Dental Radiology Final Exam Review
Questions with Complete Solutions
What is the primary purpose of using the paralleling technique in dental radiography?
✔✔The paralleling technique minimizes distortion and provides accurate, high-quality images
by positioning the film parallel to the long axis of the tooth.
What is the ideal positioning for the X-ray tube in relation to the film and the patient?
✔✔The X-ray tube should be positioned perpendicular to the film and the tooth being
radiographed to avoid distortion.
How can you reduce patient radiation exposure during dental radiography?
✔✔To reduce exposure, use the lowest possible settings (mA and kVp), limit the number of
radiographs, and employ proper positioning and technique.
What is the function of a manual developer tank in film processing?
✔✔The manual developer tank holds the developer solution, which chemically converts exposed
silver halide crystals into a visible image on the film.
1
,What should be done if a patient has a gag reflex during radiographic procedures?
✔✔If a patient has a gag reflex, use techniques such as distraction, shallow insertion, and shorter
exposure times to minimize discomfort.
Why is it important to position the central ray correctly during a radiographic exposure?
✔✔Proper central ray positioning ensures that the image is clear and accurate, avoiding
distortion and allowing for proper diagnosis.
What is the purpose of the radiograph's density?
✔✔The density of a radiograph refers to the overall blackness or darkness of the image, which is
determined by the amount of X-rays that pass through the tissues.
What is a panoramic radiograph primarily used for?
✔✔A panoramic radiograph is used to capture a wide view of the upper and lower jaws, teeth,
and surrounding structures, aiding in diagnosis and treatment planning.
What is the difference between a direct and an indirect digital radiograph system?
✔✔A direct digital system uses a sensor to capture the image, while an indirect system uses a
phosphor plate that is read by a scanner to produce the image.
2
,How do you handle a dental X-ray film to prevent contamination?
✔✔To prevent contamination, handle the film by the edges, avoiding contact with the emulsion,
and store it in a clean, dry environment.
What is the role of the lead foil inside the film packet?
✔✔The lead foil helps to prevent backscatter radiation from reaching the film, which would
otherwise degrade the image quality.
How does the X-ray beam affect the radiograph’s contrast?
✔✔The X-ray beam's energy (kVp) affects the contrast by determining the level of penetration
through tissues, with higher kVp resulting in lower contrast and better visibility of details.
What are the common causes of dental radiograph artifacts?
✔✔Artifacts can be caused by improper handling, exposure to light, static electricity, patient
movement, or incorrect processing techniques.
Why is the use of a positioning device important in dental radiography?
3
, ✔✔A positioning device ensures accurate alignment of the X-ray film or sensor with the teeth,
reducing the risk of image distortion and the need for retakes.
What should be done if a radiograph shows overlapping images?
✔✔Overlapping can be avoided by ensuring the proper horizontal angulation of the X-ray beam
during exposure to prevent teeth from superimposing.
What is the purpose of using a phosphor plate in digital radiography?
✔✔A phosphor plate stores the X-ray energy and later releases it as a visible image when
scanned by a reader.
What is the proper procedure for developing dental X-ray films manually?
✔✔The procedure involves immersing the film in the developer solution for a specific time,
followed by rinsing, fixing the film in the fixer solution, and washing to remove chemicals.
What should be done if a film shows signs of underexposure?
✔✔If the film appears too light, increase the exposure time or adjust the settings to ensure proper
exposure.
4
Questions with Complete Solutions
What is the primary purpose of using the paralleling technique in dental radiography?
✔✔The paralleling technique minimizes distortion and provides accurate, high-quality images
by positioning the film parallel to the long axis of the tooth.
What is the ideal positioning for the X-ray tube in relation to the film and the patient?
✔✔The X-ray tube should be positioned perpendicular to the film and the tooth being
radiographed to avoid distortion.
How can you reduce patient radiation exposure during dental radiography?
✔✔To reduce exposure, use the lowest possible settings (mA and kVp), limit the number of
radiographs, and employ proper positioning and technique.
What is the function of a manual developer tank in film processing?
✔✔The manual developer tank holds the developer solution, which chemically converts exposed
silver halide crystals into a visible image on the film.
1
,What should be done if a patient has a gag reflex during radiographic procedures?
✔✔If a patient has a gag reflex, use techniques such as distraction, shallow insertion, and shorter
exposure times to minimize discomfort.
Why is it important to position the central ray correctly during a radiographic exposure?
✔✔Proper central ray positioning ensures that the image is clear and accurate, avoiding
distortion and allowing for proper diagnosis.
What is the purpose of the radiograph's density?
✔✔The density of a radiograph refers to the overall blackness or darkness of the image, which is
determined by the amount of X-rays that pass through the tissues.
What is a panoramic radiograph primarily used for?
✔✔A panoramic radiograph is used to capture a wide view of the upper and lower jaws, teeth,
and surrounding structures, aiding in diagnosis and treatment planning.
What is the difference between a direct and an indirect digital radiograph system?
✔✔A direct digital system uses a sensor to capture the image, while an indirect system uses a
phosphor plate that is read by a scanner to produce the image.
2
,How do you handle a dental X-ray film to prevent contamination?
✔✔To prevent contamination, handle the film by the edges, avoiding contact with the emulsion,
and store it in a clean, dry environment.
What is the role of the lead foil inside the film packet?
✔✔The lead foil helps to prevent backscatter radiation from reaching the film, which would
otherwise degrade the image quality.
How does the X-ray beam affect the radiograph’s contrast?
✔✔The X-ray beam's energy (kVp) affects the contrast by determining the level of penetration
through tissues, with higher kVp resulting in lower contrast and better visibility of details.
What are the common causes of dental radiograph artifacts?
✔✔Artifacts can be caused by improper handling, exposure to light, static electricity, patient
movement, or incorrect processing techniques.
Why is the use of a positioning device important in dental radiography?
3
, ✔✔A positioning device ensures accurate alignment of the X-ray film or sensor with the teeth,
reducing the risk of image distortion and the need for retakes.
What should be done if a radiograph shows overlapping images?
✔✔Overlapping can be avoided by ensuring the proper horizontal angulation of the X-ray beam
during exposure to prevent teeth from superimposing.
What is the purpose of using a phosphor plate in digital radiography?
✔✔A phosphor plate stores the X-ray energy and later releases it as a visible image when
scanned by a reader.
What is the proper procedure for developing dental X-ray films manually?
✔✔The procedure involves immersing the film in the developer solution for a specific time,
followed by rinsing, fixing the film in the fixer solution, and washing to remove chemicals.
What should be done if a film shows signs of underexposure?
✔✔If the film appears too light, increase the exposure time or adjust the settings to ensure proper
exposure.
4
