blue tinted polyester acetate
What is the base of dental film composed of?
gelatin and silver halide crystals
What is the emulsion composed of?
size of crystals, thickness of emulsion, radiosensitive dyes
What determines the speed of dental films?
absorb scatter radiation and prevent fogging
What is the purpose of the lead foil?
faster film = lower definition and detail
How does film speed correlate with definition and detail?
D, E, F
What speed films are most commonly used?
#0
size film used for PA’s on small children
#3
size film used for BW on adults when only one film is taken on each side
#1
size film used for anterior PA’s for patients with narrow arches
#2
size film used for PA’s on adults
#2
size film used for BW on adults
#4
size film used for occlusals on adults
to distinguish b/w patient’s right and left side
What is the purpose of the embossed dot
invisible image (remains like this until film is processed)
What is the latent image
reduces the exposed silver halide crystals to black metallic silver
What happens in the developer
removes the unexposed silver halide crystals
What happens in the fixer
5 min
how long does film stay in the developer
10 min (dbl the development time)
how long are films fixed
20 seconds
how long does the first rinse last
20 min
how long is the final rinse
68 degrees F
what is the optimum processing temp.
after 2-3 min of fixing if needed
when can the films be exposed to white light
-old or contaminated processing solutions
-exposure to chemical fumes
-faulty safelight
-scatter radiation
-exposure to chemical fumes
-faulty safelight
-scatter radiation
what causes film fogging
-underexposure
-underdevelopment
-depleted developer solution
-excessive fixation (takes all crystals off)
-underdevelopment
-depleted developer solution
-excessive fixation (takes all crystals off)
what would cause a film to be too light
-overexposure
-overdevelopment
-developer is too strong
-not enough fixation
-exposure to white light
-improper safelighting
-overdevelopment
-developer is too strong
-not enough fixation
-exposure to white light
-improper safelighting
what would cause a film to be too dark
film placed backwards
What causes a HERRINGBONE effect
blank or clear
(takes all of the crystals off)
(takes all of the crystals off)
what would happen to a film that is placed in the fixer prior to development
cracking of the emulsion caused by excessive temp diff. b/w any darkroom solutions
what is reticulation
top of film delineated by a straight line then dark
how would a film appear if submerged totally in the developer but not in the fixer
part that was fixed but not developed would be clear
film submerged totally in fixer but not in developer
7 1/2 or 15 watt
what size bulb is used in safelight
GBX – 2
what type of safelight filter is acceptable
4 feet
how far from the work surface must the safelight be mounted
direct – directly obtaining a digital image by exposing intraoral sensor to x-rays to provide an image that can be viewed on a computer
indirect – photostimuable phosphor plate sensor technology, obtaining a digital image in which an exposed phosphor plate is placed into a scanner and then converted into a digital image
diff. b/w direct and indirect exposure sensor?
BW
what film is used to diagnose interproximal decay
left molar PA
what projection would you take for a patient complaining of pain in the lower left molar area
image the entire dentition, surrounding alveolar bone, sinuses, and the TMJ, examine large area of face and jaws, locate impacted teeth, retain root tips, evaluate trauma, lesions, and diseases, and assess growth and development
what is the purpose of a pano
excessive vertical angulation
what causes foreshortening
insufficient vertical angulation
what causes elongation
incorrect horrizontal angulation
what causes overlapping
not centered on sensor
what causes conecut
no exposure, or fixer before developer
what causes clear film
excessive vertical angulation
what causes missing crowns
insufficient vertical angulation
what causes missing apices
left side
when mounting a film the dot is convex, on what side of the mouth would you find #32?
– max molars have 3 roots, mand have 2 roots
how do you differentiate b/w max and mand molar when mounting
No. 0
what size film is 7/8 x 1 3/8
No. 1
what size film is 15/16 x 1 9/16
No. 2
what size film is 1 1/4 x 1 5/8
No. 3
what size film is 1 1/16 x 2 1/8
No. 4
what size film is 2 1/4 x 3
-Photostimuable Phosphor Plate aka storage phosphor system
-indirect digital imaging
-captures analog data then processed in a laser scanning device
-light is then converted into electrical signal that the computer uses to create the digital image
-indirect digital imaging
-captures analog data then processed in a laser scanning device
-light is then converted into electrical signal that the computer uses to create the digital image
Explain PSP
cut exposure time by 1/3
how does exposure time differ b/w adults and children
vertical BW
what type of projection is used to visualize the crestol alveolar bone on a patient with moderate to severe bone loss
-nasal septum, ant. nasal spine, nasal fossa, median palatine suture, incisive foramen
max. centrals anatomy
nasal fossa, max sinus
max lat. canine anatomy
max. sinus, zygoma
max premolar anatomy
max sinus, zygoma, max tuberosity, coranoid process
max molar anatomy
genial tubercles, lingual foramen
mand central anatomy
tori
mand lateral/canine anatomy
mental foramen, mental ridge, mand canal
mand premolar anatomy
mand canal, external oblique ridge, beg. of ramus
mand molar anatomy
increased focal spot size, decrease source-object distance, & increased object-film distance
what would cause increased magnification, decreased resolution and edge sharpness
as close as possible
according the principles of shadow casting, preferred object-film distance
as far as practical
according to principles of shadow casting, preferred source-object distance
parallel
according to principles of shadow casting, how should the film be placed in relation to the tooth?
perpendicular to the tooth and film
according to principles of shadow casting, how should the central beam be directed
paralleling; meets more principles of shadow casting
what periapical technique offers the best diagnostic quality?
shadow around the tooth
what is penumbra
beam is perpendicular to the imaginary line that bisects the angle formed by the long axis and the film
how is vertical angulation established with the bisecting technique
perpendicular to the film, parallel to the bite portion of the stabe
how is vertical angulation established with the paralleling technique
-bisecting – packet is as close to tooth as possible, but not parallel
-parallel – packet is parallel to tooth, further away
how does packet placement differ b/w bisecting and paralleling
ala-tragus line is parallel to the floor
what is the proper patient position for BW’s?
max arch ala-tragus parallel to floor
mand arch
mand arch
proper patient positioning for bisecting
doesn’t matter
proper patient positiong for paralleling
rectangular collimation and fast film speed
what is the best method of reducing radiation to the patient
6 ft
how far should the operator stand from the source of radiation
original, undeflected, useful beam
what is the primary beam
filtration and collimation
what is done to the primary beam to make is useful
reduce size and shape of beam
what is the purpose of collimation
lead
what is the collimator made out of
absorb long wavelengths / soft radiation
what is the purpose of filtration
aluminum
what are filters made out of
produced by internal barriers in tube head
(ex: glass and insulating oils)
(ex: glass and insulating oils)
what is inherent filtration
filters placed in PID after tubehead production
what is added filtration
1.5 mm
how much total filtration is required of x-ray machines that operate lower than 70 kVp
2.5 mm
total filtration required of x-ray machines that operate above 70 kVp
8-16 inches
what is the source-skin distance of x-ray machine that operates at 75 kVp
2.75 inches
what is the maximum size of the x-ray beam at the patients face
.25 mm
desired thickness of lead apron
depends on the needs of the patient, established after intraoral exam
how should the frequency of radiographic exposures be determined
every 6 mths
how often are BW taken on children with high risk
rapidly producing cells are more sensitive to radiation
how does the reproductive capacity of a cell correlate with radiosensitivity
WBC, RBC, immature reproductive cells
what 3 types of cells are most radiosensitive
nerve, brain, muscle
what 3 types of cells are most radioresistant
genetic cells
what types of cells must be effected in order for mutation to occur
coulombs/kilogram(C/kg)
&
Roentgen (R)
&
Roentgen (R)
what are the 2 units used to measure exposure to radiation
gray
&
Rad
&
Rad
what 2 unites are used to measure absorption
Sv & Rem
what 2 unites are used to measure biologic effect and dose equivalent
50 mSv or 5 REM
what is the annual MPD for radiation workers
5 mSv or .5 REM
1/10th dosage of gen. public
1/10th dosage of gen. public
what is the annual MPD for pregnant dental assistant
quantum of energy
what are photons
filament
what part of the x-ray machine is responsible for providing the electrons
-turn on machine
-adjust settings
-press exposure button
-filament heats up/thermoionic emmision
-electron cloud is formed
-electrons flow from cathode to anode
-electrons strike target
-energy is converted into x-rays and heat
-adjust settings
-press exposure button
-filament heats up/thermoionic emmision
-electron cloud is formed
-electrons flow from cathode to anode
-electrons strike target
-energy is converted into x-rays and heat
how are x-rays formed in the tubehead
copper stem, radiator and air space
what part of the x-ray machine helps remove heat
x-ray and heat
what is formed when high speed electrons strike the target
-invisible
-travel in straight lines
-no mass/weight
-travel and speed of light
-no charge
-interact w/ matter causing ionization
-can penetrate opaque tissues and structures
-can effect photographic film emulsion
-can effect biologic tissue
-travel in straight lines
-no mass/weight
-travel and speed of light
-no charge
-interact w/ matter causing ionization
-can penetrate opaque tissues and structures
-can effect photographic film emulsion
-can effect biologic tissue
list the properties of x-rays
chin down
what looking at a PANO what causes a big smile
-original packaging
-area sheilded from radiation
-50-70 degrees F
-area sheilded from radiation
-50-70 degrees F
how should x-ray film be stored
-locate retained roots
-locate unerrupted or impacted teeth
-evaluate for diseases and lesions
-locate foreign bodies
-reveal presence of salivary stones (sialothiths)
-aid in evaluating fractures
-size and shape of tori
-aid in examining patients with trismus (patient can only open mouth a few mm)
-evaluate borders of sinus
-examine cleft palates
-substitute for PA’s for young children or patient who can’t tolerate
-locate unerrupted or impacted teeth
-evaluate for diseases and lesions
-locate foreign bodies
-reveal presence of salivary stones (sialothiths)
-aid in evaluating fractures
-size and shape of tori
-aid in examining patients with trismus (patient can only open mouth a few mm)
-evaluate borders of sinus
-examine cleft palates
-substitute for PA’s for young children or patient who can’t tolerate
what are occlusal radiographs used to diagnose
every 4 weeks
how often should developing solutions be changed
1/5 exposure time for edentulous
how does exposure time for edentulous patients compare to dentulous patients
1/3-1/2
how does exposure time for children compare to that of an adult
x-rays that have been deflected from an object and have changed paths
what is scatter radiation
x-rays that have gone thru an object and are now a newer weaker beam
what is secondary radiation
5(n-18)
what equation is used to calculate the accumulated MPD
density
what is the term to describe the overall blackness of a radiograph
mA & time
what control factors effect the density of a radiograph
kVp
what control factors effect contrast
-decrease mA & time
if the kVp is increased from 75-90, what must be done to achieve a radiograph of comparible density
method should be compensated for bisecting or paralleling
if the source-object distance is cut from 16 to 8 , what must be changed to compensate
decrease kVp by 15 and double exposure time
10 mA 60 impules 75 kVp
10 mA 60 impules 75 kVp
You take a radiograph using 10 mA 30 impulses and 90 kVp, your dentist wants a radiograph with increased contrast and equal density. What settings would you use?
PANO
which projection is used to view sinuses
erythema
what is the earliest sign of radiation exposure
soft tissue, air space
which anatomical structures appear radiolucent
dentin, enamel, bone
which anatomical structures appear radiopaque
time b/w exposure and 1st clinically observable symptoms
what is the latent period
Roentgen
who discovered x-rays
erythema, vomitting, nausea, hemorrage, diarrhea, hair loss
what are the short term effects of radiation exposure
cancer, cateracts, embryologic defects, genetic mutations, low birth weight
what are the long term effects of radiation exposure
lateral cephalometric
what exposure is taken to determine jaw relationships in ortho treatment planning
-detect pathological lesions
-establish position of mental foramen
-establish position of mand canal
-determine quality & quantity of alveolar bone present
-establish position of mental foramen
-establish position of mand canal
-determine quality & quantity of alveolar bone present
what is the purpose of taking radiographs of an edentulous patient
mand occlusal
what exposure would be useful in identifying salivary stones in the submandibular gland
step-wedge or test film
what device is used to check quality of processing chemicals
DEHNR
what NC agency is resposible for monitoring dental x-ray equipment
cosmic , naturally occuring radiation from earth, radiation for radioactive materials
what are common sources of background radiation
x-rays hit phosphor screen creating florescent light that exposes the film
how are indirect exposure films exposed
dentsply rinn, XCP, XCP-DS, flow dental RAPD
3 film holding devices used for paralleling
dentsply rinn stabe, BAI, dental SUPA
3 film holding devices used for bisecting
labial
what is the ADA approved method of mounting dental radiographs
aka general radiation; stopping or slowing of the electrons of the cathode stream as they collide with the nuclei of the target atoms
what is the bremsstrahlung radiation
a form of radiation originating from an atom following removal of an electron or excitation of an atom
what is characteristic radiation
-particulate radiation: made of protons, neutrons, electrons and alpha and beta particles; has mass
-electromagnetic radiation: made of photons; no mass
what is the major diff. b/w particulate and electromagnetic radiation
periapical examination, paralleling technique
which radiographic technique records the most accurate image of crowns, roots, and supporting structures in a selected area?
periapical
A patient complains of pain in the upper molar region. What radiographic exposure should be made?
short
What type of x-rays have greater penetrating power, long or short wavelength?
failed safelight test, suggesting that the safelight conditions in the darkroom are fogging the film
in the darkroom, you unwrap a film and place a coin on top of the film for several minutes. when you process the film, you notice a slight, well-defined white circle on the film. what does this mean?
-overdevelopment
-temp. too high
-time too long
-temp. too high
-time too long
-developer concentration too high
-inadequate fixation
-accidental exposure to light
-improper safelighting
what would cause a properly exposed film to appear dark?
b/c of its stability to produce a large volume of radiographs in a short amount of time
what are automatic processors faster than manual processing?
insufficient or improper washing
when looking at radiographs that were taken several years ago, you notice a brownish stain which makes interpretation difficult. what caused this?
release of electrons when a material such as tungsten is heated to incandescence.
electrons are boiled off from the cathode filament in the x-ray tube when electric current is passed through it
electrons are boiled off from the cathode filament in the x-ray tube when electric current is passed through it
what is thermionic emission
copper stem
tungsten target
radiator
tungsten target
radiator
what parts of the x-ray machine are included in the anode circuit
cathode
filament
focusing cup
filament
focusing cup
what parts of the x-ray machine are included in the cathode circuit
far object-image receptor distance
what factors would decrease edge sharpness and increase magnification
no exposure to x-rays,
electrical failure,
malfunction of x-ray machine,
or processing errors
electrical failure,
malfunction of x-ray machine,
or processing errors
you process a set of BW’s in the automatic processor. three of the BW’s are of good quality, but fourth is completely blank. what probably caused this?
premature contact w/ developing chemicals.
drops of developer or fixer that splash onto the work area and came in contact with the film.
drops of developer or fixer that splash onto the work area and came in contact with the film.
what looking at manually processed films, you notice small black spots on the films. what caused those spots?
dark film is from over exposure and improper packet placement for strange looking teeth and not being able to determine what film is
when mounting a FMS, you notice that one film is blank. another film is dark, the teeth look strange, and it is difficult to determine what film it is. what do you think happened?
-take 14 radiographs
-omit the BW
-paralleling should be technique of choice
-panoramic might be better than FMS
-omit the BW
-paralleling should be technique of choice
-panoramic might be better than FMS
your dentist asks you to take a FMS on a 65 yr old edentulous patient. how many exposures will you take? which exposures are not necessary? what intraoral technique will you use? what might be better than a FMS?
-bisecting was used b/c of the distortion of the elongated root
-the roots appeared long b/c the vertical angulation was inadequate
-the roots appeared long b/c the vertical angulation was inadequate
when viewing a periapical radiograph, you notice that the image of the tooth is extremely long and well defined; however the apices are missing. what technique was used to take the radiograph? what caused the roots to appear long?
-extraoral film
with what type film are intensifying screens used?
green light sensitive film (Kodak T-Mat)
what type of film are rare earth screens paired with
blue light sensitive films
what type of film are calcium tungstate screens paired with
not as sharp and detailed as the intraoral image
how does resolutiong and detial of a panoramic radiograph compare with that of PA’s and BW’s
oral piercings, earings, glasses, necklaces, facial piercings, hair pins, hearing aids, dentures, and retainers
what must a patient remove before taking a PANO
-max teeth are longer
-max molars have 3 roots, mand molars have 2 roots
-most roots curve toward the distal
-occlusal plane is straight or curved slight towards distal
-max molars have 3 roots, mand molars have 2 roots
-most roots curve toward the distal
-occlusal plane is straight or curved slight towards distal
when mounting dental radiographs, what is the best way to differentiate max and mand films?
the mental ridge
when interpreting radiographs, you notice a radiopaque extension or spur off the proximal surface of #30. what do you think this is?
located on the tooth surface that contacts the adjacent tooth
in which area of the tooth is interproximal caries often seen
rectangular collimations
what type PID significantly reduces exposure to the patient
25
when using D speed film, you use 50 impulses of radiation. how many impulses would you use with E speed film?
short-term dose
what is a large dose of radiation given over a short period of time
long-term dose
what is small doses of radiation given over a long period of time
chronic low-level exposures/long term dose; causing cancer, cataracts, low birth weight, genetic mutations, and embryological defects
which dose of radiation is more biologically damaging
focal spot
what is the name for the part of the target that is struck by electrons
higher temp. increases film fog, so radiographer should consult a time-temp. development chart to adjust developing time appropriately; developing time will decrease
when manually processing dental film, you notice the temp. has gotten warmer as the day progressed. how should the developing time be changed?
thyroid collar, lead and lead-equivalent sprons are availaable with or without an attached thyroid collar
what is the best method of protecting the thyroid gland from radiation?
only when necessary to help the dentist diagnose and treat oral diseases; elective xrays should be postponed until after delivery
when should radiographs be taken on a pregnant patient
patient positioning
what is the most important step in panoramic radiography
patient’s dental arches; maxilla and mandile
what is the area of the skull that is in focus on a pano
periodically examining cassettes and intensifying screens; extra oral cassettes should be checked for warping and light leaks
what quality control procedures should be performed on xray cassettes
duplicate, which will go to the insurance comp.; office keeps best copy
an insurance company requests a patient’s radiographs when examining a dental clain. you only have one copy of the radiographs. what should you do
the emulsion side of the film is placed against the orginal radiograph with the nonemulsion side up
when duplicating radiographs, what side of the duplicating film is in contact with the radiograph to be duplicated
increase the exposure time
when viewing a duplicated radiograph, you notice that the duplicate is too dark. what should you do to duplicating time to lighten the film
negative
what type of angulation is used when taking radiographs of the mand. arch
as low as reasonably achievable
what does alara stand for
document patient’s refusal and have them sign
your dentist recommends that a patient have xrays taken, bu the patient refuses. what should be done
do not suggest gagging, emphasize, use power of suggestions, apply distractiong techniques, give patient breathing instructions, reduce tactile stimuli, being exposures in the ant. region, place image receptor firmly and expertly, confuse the senses, utilize special products; substitute extraoral as needed
what can be done to minimize gagging when taking radiographs
film badges
what is the most commonly used personnel monitoring devide for dental offices
patient’s name, date, and other pertinent info
what info should be recorded on the dental radiographic mount
large blank space is due to reversed image error or chemical contamination
missing apices is due to inadequate VA
when viewing a radiograph, the tooth looks normal in size and shape; however, there is a large blank space at the incisal edge and the apices are missing. what caused this error
excessive VA w/ PID positioned too steep enough away from zero degrees
what causes teeth to appear very short and distorted
central ray
what is the x-ray at the center of the primary beam called
extra oral
what type film is faster, intraoral or extraoral
sterilize film holder devices or discard disposable image receptor holding devices
how are stabe film holders sterilized b/w uses
eyewear, mask, and gown
what PPE should be worn when exposing radiographs
on the back side of the tori
when taking a paralleling radiograph of a patient with palatal tori, where is the film places
kVp
what controls the speed with which the electrons travel from the cathode to the anode
movement caused by the patient, slippage of the image receptor, or vibration of the tube head
what would cause the radiographic image to be blurred
reg. replenishment and changing out expired solutiong with fresh chemicals at reg. intervals; monitor strength of chemicals on a daily basis
what can be done to increase the life span of processing solutions
gently agitating the hanger up and down a few times
what can be done to prevent air bubbles from being trapped on the surface of films during manual processing
ionization
how does radiation effect cells
remove silver
what must be done to xray fixer priod to disposal
check the processing chemical, particularly the developer
you notice that the xrays you process are becoming successively lighter than the quality control film you compare it to. what should you do
mandibular occlusal
what radiographs are used to locate a salivary stone in the submandibular duct
occlusal
what radiographs are used to determine if a foreign object is located facially or lingually
patient positioned too far foward in the focal trough
you notice on a PANO that the ant. teeth appear narrow and out of focus. what caused this
soft cloth, non abrasive cleaner
what is used to clean the screens inside of a cassestte
15 impulses
how many impulses are in .25 seconds
2.75 inch
using a 16 inch cone focal-film distance, the diameter of the beam measured at the patient’s face should be no larger than
higher kVp = low exposure
how does kVp affect patient exposure
lighter image, patient exposed to larger beam which will increase exposure
when taking a radiograph, you pull the end of the PID away from the patients face about 6 inches. how will this affect the radiographic image and patient exposure
focal spot size, target-image receptor distance, object-image receptor distance, motion, screen thickness, screen-film contact, and crystal/pixel size of intraoral image receptors
what factors affect the sharpness of the radiographic image
patient movement
what is the most likely cause of a film with very poor definition
enamel, dentin, and bone
what anatomical structures appear radiopaque on a dental radiograph
air space and soft tissues
what anatomical structures appear radiolucent on a dental radiograph
50 mSv (5rem)
what is the max. permissable fose for radiation workers in systeme interventional units
clinical exam
what should be done prior to ordering radiographs for a patient
scatter/secondary radition
what is the main source of radiation exposure to the operator
premature contact with developer
after processing exposed dental film, you notice dark spots on the film. what caused this
panoramic cape
what type lead apron should be used when taking PANO radiographs
mandibular lateral/central
in which pericapical projection will the mental ridge be visible
highest of the 2 ridges, about the level of the cervical 3rd, behind the 2nd and 3rd molars
on a mandibular molar PA , where is the mylohoid ridge located
all of the ant. teeth will appear blurred and narrowed in width
when taking a PANO radiograph, the patient is placed too far into the machine. how will the radiograph appear
patient positioned too far to the left
when viewing a PANO, you notice that the right TMJ is magnified, bu the left TMJ is normal. what caused this error
positioning the arches too far foward
when viewing a PANO, you notice that a lot of spine shows on both side of the film, what caused this
mand. foramen
which anatomic feature is visible on a PANO, bu not on a PA
zygoma will be radiopaque, max. sinus will be a large area of radiolucency
how can you differentiate the zygoma from the max sinus in a max posterior PA
insufficient or improper washing
you notice that a radiograph taken several months ago is brown and spotted. what happened
before fixing
a properly exposed film appears completely black. when was is exposed to white light
clear/blue in the area of overlap b/c fixer will not remove all crystals
when processing, two films overlap in the developer, but not in the fixer. how would the films appear
didn’t push button completely
you process four BW films. three of the films appear normal, but one is clear. what happened
rectangular collimation
what is the best way to reduce exposure to patient
increase the area of radiation exposure
when taking a radiograph, you pulls the cone out about 6 inches from the patient’s face. what is the result
the less the patient is exposed, the less the operator is exposed
how does reducing exposure to the patient benefit the operator
move farther from the radiation
how can exposure to the operator be reduced
occlucal
what film would be used to locate a foreign body in the bucco-lingual relationship
provides more info. about the location of tori, impacted and malpositioned teeth and the calcification of soft tissues
what is the major use of cross sectional occlusal radiograph
images conditions of the teeth and supporting structures when a larger area than a PA is needed; provides more info. than a PA about the alveolar crest and apical areas
what is the major use of topographical occlusal radiographs
evidence based selection criteria
how do you determine how often to take radiographs
take FMS on all new patients; recall adults with no sig. med. history only require BW and PA, if indicated
how often should an FMS be taken on an adult with no significant medical history
CCD (direct)
CMOS (direct)
PSP (indirect)
CMOS (direct)
PSP (indirect)
what are three types of image receptors used in digital radiography
white blood cells
red blood cells
immature reproductive cells
epithelial cells
connective tissue cells
bone cells
nerve cells
brain cells
muscle cells
red blood cells
immature reproductive cells
epithelial cells
connective tissue cells
bone cells
nerve cells
brain cells
muscle cells
list the cells from most sensitive to least sensitive
the most distal tooth should be captured in full as well as a few mm of bone level behind the most distal tooth
when viewing a molar BW, what should be on the distal of the film
stop taking xrays and evaluate all equipment and techniques to ensure safety
your film badge report shows that you have received a small amt. of radiation. what should you do
1/6th of a second
you use an exposure time of 10 impulses. how many seconds is this
the wave length will be shorter, the quality and energy of the beam will be higher and the contrast will be lowe.
the image will also have a higher density
the image will also have a higher density
you change you kVp from 90 to 70 and leave all other factors the same. what is the result
1/4 as intense
you change from an 8 inch to an 16 inch focal film distance. how is the intensity of the beam affected
for every 30 films processed 6-8 oz should be taken out and replaced with fresh solution
how often must you replenish the solutions in an automatic processor
maintain acidity & alkalinity & prevent oxidation,
what is the purpose of replenishing the developer solution
#2
what size film is used to take an occlusal radiograph of a 6 yr old child
#0
what size film is used to take a BW on a 3 yr. old
MRI
what radiograph is used to show contrast in soft tissues
#1 or #2
placed so the edge of the receptor lines up behind the distal of the canine before the eruption of the permanent 2nd molar;
after the eruption of the perm. 2nd molar, 2 posterior PA’s should be taken per quadrant
placed so the edge of the receptor lines up behind the distal of the canine before the eruption of the permanent 2nd molar;
after the eruption of the perm. 2nd molar, 2 posterior PA’s should be taken per quadrant
what size and how is the film places when taking a molar PA in the mixed dentition
