WorksheetsRHS Exam Practice
Total questions: 60
Worksheet time: 33mins
Exposure to radiation:Exposure to radiation:
no matter how small, has the potential to cause harmful biologic changes.
has a threshold, below which exposure is entirely safe
is safer when there is a single, large dose rather than a series of smaller doses
from a dental x-ray machine does not involve particulate radiation and is completely safe.
The x-ray was discovered on November 8, 1895, by:
John Greenwood.
Wilhelm Conrad Roentgen.
V. Black
Edmund Kells
The dentist who is credited with the first practical use of radiographs in dentistry in 1896 is:
Wilhelm Conrad Roentgen.
V. Black
Edmund Kells.
John Greenwood.
Anything that occupies space and has a form or shape is:
energy
solid
matter
photon
Which of the following statements is true concerning the structure of the atom?
The nucleus contains protons and electrons.
Electrons have no weight or mass.
The orbital path of an electron around the nucleus is called an electron shell.
Electrons are unstable in their orbits and shift freely.
dentistry, the _____ the wavelengths of the x-rays, the greater their energy and their usefulness.
shorter
longer
more ionized
straighter
Which component of the x-ray machine functions in positioning the tubehead?
Kilovoltage selector
control panel
extension arm
cathode
Secondary radiation:
a. is often referred to as the useful beam.
b. is often referred to as the primary beam.
refers to x-radiation that is created when the primary beam interacts with matter.
is a form of radiation that occurs when an x-ray beam has been deflected from its path by
interaction with matter.
Which of the following structures will appear radiopaque on dental x-ray film?
Metal restorations
Soft tissue
Tooth decay
Dental pulp
The term _____ is used to describe areas that appear dark on the image; _____ is the term used to describe areas that appear white or light gray.
a. radiopaque; radiolucent
b. radiolucent; radiopaque
ANS: B REF: p. 595 TOPIC:
Feedback
c. density; contrast d. contrast; density
radiopaque; radiolucent
radiolucent; radiopaque
Density; contrast
contrast; density
The range of shades of gray between black and white on an image is called:
Contrast
Density
Sharpness
Focus point
The degree of density or blackness on an image is controlled by the:
Low voltage circuits
Kilovltage
Milliampere seconds
Positions indicating device
_____ will improve the sharpness of a radiographic image.
A large facial spot size
Faster film
Smaller film crystal size
Movement of the patient
Damage caused by ionizing x-radiation to genetic cells:
a. affects only the person being x-rayed.
b. can affect future generations.
c. affects only the dental assistant.
d. affects the cells of the eye, skin, and oral mucosa.
Which of the following tissues has the highest radiation sensitivity?
Small lymphocytes
Salivary gland
Kidney
Muscle tissue
A lead apron and a thyroid collar:
are utilized for a full mouth series of films but are not necessary for single periapical films.
must be used on all patients for all exposures.
are required for pediatric patients but is optional for adults.
are mandated only for pregnant women.
The Guidelines for Prescribing Dental Radiographs issued by the American Dental Association and the FDA recommend which of the following dental imaging procedures for a pregnant patient?
Do not take images on a pregnant patient.
Radiographic imaging procedures do not need to be altered because of pregnancy.
Take images only after the first trimester.
One of the rules of radiation protection is to never stand closer than _____ feet from the x-ray unit during an exposure unless you are behind a barrier.
4
6
9
15
Dental imaging:
detects conditions that might otherwise remain undetected.
refers to digitally produced images
refers to film-based images.
All the above
Which is not true of electromagnetic radiation?
They are made up of photons that travel through space in waveforms.
They travel at various speeds.
They differ only by their wavelength.
They travel in straight lines.
A(n) _____ is a minute bundle of energy that has no weight or mass.
Ion
atom
photon
electrons
The _______is the portion of the x-ray machine which supplies the electrons to produce x-rays?
Cathode
Anode
control panel
focusing cup
If you change the exposure time of the x-ray unit, what is affected?
Energy of the beam
wavelength of the X-ray
number of X-rays produced
penetrability of the X-ray
The _____ setting controls the penetrating power of the x-ray beam.
Impulse timer
kilovolt setting
Milliamp setting
all the above
Thermionic emission refers to the:
release of electrons from the tungsten filament.
ions formed in the x-ray tube by the loss of electrons.
change in filament resistance due to heating.
slamming of electrons against the target.
The lead collimator is used to ______ of the primary beam.
make the primary beam more accurate
restrict the size and shape
remove long wavelengths
sTOPIC production
Primary radiation is
Also called the useful beam
the beam of X-ray that comes from the target
less penetrating than secondary radiation
both a and b
The time lapse from x-ray exposure until noticeable damage occurs is known as
The latente period
chronic exposure
the cumulative period
none of the above
Chronic radiation exposure occurs when _____ doses of radiation is received over a ____ time period.
Large; short
large; long
small; short
small; long
Damage to which type of cell is passed on to future generations?
Somatic cell
genetic cell
Damage to either somatic cells or genetic cells is passed on to future generations
Damage to neither somatic cells nor genetic cells is passed on to future generations
Which of the following organs are not more sensitive to x-rays and therefore not considered critical organs?
Skin
muscle
thyroid gland
lens of the eye
The dentist says that the image has too much contrast; he would like to see more grays. What adjustment would you make?
Increase mA
increase kVp
decrease kVp
decrease mA
When in storage, the lead apron should be
Hung
folded
draped over a bar
both a & c
The location where x rays are produced in the x ray tube is called the
Focal spot
filament
window
PID
When the exposed button is engaged, what happens
The high voltage circuit is activated
kilovolts drive the electrons to the target
electrons slam against the target producing the X-ray
all the above will happen
An exposure time of 1/2 second is equal to____ impulses
1/2
2
30
12
The most commonly used film size for adults intramural dentistry is size
#0
#4
#3
#2
Which of the following is an extra oral film that is placed outside the mouth during X-ray exposure
Occlusal
panoramic
pedia-iCal
bite wing
_____ is a device that intensifies or increases the effect of the radiation and decreases the amount of exposure time needed when exposing an extraoral radiograph.
Screen film
film cassette
Intensifying screen
Non screen films
____ hardens the film emulate during film processing…
Rinsing
developing
fixing
washing
Automatic films processing requires ___ tha manual films processing
More time
less equipment
more space
more equipment
Which of the following time and temperature errors will result in reticulation of the film
Inadequate development time
developers solutions too hot
sudden temperature change between developer and water bath
inaccurate timer or temonmeter
Film Speed id determined by the
thickness of silver bromide salt
thinkness of cellulose acetate base
size of the silver bromide crystals
both a and b
the purpose of the lead doil in the dental film packet is to
provide stiffness to the films
reduce film fogging
absord the primary beam
make the packet more flexible and resilient
when placing a dental film in the patient's mouth, the white side is placed the tube and the raised dot to the
toward; apical
toward; occlusal or incisal
away; apical
away; occlusal or incisal
which is not true of duplicating films emulsion
it is only on oen side
it appears shiny
it appears dull
it is exposed by light
the _- is the safest place to store unopened boxes of dental film
darkroom
furance room
refrigerator
treatment room
which is the correct order of steps in manual film processing
fix, rinse, develop. wash
develop, rinse, fix, wash
fix, wash, rinse, wash
rinse, develop, fix, wash
the film is ligter than normal; what us the probable casue
the developer solution is too weak
the developer solution is too warm
the fixer soultion is too weak
the film was not properly rinsed
in the automatic processor, the developing solution is normally 81 F to 83 F. If it gets hotter, how will the films look
dark/black
gray
clear
Light
the ideal time and temperature for manual developing is
45 seconds at 85 F
5 min at 65C
5 min at 68 F
5 min at 60 F
what is the cause of white spots on a processed film
static electricity
solutions are too warm
fixer contacts film prior to processing
drops of developer
digital radiography requires less radiation than traditional radiography because the
exposure time is increased
sensor is smaller
senor is more sensitive to xray energy
senor is attached to the computer
which of the following statement is true regarding federal and state regulationson the use of dental x ray equipment
all dental x ray machines manufactured or sold in the US after 1934 mus meet federal regulations
the use of dental x ray equipment is regulated by federal but not state regulations
the federal government requires x ray machines to be registed and charges a fee for this registration
most states have laws that require inspections of dental x ray equipment on a regular basis
the porcess of informing the patient about the nature anbd purpose of dental imaging is termed
informed consent
disclosure
respondeat superior
quality control test
dental images are the proerty of the
dentist
patient
insurance company
quility assurance is away of ensuring that everything possible is being doen to produce high quality diagnostic images and includes quality
adminstration porcedures
control tests
control of deantal staff credentials
both a and b
teh safelight in the darkroom can be tested by
using the coin test
turning off all the lights in the darkroom
using a step wedge
taking a reference image
inorder for films to be properly processed, it should beleft in a fixer solution, at full strength, for how long
30 min
1 min
2 min
5 min
who is responsible for overall quaily assurance in a dental practice
dentist
dental assistant
dental hygienist
