Study guide for chapters 10 and 11
What tests can you use to check Developer strength? Know all of the tests. Pg 107
An easy way to check the strength of the developer solution is to compare film densities to a standard. One of the following test can be used: > Reference radiograph >Stepwedge radiography > Normalizing device
Information found on dental images
Missing teeth, extra teeth, impacted teeth, dental caries, periodontal disease, tooth abnormalities, retained roots, cysts and tumors.
According to the textbook, what is the MOST important use of dental images?
One of the most important uses of dental images is for detection of diseases, lesions, and conditions of the teeth and bones that cannot be identified by clinical examination alone.
When should you avoid taking retake radiographs?
Whenever the dental radiographer performs imaging procedures on the patients, the lowest possible level of x-radiation must be used. Retakes resulting in unnecessary patient exposure must be avoided at all times.
Where is the best place to view the radiograph you used for the film screen contact test?
on a viewbox in a dimly lit room at a distance of 6 ft
Please keep in mind that all of the following MUST be fresh before creating a Reference radiograph.
• Film • Developer solution • Fixer solution
For dental xray machines check:
• X-ray output • Kilovoltage (kV) calibration • Half-value layer (HVL) • Timer • Milliamperage (mA) • Collimation • Beam alignment • Tubehead stability
Where is the wire mesh test object placed for the film screen contact test?
(Pg 105) Place a wire mesh test object on top of the loaded cassette.
Describe how you would conduct a Light-leak test.
1. Close the darkroom door, and turn off all the lights including the safelight. 2. Once your eyes become accustomed to the darkness, observe the areas around the door, the seams of the walls and ceilings, the vent area, and the keyhole for the light leaks. PG.106
List examples of various Quality Control tests. Page 110. Please know how they are performed. *Also BOX 10-2 Page 105; List for Dental X-ray Machines (Review This)
1. X-ray machines- test for minor malfunctions, output variations, collimation problems, tubehead drift, timing errors, and inaccurate kilovoltage and milliamperage readings performed yearly 2. X-ray film- fresh film test is used to determine whether dental x-ray film is fresh and has been properly stored and protected. Perform each time a new box of film is opened. 3. Screens and cassettes- Cassettes should be examined for adequate closure, light leaks, and warping. The screen-film contact test is used to determine the adequacy of contact. Performed monthly. More frequently if the screens and cassettes are used often. 4. Darkroom lighting- The light leak test can be used to evaluate the darkroom for light leaks and is performed monthly. The safelighting test can be used to check for proper safelighting conditions and is performed every 6 months. 5. Processing equipment- Processing equipment must be carefully maintained and monitored daily for potential problems. With manual processing techniques, the thermometer and timer must be accurate, and the temperature and level of the water bath, developer, and fixer solutions must be checked. The automatic processor test can be used to check the functioning of the automatic processor. Performed daily. 6. Processing solutions- The developer strength can be monitored by a reference radiograph, stepwedge radiographs, or a normalizing device. The fixer solution can be checked by performing a clearing test. Performed daily
Define Reference Radiograph. What is it used to evaluate?
A radiograph processed under ideal conditions and then used to compare the film densities of radiographs that are processed daily. An intraoral film prepared in this manner yields a high-quality image that can be used as a comparative radiograph. (Page 107)
Define Film-screen contact test and how it is carried out. What is being tested? Page 105 BOX
Checks for adequate contact between the intensifying screens and film Steps: 1. Load cassette. Insert one film between the screens in the cassette 2. Place test object. Place a wire mesh test object on top of the loaded cassette. 3. Position the PID. Position PID using a 40-inch target-receptor distance, direct the central ray perpendicular to the cassette. 4. Expose the cassette. Expose the cassette using 10 mA, 70 kV, and 0.25 seconds. 5. Process the film. Process the exposed film 6. View. Check the film on a viewbox in a dimly lit room at a distance of 6 ft. Adequate: wire mesh exhibits uniform density, good contact Inadequate: wire mesh exhibits varying densities, poor contact. Poor screen contact areas appear darker than good contact areas. Must replace cassette Target-film distance of the PID when performing the film screen contact test Position the position-indicating device (PID) using a 40-inch target-receptor distance while directing the central ray perpendicular to the cassette.
Importance of dental images
Dental images are essential for diagnostic purposes. Images enable the dental professional to identify many conditions that may otherwise go undetected and to see many conditions that are not apparent clinically. With the use of dental images, the dental professional gains a great deal of information about teeth and supporting structures
List the ways dental images can be used for? Several ways noted in the textbook.
Detection of disease, lesions, and conditions of the teeth and bones that cannot be identified by clinical examination alone;confirming suspected diseases and for assisting in the localization of lesions and foreign objects; provide essential info during routine dental treatment; essential component of the patient record (page 113)
How frequently should the panoramic cassette intensifying screens be cleaned?
Extraoral intensifying screens used within a cassette holder should be periodically examined for the presence of any dirt and scratches. Screens should be cleaned on a monthly basis with commercially available cleaners recommended by the screen manufacturer. After the screen is cleaned an antistatic solution should be applied.
If densities on a test film are lighter than the reference film, what does this mean? Page 108 BOX
If they are lighter, the developer solution is either weak or cold. If they are darker, the developer solution is too concentrated or too warm.
List all of the people who can be a dental radiographer in the dental office.
In a typical practice, the dental radiographer is a dental auxiliary, either a dental hygienist or dental assistant. The dental radiographer must have sufficient knowledge and technical skills to perform dental imaging procedures and must have a thorough understanding of his or her responsibilities and professional goals. (Page 114)
Definition of a dental image
Is a two-dimensional representation of a three-dimensional object produced by the passage of x-rays through teeth and supporting structures.
How frequently do you monitor digital imaging equipment in the dental office?
It is recommended to perform a backup of the digital data on the computer on a daily basis especially in offices with high patient volume. ALong with annual testing for the calibration of the imaging equipment, the receptors (direct or indirect imaging) also requires periodic examination for scratches, bending, and general wear and tear.
In Chapter 11, list the uses of dental images
One of the most important uses of dental images is for detection of diseases, lesions, and conditions of the teeth and bones that cannot be identified by clinical examination alone. Dental images are also used for confirming suspected diseases and for assisting in the localization of lesions and foreign objects. Can be used to examine the status of teeth and bone during growth and development. Dental images provide the practitioner with baseline information about the patient. Each image serves to document the patient's condition at a specific time.
List the duties and responsibilities of the dental auxiliary member.
Positioning and exposure of dental x-ray imaging receptors; Processing of dental x-ray films; Data retrieval of digital images; Mounting and identification of dental images; Education of patients about dental imaging; Maintenance of darkroom and processing equipment; Implementation and monitoring of quality control tests; Ordering of dental x-ray equipment and related supplies.
What is your responsibility as a dental radiographer? Look in the book for descriptions.
Positioning and exposure of dental x-ray imaging receptors; processing of dental x-ray films; data retrieval of digital images; mounting and identification of dental images; education of patients about dental imaging; maintenance of darkroom and processing equipment; implementation and monitoring of quality control tests; ordering of dental x-ray equipment and related supplies (page 114)
Define Quality Assurance Monitoring. Note examples. Pg 104
Quality assurance refers to special procedures that are used to ensure the production of high quality diagnostic images. A quality assurance plan includes both quality control tests and quality administration procedures. Quality assurance plans include equipment use in dental imaging, including the x ray machine, sensors,and computer. Other examples include the use of logs to record retakes and continuing education courses for personnel.
Define Quality Controls. Note examples.
Quality control tests are specific tests that are used to maintain and monitor dental x-ray units, supplies, film processing, and digital imaging equipment. To avoid excess exposure of patients and personnel, the dental radiographer must have a clear understanding of the quality control procedures. Examples include inspection of x ray machines, proper storage of film, examination of extraoral intensifying screens, using the viewbox, monitoring processing solutions, checking darkroom for light-tightness, stepwedge radiographs, etc.
What do you do if you notice your intensifying screen is scratched?
Screens that have visible scratches or visible wear should be replaced.
Automatic Processor Test: describe how to do and results you may have and what those results mean if the machine is functioning properly or improperly. What do the films look like?
Steps: 1. Prepare the films. Unwrap two unexposed films; expose one to light. 2. Process both films in the automatic processor. Results: Functioning processor- unexposed film appears clear and dry, & film exposed to light appears black and dry. Processor is functioning good Nonfunctioning processor- unexposed film does not appear clear and dry, & exposed film does not appear completely black and dry. Processing solutions and dryer temperature must be checked. Corrections must be made before proceeding
Define Coin Test, describe how to perform and results.
Steps: 1. Prepare the darkroom. Turn off all lights in the darkroom, including the safelight. 2. Prepare the film. Unwrap one unexposed film and place on a flat surface 4 feet from the safelight and place coin on top of the film. 3. Turn on the safelight. Allow the film and coin to be exposed to the safelight for 3-4 minutes. 4. Process the film. Remove the coin, and process the film. Results: 1. Proper safelighting. If no visible image is seen on the processed film the safelight is correct. Proceed with film processing. 2. Improper safelighting. If the image of the coin and a fogged background appear on the processed film, the safelight is not safe to use. Safelighting problems must be corrected before proceeding with film processing.
Fresh film test: Steps and results.
Steps: 1. Prepare the film. Unwrap one unexposed film from a newly opened box. 2. Process the film. Use fresh chemicals to process the unexposed film. Results: Fresh film. If the processed film appears clear with a slight blue tint, the film is fresh and has been properly stored and protected. Proceed with the use of this film. Fogged film. Film that has expired, has been improperly stored, or has been exposed to radiation appear fogged. If the film is fogged, it should not be used.
Describe the Viewbox and qualities it needs to be functioning properly. pg 105
The viewbox, or illuminator, is a light source that is used to view processed films. A working viewbox is a necessary piece or equipment for the interpretation of dental images. The view box contains fluorescent light bulbs that emit light through an opaque plastic or plexiglas front.The viewbox should emit a uniform and subdued light when it is functioning properly. A photographic light meter can be used to determine proper viewing brightness.
Operator protection
To avoid occupational exposure to x-radiation, the dental radiographer must always avoid the primary beam and maintain the adequate distance, proper position, and proper shielding from x-rays during procedure. A radiation monitoring badge can be used to measure the amount of x-radiation received by the dental radiographer and to identify any excessive occupational exposure.
What do you use to perform a safelighting test? Where do you perform this test? Location in the dental office? Pg 106
To perform a safelight test, you must use a coin placed on unexposed film under safelight. You perform this test in the darkroom. Developed film showing outline of coin indicates that the safelight intensity is too great and is not safe. If no visible image is seen on the processed film, the safelight is correct.
What are Stepwedge radiographs and how are they used to check for Quality Assurance? List the steps noted in the textbook and how the test is carried out. pg 107-8
When a step wedge (layered aluminum steps) is placed on top of a film and then exposed to x rays, the different steps absorb varying amounts of x rays. When processed, different film densities are seen on the dental radiograph as a result of the step wedge. If the MIDDLE density seen on the standard step wedge matches the density seen on the daily radiograph, the developer solution strength is adequate...If it differs from the standard radiograph by more than two steps, the deeper solution is depleted and must be changed. STEPS: 1. Prepare the films (20 fresh films). Place an aluminum step wedge on top of one film. 2. Expose the film. Repeat with remaining films using the same step wedge, target receptor distance, and exposure factors. 3. Using fresh chemicals, process only one of the exposed films. This processed radiograph is known as the standard step wedge radiograph. 4. Store the remaining 19 exposed films in a cool, dry area protected from x radiation. 5. Each day, after that chemicals have been replenished, process one of the exposed step wedge films. This film is known as the daily radiograph. 6. View The standard radiograph and the daily radiography side by side on a view box. Compare the densities.
Prior to using the Developer solution each day, you will compare the reference radiograph to test a film that you develop to check to see if the Developer chemicals are depleted. After developing the test film, what are you comparing when you look at the test film with the reference film? Page 108 BOXES.
You are comparing the densities between the reference radiograph and test radiograph to see if the densities match If the densities seen on the daily radiographs appear lighter than on the reference radiograph, the developer solution is either weak or cold If the densities seen on the daily radiographs appear darker than on the reference radiograph, the developer solution is either too concentrated or too warm