Deck 23: Extraoral Imaging

Question 1

Extraoral images may be used in conjunction with intraoral images.Extraoral images are not as defined or sharp as intraoral images.

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 1

Both statements are true.

Question 2

The lateral jaw projection

A)requires the use of a special x-ray unit.
B)provides for more diagnostic information than a panoramic image.
C)is used to examine the anterior portion of the mandible.
D)is valuable for patients with limited jaw opening because of a fracture or swelling.

Answer 2

is valuable for patients with limited jaw opening because of a fracture or swelling.

Question 3

A grid is composed of a series of

A)wire mesh that is similar to the screen in a window or door.
B)copper wires around an armature.
C)thin lead strips.
D)thick lead strips.

Answer 3

thin lead strips.

Question 4

The grid is placed between the ____________ and the ______________.

A)aluminum filter;PID
B)PID;patient's head
C)patient's head;film or PSP receptors
D)film or PSP receptors;cassette

Question 5

To compensate for the strips found in the grid,_______________ must be used to expose a film or PSP receptor.

A)increased kilovoltage
B)increased milliamperage
C)increased exposure time
D)decreased exposure time

Question 6

(1)Temporomandibular joint tomography is used to evaluate the condyle,articular eminence,and glenoid fossa.(2)Other landmarks are blurred in TMJ tomography.

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 7

For the transcranial projection,the central ray is directed toward a point _____ inches above and 0.5 inches behind the opening of the ear canal.

A)0.5
B)1.0
C)2.0
D)4.0

Question 8

A grid can be used to decrease scatter radiation,decrease film fog,and increase contrast on film and PSP receptors.A grid should only be used when it is necessary to improve image quality and increase contrast because it requires increased x-ray exposure.

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

An occlusal receptor (size ____)may be used for some extraoral images.

A)0
B)1
C)2
D)4

Question 10

An extraoral image is placed __________ the mouth during x-ray exposure.Extraoral imaging is used to image _________ areas of the skull or jaws.

A)outside;small
B)outside;large
C)inside;small
D)inside;large

Question 11

Which of the following is the fastest recommended screen and screen film combination?

A)Calcium tungstate screen with blue light
B)Calcium tungstate screen with green light
C)Rare earth screen with blue light
D)Rare earth screen with green light

Question 12

The front side of the cassette is typically constructed of ________ and permits the passage of the x-ray beam,whereas the back side is made of _________ to reduce scatter radiation.

A)metal;metal
B)plastic;plastic
C)plastic;metal
D)metal;plastic

Question 13

For which of the following projections would be you place the receptor parallel to the patient's cheek and have the patient tip her head 15 degrees toward the receptor with her chin slightly extended and elevated?

A)Lateral cephalometric projection
B)Ramus of the mandible projection
C)Reverse Towne projection
D)Waters projection

Question 14

Which of the following choices is a type of lateral jaw projection?

A)Lateral cephalometric projection
B)Reverse Towne projection
C)Waters projection
D)Body of the mandible projection

Question 15

Scatter radiation

A)increases film fog.
B)increases image contrast.
C)decreases film fog.
D)decreases density.

Question 16

Which of the following is the most commonly used extraoral film size?

A)3 × 5
B)4 × 6
C)5 × 7
D)8 × 10

Question 17

For the _____________ projection,the patient's face is against the receptor with both the forehead and chin touching the receptor.

A)posteroanterior
B)lateral cephalometric
C)reverse Towne
D)Waters

Question 18

(1)A thyroid collar is used for Waters,submentovertex,and reverse Towne projections.(2)A thyroid collar is not used for the lateral jaw,lateral cephalometic,and the posteroanterior projections.

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 19

An occlusal receptor ________ be used for some extraoral images.When used extraorally,it covers a ________ area than a screen film.

A)may;smaller
B)may not;smaller
C)may;larger
D)may not;larger

Question 20

Which of the following would you evaluate using an extraoral image?

A)Gutta percha placement in the root canal
B)Level of crestal bone
C)Recurrent decay
D)Growth and development

Question 21

In order to take this projection,you need to have your patient face the receptor,touch his forehead to the receptor,tuck his chin down to his chest,and open his mouth as wide as he can.Which projection is this?

A)Waters
B)Posteroanterior
C)Reverse Towne
D)Submentovertex

Question 22

The beam should be directed _______________ degrees for the ramus of the mandible projection.

A)downward at 15 to 20
B)upward at 15 to 20
C)downward at 45
D)upward at 45

Question 23

You have been asked to take a dental image to locate a fracture at the neck of the condyle.Which projection would you take?

A)Reverse Towne
B)Posteroanterior
C)Waters
D)Submentovertex

Question 24

The left side of the patient's head is positioned adjacent to the cassette for the _____________ projection.

A)lateral cephalometric
B)posteroanterior
C)Waters
D)submentovertex

Question 25

The purpose of the transcranial projection is to evaluate the articular eminence and _________ surface of the condyle.

A)anterior
B)posterior
C)superior
D)inferior

Question 26

Your patient thinks she has fractured her zygomatic arch.Which of the following projections would you take?

A)Lateral cephalometric
B)Posteroanterior
C)Waters
D)Submentovertex

Question 27

The patient's head and neck are tipped back as far as possible for the _____________ projection.

A)lateral cephalometric
B)posteroanterior
C)Waters
D)submentovertex