Advertisement Upgrade to remove ads

The tube head limits the size of the primary beam by regulating the:

a. Size of the tube
b. Number of electrons
c. Length of the cylinder
d. Diameter of the collimator
e. Thickness of the filter

D

The collimator restricts the size of the beam.

Increasing the film-to-source distance results in:

a. Less distortion
b. More distortion
c. Elongation
d. Foreshortening

A

Film-to-source or source-to-film distance is determined by the length of the cone. The longer the cone, the less distortion.

The purpose of the lead diaphragm in the tube head is to:

a. Filter out low level x-ray
b. Diffuse the x-ray beam
c. Limit size of x-ray beam
d. Prevent scattered radiation

C

The collimator which restricts the size of the beam is made of lead in the shape of a diaphragm (disk with a hole in it).

Dental film speed is determined by the amount of exposure needed to:

a. Penetrate the lead foil in the film packet
b. Block the path of the central beam
c. Reduce contrast on the radiography
d. Produce a diagnostic radiograph

D

The spread of the film determines how much x-ray is needed to expose the film

When placing the dental film packet, the white side of the film:

a. Is placed facing the tooth
b. Is placed towards the tongue
c. Has no bearing on placement
d. Is placed away from x-rays

A

The white side is also called the tube side because it faces the source of x-rays

The speed film requiring the least amount of x-ray exposure is:

a. A
b. B
c. C
d. D
e. E

E

E speed fil requires about 1/2 the exposer as D speed.

Vertical angulation in radiographic projections regulates the:

a. Contrast of the image
b. Width of image
c. Definition of the image
d. Length of image
e. Overlapping of image

D

The less vertical angle, the longer the image more vertical angle results in a SHORTER image.

Horizontal angulation in radiographic projections regulates the:

a. Length of image
b. Contrast of the image
c. Overlapping of image
d. Definition of image

C

Incorrect horizontal angle results in overlapping.

The maximum permissible dose (MDP) for the operator is:

a. 4 R per year
b. 5 R per year
c. 6 R per year
d. 7 R per year

B

Maximum permissible is 5 R or 5 rems per year (.05 Sv)

3 R or 3 rems per Quarter (.03 Sv)
.1 rem per week (.001 Sv)

Public / Pregnant radiation workers are 1/10 of the above:

.005 / year
.003 / quarter
.0001 / week

The most radio-sensitive facial tissue is:

a. Cheek
b. Eye
c. Lip
d. Nostril

B

Lens of the eye to be specific.

X-radiation that has passed through an object is termed:

a. Emission
b. Primary radiation
c. Secondary radiation
d. Absorption

C

Secondary or scatter radiation. It has a longer wavelength and has less penetrating power.

Activating the electronic timer causes the x-ray tube to:

a. Emit electrons
b. Deactivate the electron cloud
c. Emit secondary radiation
d. Emit primary radiation

D

Activating the timer causes x-ray production (primary beam)

The body tissue most sensitive to x-ray damage is:

a. Bone
b. Blood
c. Muscle
d. Skin

B

Specifically leucocytes

The effect of x-radiation on human tissue is:

a. Momentary
b. Temporary
c. Cumulative
d. Negligible

C

Cumulative - meaning damage is never completely healed. It continues with each x-ray exposure.

Adjusting milliamperage of the x-ray tube:

a. Quantity of x-rays
b. Quality of x-rays
c. Contrast of the radiograph
d. Wavelength of the x-rays

A

mA controls the amount of x-radiation

The type of x-rays best able to penetrate body tissues are:

a. Soft rays of long wavelength
b. Soft rays of short wavelength
c. Hard rays of long wavelength
d. Hard rays of short wavelength

D

Hard or penetrating x-rays are those of SHORT WAVELENGTH.

The negatively charged part of the x-ray tube is the:

a. Cathode
b. Anode
c. Target
d. Focal spot

A

Cathode contains the filament for the source of electrons and is negative.

To provide a single radiograph of the patient's complete dentition, the exposure of choice is the:

a. Bitewing
b. Occlusal
c. Periapical
d. Panoramic

D

Panoramic radiograph gives the a view of the full dentition.

Which film size is considered for children only:

a. 3
b. 2
c. 1
d. 0

D

0 size film is so small, the only application that it has is children.

The optimal time for rinsing films between developing and fixing during manual processing is:

a. 10 min
b. 30 sec
c. 20 min
d. 10 sec

B

Developing is timed according to the temperature, fixing is always 10 minutes, by rinsing between the two is 30 seconds. The final wash is 20 minutes in running water.

The function of the x-ray fixing batch is to:

a. Stop the developing action
b. Darken exposed silver salts
c. Give contrast to the film
d. Remove traces of chemicals

A

Stopping development is one function. The other functions are to remove undeveloped silver halides and shrink/harden the emulsion.

The chief source of radiation exposure to the operator is:

a. Primary radiation
b. Scattered radiation
c. Hard radiation
d. Image forming radiation

B

Scattered or secondary radiation.

Light and x-radiation travel at what speed?

a. 86,000 miles per second
b. 186,000 miles per second
c. 1,186,000 miles per second
d. 2,186,000 miles per second

B

When a film holder device is not being used, what is the recommended position for the sagittal plane of the patient?

a. 135 degrees to the floor
b. Parallel to the floor
c. Perpendicular to the floor
d. 45 degrees to the floor

C

The sagittal plane divides the patient into right and left. To keep the patient's head upright, it must be perpendicular to the floor.

What will be the result of placing the film backwards in the mouth?

a. Herringbone pattern
b. Partial image
c. Film fog
d. Extreme density

A

the x-rays traveled through the lead foil first, leaving the lead foil pattern on the film.

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again

Example:

Reload the page to try again!

Reload

Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording

Create Set