tube rotates around the patient's head in one direction while the receptor rotates __________________ direction.

A)horizontally in the same
B)horizontally in the opposite
C)vertically in the same
D)vertically in the opposite

Question 11

In panoramic imaging,the movement of the receptor and the tubehead produces an image through the process known as

A)scanography.
B)digitizing.
C)scintillation.
D)tomography.

Question 12

The closer the rotation center is to the teeth,the narrower the focal trough.In most panoramic machines,the focal trough is wide in the anterior region and narrow in the posterior region.

A)Both statements are true.
B)Both statements are false.
C)The first statement is true;the second statement is false.
D)The first statement is false;the second statement is true.

Question 13

The function of the collimator used in the panoramic x-ray machine is to ____________________.

A)align the patient's teeth as accurately as possible in the focal trough.
B)generate the x-rays.
C)restrict the size and shape of the x-ray beam.
D)prevent a ghost image.

Question 14

Green-sensitive film must be paired with intensifying screens that produce ________ light.

A)yellow
B)blue
C)red
D)green

Question 15

Panoramic screen film is exposed by

A)photons.
B)electrons.
C)intensifying screens in a cassette holder.
D)a shutter in the cassette with visible light.

Question 16

You are examining your patient's panoramic image.You notice that the molars and premolars on the right side are larger than the teeth on the left side.What patient positioning error did you make?

A)The patient's head was turned to the right.
B)The patient's head was turned to the left.
C)The patient is slumped.
D)The patient's teeth are behind the focal trough.

Question 17

In panoramic imaging,the pivotal point,or axis,around which the cassette carrier and x-ray tubehead rotate is termed a

A)terminal hinge axis.
B)rotation center.
C)tipping point.
D)germinal center.

Question 18

Structures are clearly demonstrated on a panoramic image in a _____________ zone.

A)two-dimensional straight
B)two-dimensional curved
C)three-dimensional straight
D)three-dimensional curved

Question 19

An anatomic structure that is located outside of the focal plane and close to the x-ray source can cast a ghost image on the panoramic image.The ramus of the mandible is one example of a structure that can cast a ghost image on the panoramic image.

A)Both statements are true.
B)Both statements are false.
C)The first statement is true;the second statement is false.
D)The first statement is false;the second statement is true.

Question 20

The vertical angulation in the tubehead of the panoramic unit

A)is fixed in position so that the x-ray beam is directed slightly upward.
B)is fixed in position so that the x-ray beam is directed slightly downward.
C)can be adjusted according to the size of the patient.
D)can be adjusted for maxillary or mandibular imagings.

Question 21

Rare earth screens emit _______ light and are considered faster than calcium tungstate screens,which emit _______ light.

A)blue;green
B)blue;blue
C)green;green
D)green;blue

Question 22

A "reverse smile line" is seen on the image if the patient's

A)chin is tipped down.
B)chin is tipped up.
C)teeth are positioned too far back on the bite-block.
D)teeth are positioned too far forward on the bite-block.

Question 23

The anterior teeth will appear "skinny" if the

A)chin is tipped down.
B)chin is tipped up.
C)teeth are positioned too far back on the bite-block.
D)teeth are positioned too far forward on the bite-block.

Question 24

Which of the following should appear in a panoramic image that was taken correctly?

A)The posterior teeth on the right side appear larger than the posterior teeth on the left side.
B)The anterior teeth are narrow.
C)The hard palate appears on the apical portion of the maxillary teeth.
D)The pulp chambers are clear and visible in the anterior teeth.

Question 25

You should have your 75-year-old patient remove her partial dentures and her hearing aids before taking a panoramic image because ghost images occur that could cover diagnostic information on the panoramic image.

A)Both parts of the statement are true.
B)Both parts of the statement are false.
C)The first part of the statement is true;the second part of the statement is false.
D)The first part of the statement is false;the second part of the statement is true.

Question 26

A cassette has ________ intensifying screen(s).

A)one
B)two
C)three
D)four

Question 27

A ghost image appears ___________ than/of its actual counterpart.

A)on the same side
B)higher
C)more distinct
D)smaller

Question 28

Your digital panoramic image appears dark and has burned-out areas.Which of the following would you need to adjust in order to have a diagnostic image?

A)Computer software
B)Time
C)Focal trough
D)Patient positioning

Question 29

The panoramic image of your patient has two radiopaque areas,one on each side,in the bottom portion of the image.What do you need to do to correct the error?

A)Remove the lead apron.
B)Use a lead apron without a thyroid collar.
C)Have the patient remove her partial denture.
D)Have the patient stand up straight.

Question 30

If the patient's lips are not closed on the bite-block during the exposure of a panoramic image,a _____________ shadow results that obscures the anterior teeth.

A)light radiopaque
B)dark radiopaque
C)light radiolucent
D)dark radiolucent

Question 31

The exposure settings (milliamperage,kilovoltage,and time)are all adjustable on the panoramic machines.Adjustments of milliamperage and kilovoltage are made to change between panoramic and extraoral bite-wing exposures and time is used to accommodate different patient sizes.

A)Both statements are true.
B)Both statements are false.
C)The first statement is true;the second statement is false.
D)The first statement is false;the second statement is true.

Question 32

An "exaggerated smile line" is seen on the dental image if the patient's

A)chin is tipped down.
B)chin is tipped up.
C)teeth are positioned too far back on the bite-block.
D)teeth are positioned too far forward on the bite-block.

Question 33

A disadvantage of panoramic dental imaging when contrasted with intraoral dental imaging is

A)panoramic imaging results in higher exposure to the patient than intraoral imaging.
B)fewer anatomic structures can be viewed on a panoramic image than on a complete intraoral imaging series.
C)the images seen on a panoramic image are not as sharp as those on intraoral images because of the intensifying screens.
D)the exposure of a panoramic image is readily accepted by the patient because there is no discomfort involved.

Question 34

The anterior teeth will appear "fat" if the

A)chin is tipped down.
B)chin is tipped up.
C)teeth are positioned too far back on the bite-block.
D)teeth are positioned too far forward on the bite-block.