dental xray film processing Flashcards
series of steps that produce visible permanent image on a dental radiograph
film processing
5 steps in manual film processing
development, rinsing, fixation, washing, drying
hydroquinone (developing agent)
builds contrast, brings out the black tones, temp sensitive
elon (developing agent)
brings out the image, generates the many shades of grey. Not temp sensitive
sodium sulfite (preservative)
prevents solution from oxidizing
sodium carbonate (accelerator)
serves as activator/accelerator
potassium bromide (restrainer)
controls/restrains developer. Inhibits fogging of the lighter areas
rinse (manual processing only)
to remove the developer from the film and stop the development process
fixer solution
remove the unexposed unenergized silver halide from the film emulsion
fixer solution 4 basic ingredients
sodium thiosulfate, sodium sulfite, potassium alum, acedticacid/sulfuric acid
sodium thiosulfate (fixing agent)
clears the film , dissolves unexposed, underdeveloped silver bromide
potassium alum (hardening agent)
hardens and shrinks the gelatine in the emulsion , protects film from scratches
sulfruic/acedic acid
neutralizes the alkaline developer remaining on the film
developer has
a basic PH level
fixer has
an acidic PH level
washing
removes all excess chemicals from the emulsion
drying (final step)
film must be completely dry before handling for mounting & viewing
darkroom
must be light tight, X-ray film is extremely sensitive to visible light , can cause fogging
safelights
provide adequate light so you can see what you are doing , have special filters that produce low-intensity lighting
safelights must be how far away
4 feet away and no more than 7 watts
orange
intraoral
red
intra/extra oral
optimum temp for development
68 degrees F
advantages for automatic processor
less time required, time/temp automatically controlled, less equipment, less space
made by directing a light source through the original film
duplicating film
increase amount of time the light is on for a
lighter duplicate
decrease the amount of time the light in on for
darker duplicate
dark film (overdeveloped) results from
developer too hot
Too much time in the developer
light film (underdeveloped) results from
developer too cold
not enough time in developer
contaminated developer
pebbly or web like surface appearance of the film , results from sudden temp change
reticulation
dark spots (developer contamination)
when developer solution comes in contact with the film before processing
light spots (fixer contamination)
drops of fixer accidentally contact the film before processing
yellowish brown stain
appear due to not properly washing after fixation
failure to agitate the film as it is placed in a manual developer , appears radiopaque
air bubbles
films are fed into automatic processor too quickly .results in dark areas on the film, may appear green/brown
films overlapped
dark lines
automatic processor is not cleaned properly , rollers become dirty, black lines on film
scratched film-white lines
occurs from incorrect handling and fingernails
black crescent shaped artifact
fingernail artifact
film is removed too quickly from either packet, box or cassette. Results in black lines, dots, tree branch patterns
static electricity
accidental exposure to white light before developing
light leak
image looks gray, lacking in detail and contrast, caused by leaks in darkroom, expired films, improper film storage
fogged film
image appears stretched and distorted, may be bent due to curvature of pt mouth
bent film
PID is misaligned and xray beam is not centered over the receptor
cone cut
cardboard, plastic or vinyl holder that is used to support and arrange dental radiographs in anatomic order
film mount
an opening on the outside of the processor housing used to insert unwrapped films into the automatic processor.
film feed slot
encases all the component parts of the automatic processor.
processor housing
t:f/ automatic processor requires dailyor weekly cleaning
true
what film is used to clean the roller of the automatic processor
extra oral film
t:f each week rollers must be removed then soaked for 10-20 mins
true
black areas
created by deposists of black metallic silver
white areas
result from removal of unexposed crystals
purpose of fixer is to
remove unexposed, unenergized crystals from film emulsion
4 basic ingredients
developing agent, preservative , accelerator, restrainer
developing agents are
hydroquione , elon
preservative
sodium sulfite
accelerator
sodium carbonate
restrainer
potassium bromide
preservative does what
prevent developer solution from oxidizing in presence of air
accelerator does what
softens gelatin of the film emulsion
purpose of restrainer
control the developer and prevent it from developing unexposed crystals
hardening agent chemical
potassium alum
fixing agent chemicals
sodium thiosulfate , ammonium thiosulfate
