1. Quality Assurance in the Dental Office
Chapter 10
Quality Assurance in the Dental Office

2. Dental Radiography Questions
What quality control tests and quality administration procedures may be used in the dental office?
How are the quality control tests conducted and how are the results analyzed?
What are the basic elements of a quality administration plan?

3. Dental Radiography Chapter 10 Reading:
Iannucci & Howerton (pp )

4. Dental Radiography Chapter 10 Outline
Quality Assurance in the Dental Office
Quality control tests
Quality administration procedures
Operator competence

5. Introduction Purpose Iannucci & Howerton (pp. 111-112) (Box 10-1)
To introduce the dental radiographer to quality control tests that are used to monitor dental x-ray equipment, supplies, and film processing
What are some quality control tests that ensure x-ray equipment meets safety standards?
Although the dentist is responsible for ensuring that these things are done, the tasks themselves are typically left for the radiographers.

6. Quality Control Tests Specific tests used to maintain and monitor
Dental x-ray equipment
Supplies
Film processing

7. Equipment and Supplies
Iannucci & Howerton (pp )
Dental x-ray machines
Dental x-ray film
Screens and cassettes
Viewing equipment
Quality control tests are necessary to monitor all dental x-ray machines, film, screens and cassettes, and viewing equipment.
Everything must be in good working order to produce a diagnostic radiograph.

8. Dental X-ray Machines
Iannucci & Howerton (p. 112) (Box 10-2)
All dental x-ray machines must be inspected and monitored periodically.
Local and state regulatory agencies provide inspection services.

9. Dental X-ray Film Fresh film test Prepare film. Process film
Unwrap one unexposed film from a newly opened box.
Process film
Use fresh chemicals to process the unexposed film.
Each box should be checked for freshness before it is used.

10. Dental X-ray Film Fresh film Fogged film
The processed film appears clear with a slight blue tint.
Fogged film
The processed film is fogged and may be expired, improperly stored, or exposed to radiation.
What does a fresh film look like compared to a fogged film?

11. Screens and Cassettes Screens Cassette holders
Extraoral intensifying screens should be examined for dirt or scratches.
Screens should be cleaned monthly.
Cassette holders
Examine for worn closures, light leaks, and warping.
A commercially available cleaner should be the only type of cleaner used on the screens.
An antistatic solution should be applied to the screens after they have been cleaned.

12. Screens and Cassettes Film-screen contact test
Iannucci & Howerton (pp ) (Fig. 10-1)
Film-screen contact test
Insert film in cassette holder.
Place a wire mesh test object on top of loaded cassette.
Position PID with a 40-inch target-film distance.
Expose the film using 10 mA, 70 kVp, and 15 impulses.
Process the exposed film.
View the film on a viewbox in a dimly lit room at a distance of 6 feet
The exposed film will either be of adequate contact or nonadequate contact, depending upon the density that is exhibited.

13. Viewing Equipment Viewbox Iannucci & Howerton (p. 113) (Fig. 10-2)
A light source used to view dental radiographs
Also referred to as an illuminator or lightbox.
The plexiglass on the viewbox should be wiped clean daily.
Should reflect a uniform and subdued light. If it does not, then the bulbs or plexiglass may need to be replaced.
Scratched plexiglass or dim bulbs can make radiographs difficult to read.

14. Film Processing Darkroom lighting Processing equipment
Iannucci & Howerton (pp )
Darkroom lighting
Processing equipment
Processing solutions
This is one of the most critical areas in quality control and requires daily monitoring.

15. Darkroom Lighting Darkroom must be checked every 6 months.
Prepare darkroom.
Examine darkroom.
The darkroom must be “light-tight.”

16. Darkroom Lighting No light leaks Light leaks
Proceed with film processing.
Light leaks
Correct these with weather stripping or black tape.
Light leaks must be corrected with weather stripping or black tape.
Most light leaks are seen around the door, through the seams of the walls or ceiling, of through a vent or keyhole.

17. Safelighting Coin test Prepare darkroom. Prepare film.
Place a coin on an unwrapped, unexposed film.
Turn on the safelight for 3 to 4 minutes.
Remove the coin and process the film.
If the image appears fogged, the safelight is not safe to use with that type of film.

18. Safelighting Proper safelighting Improper safelighting
Iannucci & Howerton (p. 114) (Fig. 10-3)
Proper safelighting
No visible image is seen on the processed radiograph.
Improper safelighting
If an image of the coin and a fogged background appear on the processed radiograph

19. Processing Equipment Automatic processor test films
Prepare films by unwrapping two unexposed films and exposing one to light.
Process both films in the automatic processor.
Processing equipment must be meticulously maintained and monitored daily.
Temperature, levels of water, developer, and fixer solutions must be monitored.

20. Processing Equipment Functioning processor Nonfunctioning processor
The unexposed film appears clear and dry and the exposed film appears black and dry.
Nonfunctioning processor
If the unexposed film does not appear clear and dry and if the exposed film does not appear completely black and dry the processor is nonfunctioning.
This test should be performed with the automatic processor each day.

21. Processing Solutions Developer strength
Iannucci & Howerton (pp ) (Table 10-1)
Developer strength
Reference radiograph
Stepwedge radiographs
Normalizing device
Processing solutions should be replenished daily and changed every 3 to 4 weeks.

22. Reference Radiograph Processed under ideal conditions Prepare film.
Used to compare the film densities of radiographs that are processed daily
Prepare film.
Expose film using correct exposure factors.
Process film using fresh chemicals at recommended time and temperature.
View the reference radiograph and daily radiographs side by side on a viewbox.
Compare the densities on the reference radiograph with the densities on the daily radiographs.

23. Reference Radiograph Matched densities Unmatched densities
If densities seen on reference radiograph match daily radiographs, developer solution strength is adequate.
Unmatched densities
Daily radiographs are lighter than reference radiographs.
Developer solution is either weak or cold.
Daily radiographs are darker than reference radiographs.
Developer solution is either too concentrated or too warm.
Weakened or concentrated developer solution must be replaced.
If the developer solution is too warm or too cold the temperature must be adjusted.

24. Stepwedge Radiographs
A device of layered aluminum steps
Prepare film.
Use 20 films to create a supply for daily testing.
Expose the film.
Process one of the exposed films with fresh chemicals.
Store the remaining exposed 19 films.
Process one of the exposed stepwedge films each day.
View the standard radiograph and the daily radiograph side by side on a viewbox and compare densities.
A stepwedge is used to ensure that the developer solution is of the proper strength.

25. Stepwedge Radiographs
Iannucci & Howerton (pp ) (Figs. 8-6, 10-4, 10-5)
Matched densities
If densities match, the developer solution strength is adequate.
Unmatched densities
If the density on the daily radiograph differs by more than two steps from the standard, the developer solution is depleted.
Use the middle density see on the standard stepwedge radiograph for comparison.

26. Normalizing Device
Iannucci (p. 116)
Can be used to monitor developer strength and film density

27. Fixer Strength Prepare film. Check film for clearing.
As previously discussed, the fixer solution removes the unexposed silver halide crystals on the film.

28. Fixer Strength Fast clearing Slow clearing
Film clears in 2 minutes; fixer is of adequate strength.
Slow clearing
If the film does not completely clear in 3 to 4 minutes, the fixer solution is depleted.
If the fixer solution is depleted, it must be replaced before proceeding with processing.

29. Quality Administration Procedures
Iannucci & Howerton (p. 117)
Management of the quality assurance plan
Description of the plan
Assignment of duties
Monitoring schedule
Maintenance schedule
Record-keeping log
Plan for evaluation and revision
In-service training
A copy of the quality administration plan should be made available to all staff members.
Each staff member should participate in the quality assurance program.
Periodic in-service training of all staff members is recommended.

30. Operator Competence A nondiagnostic film must be retaken.
Iannucci & Howerton (p. 117)
A nondiagnostic film must be retaken.
Retakes expose the patient to additional radiation.
Repeated operator errors and errors requiring retakes should be recorded.
Continuing education courses and individualized instruction can be used to upgrade and improve the competence of the dental radiographer.