practice test Flashcards
how often should the lead apron and thyroid collar be disinfected
after every use
normal size adult patient film size for exposing a posterior periapical radiograph
2
how should the patients head be oriented when taking a pano
with the midsagittal plane perpendicular to the floor
how long should a DA wash hands for
15 sec min
DA technique to help with gagging
use a distraction
what can help protect patients from excess radiation dana he to tissues
high kVp
where is the expiration date on dental x-ray film printed
on the film packaging box
where should bitetabs placed on film for BW radiographs be positioned
white unprinted side of the packet
what landmark is useful when mounting films in the maxillary posterior area
floor of the maxillary sinus
how often should step wedge quality control tests for a dental x-ray machine be conducted ?
daily
equation used to determine the occupational maximum accumulated dose (MAD) of radiation
age - 18 x 5 rems/year
when does a panoramic image appear to have a “reverse smile”
when the frankfort plane is angled upward
what is contrast in a radiograph primarily controlled by
kVp
storing unexposed radiographic film in high humidity conditions may cause
film fog
for x-ray machines operating in ranges at or below 70 KVP the total aluminum equivalent filtration must be a minimum of
1.5 mm
the penetrating x-ray beam produced during dental radiography is called
primary radiation
what should the DA do before exposing a minor to radiographs
obtain consent from a parent or legal guardian
which radiograph technique is recommended for a patient with a shallow palate ?
bisecting
first step in processing radiographic film
developing
a film with damaged emulsion will appear
cracked
which landmark is useful when mounting films of the mandibular posterior area
mental foremen
when mounting periapical radiographs, what information helps to distinguish maximally molar radiographs from mandibular molar radiographs ?
the maxillary sinus sinus outline is visible
the amount of radiation and exposure time needed to produce a diagnostic radiographs is best determined by
film speed
a film with damaged emulsion will appear
cracked
intensifying screens is to
decrease the amount of the radiation exposure
when exposing radiographs the minimum distance the operator should stand from the tube head is
6 feet
an underexposed film will appear
light
what sequence best describes radiation injury to tissue
latent period, period of injury, period of recovery
radiation injury can be measured by
dose rate
what is a long term effect of radiation ?
genetic defects
phosphor plates are processed by using
laser beam technology
what increases density on duplicated film?
decrease the exposure time
what should x-ray machines be monitored for
radiation leakage
what cells exposed to radiation may be associated with leukemia?
somatic
according to the inverse square law, when changing PID length from 8 to 16 inches, the beam intensity is
1/4 as intense
light-colored radiographs result from
underexposure
when documenting a lesion going on a radiograph, what should all be documented?
size, appearance, & location
the maximum permissible dose (MPD) of ionizing radiation for occupational exposure is
5.0 rem per year
what condition may mimic caries on a intraoral radiograph
root resorption
when should gloves be placed on when giving an xray
after placing the led apron
what are CEPHALOMETRIC radiographs PRIMARILY used to evaluate
lateral jaw development
personnel monitoring for radiation exposure is done by
wearing a dosimeter
how frequently should processing solutions be replenished
daily
describe action of the developer solution
converts exposed silver halide crystals
the best way to correct a conecutting error is to adjust
film positions
compared to a dentulous (with teeth) patient, radiographic exposure time on an edentulous (teeth less) adult patient should
decrease
radiation that is formed by the interaction of the x-rays with matter is
secondary radiation
most bilateral findings in radiographs are considered
normal anatomic landmarks
what causes a dark image during film processing
overdeveloped film
what is first done to visually impaired patients
use touch to explain the equipment and procedure
processed films are handled by corners to prevent what
fingerprints
what lesion (damaged tissue) appears radiopaque on a radiograph ?
sclerotic bone
unusually hardness or thickness
what causes elongation on a radiograph?
insufficient vertical angulation
what film size is used for occlusal exposure?
4
don’t use what type of gloves to handle film in the daylight loader?
utility gloves
what extraoral radiograph is used to evaluate impacted teeth, large lesions & fractures of the mandible ?
lateral jaw projection
thyroid collar isn’t recommended for what type of radiographic exposure
panoramic
what measures the amount of radiation that reaches the surface of the skin?
roentgen
radiation that deflects off the patients head is called
scatter radiation
disposable intraoral x-ray film holder device
stabe
back-scatter radiation to the film is prevented by the
lead foil
when doing a pano on a edentulous patient, what would a DA use to stabilize the upper and lower arch on the bite block?
cotton rolls
to produce ionizing radiation, an atom must
add an electron
what helps decrease exposure of the thyroid gland from the primary radiation beam?
paralleling technique
most common radiograph exposure used to evaluate a dental IMPLANT
periapical
what influences the sharpness of a radiograph
focal spot size
what affects the speed of the electrons emitted from the tubehead?
kVp
which of the following affects the quantity of x-rays being emitted from the tubehead?
mA
double-ended film holder used for posterior and anterior teeth
eezee-grip
radiolucent landmarks useful when mounting films in the mandibular anterior area?
lingual foramen
diameter of the cone-shaped beam produced from a circular collimator is
2.5 inches
what do you adjust to produce wavelengths with the greatest penetrating power?
kVp
dilaceration in a radiographic image indicates the
root shape is abnormally bent or curved
most radiographic carious lesions appear
radiolucent (dark)
the annual maximum accumulated dose (MAD) of radiation for DA is based on what?
Age - 18 x 5rems/year
useful landmark when mounting films in the maxillary central areas?
anterior nasal spine
radiopaque vs radiolucent
light vs dark
after dismissal, clean counters with an EPA-registered
intermediate-level disinfectant
cone beam computer tomography uses
3D technology
cells most susceptible to radiation damage are
bone marrow
patients should wear a thyroid collar during which type of radiographic exposure
intraoral radiograph
the most radiolucent area on an anterior radiograph is the
nasal fossa
paralleling technique requires the film to be placed
away from the tooth, toward the middle of the oral cavity
on a full mouth series with eighteen films, how many anterior films are exposed?
6
the most common artificial radiation exposure comes from
medical radiation
maximum wattage for a safelight bulb should be
15
leakage radiation is defined as any radiation that is
from the primary beam
if there are no teeth to serve as guides, what landmarks indicates a maxillary molar area radiograph?
tuberosity
the population most susceptible to radiation damage is
infants
what prevents x-rays from escaping the tubehead?
leaded-glass housing
during radiographic exposures, semi-critical items that must be sterilized or disposed of include
film holding devices
when changing the 8-inch PID to a 16-inch PID, which of the following is used to determine the intensity of the beam
inverse square law
processing tanks should be cleaned when the
solutions are changed
compared to a round position-indicating device (PID), which of the following PIDs reduces patient radiation exposure up to 70%?
rectangular-shaped PID
most effective method of reducing patient exposure to x-radiation?
fast film
which radiolucencies may be mistakes for caries?
cervical burnout
the Buccal Object Rule is used to determine if a foreign body is located in which direction?
lingual to buccal
chemical agents should be properly disposed of according to
federal, state & local laws
added filtration in the x-ray tubehead protects the
patient
a radiograph will automatically be retaken when there is a
double exposure
on a radiograph, the anterior alveolar crest normally appears
pointed and sharp
purpose of aluminum disc in x-ray tube head
filter out long wave x-rays from the primary beam
ALARA is primarily concerned with radiation that is
artificial
remove film from protective packet, then
recycle lead foil in separate container
what causes white spots to appear on radiographs?
fixer solution contacts the film
what radiation effect increases in severity as more radiation is absorbed by somatic cells?
nonstochastic
according to CDC, how are the transmission of pathogens minimized when using phosphor sensors to capture radiographic images?
by placing a plastic barrier over the sensor
most common radiographic exposure used to detect periodontal disease is a
periapical
human tissue is mainly composted of
water
what part of x-ray machine should be covered or disinfected after each patient?
tubehead
impacted third molars are best seen with what type of radiograph
panoramic
when radiographs are mounted with the embossed dot appearing outward:
facial mounting
when lowering PID, exposure time must
increase
purpose of grid device on extraoral cassette
reduce scatter radiation reaching the film
What happens to a radiograph when fixer solution is low?
Straight black line/border appears
A pano with a dark shadow over the apices of the maxillary teeth may be caused by
Patient not placing tongue against the palate
What results in a double image radiograph?
Exposing the same film twice
Which film size is the longest?
3
What gloves are required for the decontamination of the darkroom?
Nitrile utility
one tooth is superimposed over the contact of another : means what?
overlapping
compared to the paralleling technique, a DISADVANTAGE of the bisecting angle technique is
image distortion
which of the following landmarks are located by the midline of the mandible
genial tubercles
the occlusal plane will appear diagonal in the radiograph when there is an:
incorrect film placement
when using an automatic processor, how many seconds should be allowed between the insertion of each dental film?
10
blurred radiographs are often caused by
patient movement during exposure
disadvantage of panoramic?
higher cost of equipment
One taking an occlusal radiograph, the film packet should extend from the patient’s mouth by approximately
1/8-1/4 inches
during the processing of an x-ray film, the removal of the halide portion of the exposed silver crystals is called?
reduction
the PID (position -indicating device) shape that most effectively reduces patient exposure to radiation is
rectangular
which PID produces the greatest amount of secondary radiation?
closed-end plastic cone
measurement of force that refers to the potential difference between two electrical charges?
voktage
what pathogen is not found in oral or respiratory secretions?
west nile virus
when a processed film has a straight clear border on the upper edge
developer solution too low
pregnant healthcare personnel can expose radiographs
their entire pregnancy
If a patient did not remove earrings prior to exposing a panoramic the radiograph could have
ghost images
The most important stuff the dentist can take to protect patients from x-radiation
properly prescribing radiographs
what quality control test evaluates safe lighting in the darkroom
coin test
how often should protective clothing be changed in an oral healthcare setting
when visibly soiled
what film size is most effective for evaluating caries and periodontal heath when placed vertically in the anterior region of the mouth?
2
measurement of tissue damage from x-ray energy?
radiation absorbed dose
foreshortening of the maximally radiographic image results from
increased vertical angulation
the American Dental Association recommends that radiographs be mounted with the embossed dots
all facing the same direction
the most common reason for taking bitewing
to evaluate interproximal caries
The optimum developing solution temperature for manual processing is
68 ° f
The Best radiograph to evaluate a suspected salivary stone in the submandibular gland is an
occlusal
most important responsibility of the DA in dental radiography is
implementing ALARA principle
the edentulous radiographic series may include all of the following EXCEPT
bitewings
radiation injury results from
exposure
developing solution temperatures should be checked frequently when using
manual processing
what organization regulates disinfectants and chemical sterilants
EPA
the purpose of fixer solution
to remove unexposed silver halide crystals
the radiation exposure that poses the greatest hazard to the operator is
leakage radiation
A full mouth series of periapical radiographs taken on an endentulous patient will consist of
6 anterior & 8 posterior
primary function of collimation is to
restrict the size of the beam
The optimal temperature of the developer in automatic processing is
80-95° f
What radiation injury theory describes cells that are damaged by way of absorption
indirect
the median palatal suture is visible on what radiograph?
maxillary anterior periapical
to help desensitize the tissue prior to film placement the DA should
rub a finger along the tissues where the film touches
when transporting a disposable cup containing patients exposed film to the development area the DA should
carry the container UNGLOVED
The most commonly used radiographic exposure for a three-year-old patient is
bitewing
if the DA’s dosimeter badge report indicated exposure to radiation, what’s done first?
evaluate the x-ray equipment and technique
What best describes what happens when two films contact each other during processing?
overlapped films
supernumerary teeth are best detected using which film type?
panoramic
Who regulates the manufacturing and installation of x-ray equipment?
Federal government
which film would be exposed to see the relationship of the Alveolar bone
vertical bite wing
The best way to prevent cross-contamination from an exposed film packet is by?
using individual barrier envelopes
dental x-rays should be prescribed when the
benefits outweigh the risk of harm
after removing an exposed film from a patient’s mouth the next step is to
dry the exposed film
what is the primary advantage in using digital radiography?
reduces the radiation to patient
somatic effects of radiation do NOT have damaging effects on
offspring
what error occurs when the vertical angulation is incorrect?
elongation
what can be observed on a panoramic radiograph when the patient’s chin is tipped downwards?
exaggerated smile
to maintain quality assurance while processing films the DA should record
the date solutions were changed
film should be stored in
the original lead-wrapped packaging
to view an abscess on tooth #25, the best radiographic exposure is a
periapical
Radiographs appear dark after processing when the developing solution is
too warm
The normalizing device can be used to monitor
developer strength
what condition will result in a radiographic image that is too light?
weak developing solution
The primary purpose of a bite wing radiograph is to evaluate
Interproximal Decay
the Frankfort Plane is an imaginary plane passing through the
external auditory meatus to the floor of the orbit
One taking radiographs on a small child who cannot hold the firm intra-orally the DA should
ask a parent or guardian to hold the film
when preparing to take a digital radiograph, after selecting the appropriate sensor size for the patient, the next step is to
place a barrier on the sensor
The time between patient exposure to radiation and the appearance of biological damage is the
latent period
what causes the interproximal areas of the teeth to appear overlapped?
improper horizontal angulation
what film size would be used for an adult periapical film?
2
emulsion damage to a film is caused by
improper handling of film
patient receive less radiation when using a _____ PID
rectangular
where is the most common area in the oral cavity for a dentigerous cyst?
around the 3rd molar
