DH Radiology

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?

The dentist

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 machineDental x-ray filmScreens and cassettesDark room lightingprocessing equipmentprocessing solutionsViewing equipment

Describe quality administration procedures

Description of planAssignment of dutiesmonitoring schedulemaintenance schedulerecord-keeping logsevaluation and revision planin-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 malfunciontsmachine output variationsinadequate collimationtubehead drifttiming errorsinaccurate 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 foggedexpired 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 scratchesclean monthly with recommended cleanersappy astistatic solutions

What are cassette holders examined for?

worn closureslight leakswarping 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 densitiesareas of poor contact appear darker

What should you examine on the radiograph viewing equipment?

dirt and discoloration of plexiglassshould emit uniform and subdued light

How do you care for radiograph viewing equipment?

wipe dailyreplace discolored plexiglassreplace 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-lightingevery 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?

Daily

What do you check in the processing equipment?

water circulation systemsolution levelsreplenishment systemtemperaturesprocessing 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 blackunexposed film- clear bluish tint and dry

How will films appear if the processing equipment is not functioning properly?

exposed flim- not black and dryunexposed film- not clear and dry

Describe general care for processing solutions

replenish dailychange every 3-4 weeksevaluate daily before patient films are run

Name 2 methods for checking developer strength

reference radiographstepwedge radiographs

Reference radiograph

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 coldif 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 examinter proximal examocclusal 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 techniqubisecting technique

interproximal exam purpose

examine crowns of maxillary and mandibular teeth on a single filmexamine adjacent tooth surfaces and crestal bone

interproximal exam film type

bite-wing film including bitewing tab

interproximal exam technique used

bitewing technique

Occlusal exam purpose

to examine large area of jaw on one film

occlusal exam type

occlusal film-pt bites on film

occlusal exam technique

occlusal 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's3 maxillary anterior PA's4 bitewing films4 mandibular molar-premolar PA's3 mandibular anterior PA'sinclude 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 detailimages with least amount of distortion as possible-same size and shape as toothFMX must show include all tooth-bearing areasPAX must show entire crown and root of teeth being examined as well as 2-3 mm beyond root apicesBWX 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. needsthe dentistnumber, type, and frequency

Parallel

moving or lying in the same plane (railroad tracks)

Perpendicular

intersecting or forming a right angle

intersecting

to cut across or through

right angle

angle of 90 degrees formed by 2 perpendicular lines

long axis of tooth

imaginary line that divides tooth longitudinally into 2 equal halves

central ray

central portionof the beam of x-radiation

Describe the principles of the paralleling technique

film is placed parallel to the long axis of toothcentral ray of the x-ray beam is directed perpendicular to the film and long axisfilm holder must be usedobject-film distance must be increased to keep film paralleltarget 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 XCPprecision 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 1placed vertical

Size of film used in posterior regions

size 2placed horizontally

Film placement

positioned to cover teeth examined

Film position

positioned parallel to long axis of tooth, and away from tooth

Vertical angulation

rays must be perpendicular to film and long axis of tooth

Horizontal angulation

central rays must be directed through the contact areas between the teeth

film exposure

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 procedureadjust chair to upright and comfortable heightadjust headrest so upper arch is parallel to floor and midline is perpendicular to the floorplace lead apron with thyroid collarremove all objecs from mouth and glasses

Describeradiographic equipment preparation

set kVp and mAopen sterilized package and assembleinsert film packet into holder

What is the exposure sequence for anterior teeth?

start with maxillary right caninemove to maxillary right lateral and central incisormove to left maxillary central and lateral incisormove to left maxillary caninemove to left mandibular caninemove to mandibular incisorsmove to right mandibular canine

Describe the sequence for posterior exposure sequence

assemble XCP for maxillary right premolarsthen move to maxillary right molarsthen mandibular left premolarsthen mandibular left molarsthen assemble XCP form maxillary left premolarsthen move to maxillary left molars then mandibular left premolarsthen 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 detailsimplicity-simple and easy to use and learnduplication- easy to duplicate and repeat comparisons of series have great validity

What are the disadvantages of the paralleling technique?

film placement is difficultcan be uncomfortable to patients

Film exposure errors

result in nondiagnostic filmadditional radiation to the pt. if retake is necessary

How does an unexposed film appear? Why did this happen?

film appears clearoccured becuase the film was not exposed

How does a film exposed to light appear? What caused this

blackthe film was exposed to white light

How does an overexposed film appear? Why did this happen

images are darkerexcessive exposure time, kVP, or mA

How does an underexposed film appear? Why did this happen

image is lightinadequate 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 apicesocclusal 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 rootsverticle angulation was excessive (too steep)

How do elongated images appear? Why did this happen?

long distored teeth appear on filmvertical angulation was insufficient (too flat)

How does a cone cut appear? Why did this happen?

unexposed area appears on filmPID was not aligned with the XCP

name 6 types of miscellaneous technique errors

film bendingfilm creasingphalangionadouble exposuremovementreversed film