What is quality assurance in the Dental office?
Special prodedures that are used to ensure the production of high-quality diagnostic radiographs
Who is ultimately responsible for administration of quality assurance?
How can the dental radiographer aid in implementation of administration of quality assurance?
By being knowledgable of the quality assurance plan
Quality control tests
specific tests used to monitor dental radiograph equipment
What do quality control tests monitor?
- Dental x-ray machine
- Dental x-ray film
- Screens and cassettes
- Dark room lighting
- processing equipment
- processing solutions
- Viewing equipment
Describe quality administration procedures
- Description of plan
- Assignment of duties
- monitoring schedule
- maintenance schedule
- record-keeping logs
- evaluation and revision plan
- in-service training
What must you do to care for x-ray machine?
check for calbration, and adjust for accuracy
how often must you test dental x-ray machine?
once a year
What does x-ray machine testing look for?
- minor malfuncionts
- machine output variations
- inadequate collimation
- tubehead drift
- timing errors
- inaccurate kilovoltage and milliamperage readings
How do you test for freshness of x-ray film?
process one unexposed film
How will a fresh unexposed film appear after testing?
clear with a slight blue tint
How will an unfresh film appear after testing? Why does it appear this way?
- appears fogged
- expired film, improper storage, exposed to radiation
What are extraoral screens used within a cassette holder examined for? how do you avoid this condition?
- dirt or scratches
- clean monthly with recommended cleaners
- appy astistatic solutions
What are cassette holders examined for?
- worn closures
- light leaks
- warping resulting in fogged or blurred radiographs
How do you check for adequate film-screen contact?
flim-screen contact test using wire mesh
How does the film appear if there is adequate film-screen contact?
wire mesh image has uniform density
How does the image appear if there is inadequate film-screen contact?
- the film exhibits varying densities
- areas of poor contact appear darker
What should you examine on the radiograph viewing equipment?
- dirt and discoloration of plexiglass
- should emit uniform and subdued light
How do you care for radiograph viewing equipment?
- wipe daily
- replace discolored plexiglass
- replace blackened flourescent bulbs
Why is film processing one of the most critical areas in quality control?
because in can result in a large number of nondiagnostic film
What must the dark room be tested for? and how often?
- light-tightness and proper safe-lighting
- every 6 months
How do you check for light-tightness in the dark room
turn off all the light including safe-light, and observe room for light leaks
How do you correct light leaks in the dark room?
with weather stripping or black tape
How do you test the safe light?
with the coin test method (after the light leak test has been performed)
How will the film appear if there is proper safe lighting?
no visible image is present on the processed radiograph
How wil the film appear if there is improper safe lighting?
the image of the coin and fogged background appear on the film
how often must the proccessing equipment be monitored?
What do you check in the processing equipment?
- water circulation system
- solution levels
- replenishment system
- processing time
How do you test to see if the processing equipment is running properly?
run 2 films, one exposed, one not exposed
How will the films appear if the processing equipment is running properly?
- exposed film-pure black
- unexposed film- clear bluish tint and dry
How will films appear if the processing equipment is not functioning properly?
- exposed flim- not black and dry
- unexposed film- not clear and dry
Describe general care for processing solutions
- replenish daily
- change every 3-4 weeks
- evaluate daily before patient films are run
Name 2 methods for checking developer strength
- reference radiograph
- stepwedge radiographs
processed under ideal conditions and then used to compare the film densities of radiographs processed daily
What do matched densities in reference radiograph testing indicate?
developer solution strength is adequate
What do unmatched densities on reference radiograph test indicate?
- if dinsities on daily radiographs are light-developer is weak or cold
- if densities on daily radiographs are dark-developer is too strong or hot
Stepn wedge radiograph
process one of twenty exposed radiographs under ideal conditions
When the fixer solution is at full strength how long should it take the film to clear?
no longer than 2 minutes
Name the 3 types of radiographic examination that use intraoral film
- periapical exam
- inter proximal exam
- occlusal exam
Periapical exam purpose
exam entire tooth and supporting bone
periapical film type
PA film-shows root and apex and surrounding bone
technique used for PA exam
- paralleling techniqu
- bisecting technique
interproximal exam purpose
- examine crowns of maxillary and mandibular teeth on a single film
- examine adjacent tooth surfaces and crestal bone
interproximal exam film type
bite-wing film including bitewing tab
interproximal exam technique used
Occlusal exam purpose
to examine large area of jaw on one film
occlusal exam type
occlusal film-pt bites on film
occlusal exam technique
Complete Mouth Radiographic series
series of intraoral dental radiographs that show all the tooth-bearing areas of the maxilla and mandible
what film types does the CMRS include?
- 4 maxillary molar-premolar PA's
- 3 maxillary anterior PA's
- 4 bitewing films
- 4 mandibular molar-premolar PA's
- 3 mandibular anterior PA's
- include edentulous areas as well
When is the CMRS appropriate?
new adult pt. presents with clinical evidence of generalized dental diseas, or a history of extensive dental treatment
Diagnostic criteria for intraoral radiographs
- images with opyimum density, contrast, definition and detail
- images with least amount of distortion as possible-same size and shape as tooth
- FMX must show include all tooth-bearing areas
- PAX must show entire crown and root of teeth being examined as well as 2-3 mm beyond root apices
- BWX must show open contacts or interproximal tooth surfaces- not overlapped
Prescribing of dental radiographs is based on_______. Professional judgement is made by_____________. indentifies what 3 things?
- pt. needs
- the dentist
- number, type, and frequency
moving or lying in the same plane (railroad tracks)
intersecting or forming a right angle
to cut across or through
angle of 90 degrees formed by 2 perpendicular lines
long axis of tooth
imaginary line that divides tooth longitudinally into 2 equal halves
central portionof the beam of x-radiation
Describe the principles of the paralleling technique
- film is placed parallel to the long axis of tooth
- central ray of the x-ray beam is directed perpendicular to the film and long axis
- film holder must be used
- object-film distance must be increased to keep film parallel
- target film distance must be increased as a result of object-film distance
What must you increase the target-film distance to to compensate for magnification and loss of definition?
16" using long cone or PID
What does rectangular collimator do?
reduces radiation exposure to pt. by 70%
Name 5 types of film holders
- Rinn XCP
- precision film holders (collimator)
- Stabe bite block (disposable)
- EEZEE-grip film holder (Snap-a-ray)
- hemostat with bite-block
Size of film used in anterior regions
Size of film used in posterior regions
- size 2
- placed horizontally
positioned to cover teeth examined
positioned parallel to long axis of tooth, and away from tooth
rays must be perpendicular to film and long axis of tooth
central rays must be directed through the contact areas between the teeth
x-ray beam must be centered on the film to ensure that all areas of the film are exposed
Describe pt. preparation for radiographs
- explain radiographic procedure
- adjust chair to upright and comfortable height
- adjust headrest so upper arch is parallel to floor and midline is perpendicular to the floor
- place lead apron with thyroid collar
- remove all objecs from mouth and glasses
Describeradiographic equipment preparation
- set kVp and mA
- open sterilized package and assemble
- insert film packet into holder
What is the exposure sequence for anterior teeth?
- start with maxillary right canine
- move to maxillary right lateral and central incisor
- move to left maxillary central and lateral incisor
- move to left maxillary canine
- move to left mandibular canine
- move to mandibular incisors
- move to right mandibular canine
Describe the sequence for posterior exposure sequence
- assemble XCP for maxillary right premolars
- then move to maxillary right molars
- then mandibular left premolars
- then mandibular left molars
- then assemble XCP form maxillary left premolars
- then move to maxillary left molars
- then mandibular left premolars
- then mandubular left molars
Maxillary canine exposure
should show center of canine, mesial of 1st premolar, and distal of lateral incisor
Maxillary incisor exposure
centered on contact between lateral and central incisor
mandibular canine exposure
centered on canine, shows mesial of 1st premolar and distal of lateral incisor
mandibular incisor exposure
centered on contact between central incisors- show all lateral and central incisors
maxillary premolar exposure
centered on second premolar, show from canine to 1st molar
maxillary molar exposure
centered on second molar, show from distal of 2nd premolar to 3rd molar
mandibular premolar exposure
center film on second premolar, show from canine to first molar
mandibular molar exposure
center on 2nd molar, show all three molars
What can you do to modify the paralleling technique in case of shallow palate?
Use cotton roll if tilt exceeds 20 degrees
What are the advantages of the parallel technique?
- Accuracy-image that has dimensional accuracy and is free of distortion and exhibits maximum detail
- simplicity-simple and easy to use and learn
- duplication- easy to duplicate and repeat comparisons of series have great validity
What are the disadvantages of the paralleling technique?
- film placement is difficult
- can be uncomfortable to patients
Film exposure errors
- result in nondiagnostic film
- additional radiation to the pt. if retake is necessary
How does an unexposed film appear? Why did this happen?
- film appears clear
- occured becuase the film was not exposed
How does a film exposed to light appear? What caused this
- the film was exposed to white light
How does an overexposed film appear? Why did this happen
- images are darker
- excessive exposure time, kVP, or mA
How does an underexposed film appear? Why did this happen
- image is light
- inadequate exposure time, kVP, or mA
How might a film appear if incorrect film placement was performed?
- absence of apices- film was not positioned into pt. mouth to cover apices
- occlusal plane appears tipped or tilted - the edge of the film was not placed parallel to the incisal-occlusal surface of teeth
How does the film appear if incorrect horizontal angulation was used?
contacts on teeth appear overlapped
How do forshortened images appear? Why did this happen?
- teeth appear short with blunted roots
- verticle angulation was excessive (too steep)
How do elongated images appear? Why did this happen?
- long distored teeth appear on film
- vertical angulation was insufficient (too flat)
How does a cone cut appear? Why did this happen?
- unexposed area appears on film
- PID was not aligned with the XCP
name 6 types of miscellaneous technique errors
- film bending
- film creasing
- double exposure
- reversed film