ADAP Radiography 3 — Questions and Answers
Question 1: What is the ALARA principle in dental radiography?
- Always Limit All Radiation Areas
- As Low As Reasonably Achievable (Correct answer)
- Apply Leaded Apron for Radiation Attenuation
- Automatic Low-dose Acquisition Radiograph Adjustment
Correct answer: As Low As Reasonably Achievable
ALARA stands for As Low As Reasonably Achievable and guides practitioners to minimize radiation exposure while still obtaining diagnostic-quality images.
Question 2: Which of the following is a characteristic of a digital radiographic sensor compared to traditional film?
- Requires chemical processing with developer and fixer
- Produces higher radiation exposure to achieve the same image quality
- Provides an immediate image on a computer monitor (Correct answer)
- Has a larger receptor surface than conventional film
Correct answer: Provides an immediate image on a computer monitor
Digital sensors display the radiographic image almost instantly on a computer monitor, eliminating darkroom processing time.
Question 3: What is the function of the fixer solution in traditional film processing?
- Converts exposed silver halide crystals to black metallic silver
- Removes unexposed silver halide crystals and hardens the emulsion (Correct answer)
- Clears the film of developer chemical residue only
- Intensifies the latent image on the film
Correct answer: Removes unexposed silver halide crystals and hardens the emulsion
Fixer removes unexposed and undeveloped silver halide crystals from the emulsion and hardens the gelatin, making the image permanent and stable.
Question 4: Which radiographic error results from the X-ray beam not being centered on the receptor, cutting off part of the image?
- Foreshortening
- Cone cutting (Correct answer)
- Overlapping
- Blurring
Correct answer: Cone cutting
Cone cutting occurs when the PID (position-indicating device) is misaligned and the X-ray beam misses part of the receptor, leaving a clear unexposed area on the processed image.
Question 5: What does milliamperage (mA) control in an X-ray unit?
- The energy level of X-ray photons produced
- The quantity (number) of X-rays produced per unit time (Correct answer)
- The contrast of the final radiographic image
- The penetrating quality of the X-ray beam
Correct answer: The quantity (number) of X-rays produced per unit time
Milliamperage controls the amount of current flowing through the X-ray tube filament, which determines the number of electrons available to produce X-rays (quantity).
Question 6: A radiograph appears too light (low density). Which adjustment would most directly correct this?
- Decrease the kVp setting
- Decrease the exposure time
- Increase the mA or exposure time (Correct answer)
- Move the PID farther from the patient
Correct answer: Increase the mA or exposure time
Increasing mA or exposure time increases the number of X-ray photons reaching the receptor, resulting in greater density and a darker image.
Question 7: What is the primary purpose of the thyroid collar used during dental radiography?
- Protect the patient's eyes from X-ray scatter
- Shield the thyroid gland from ionizing radiation (Correct answer)
- Prevent patient movement during exposure
- Reduce backscatter radiation to the operator
Correct answer: Shield the thyroid gland from ionizing radiation
The thyroid collar is a lead shield attached to or separate from the lead apron, specifically designed to protect the highly radiosensitive thyroid gland.
ADAP Radiography 3
What is the ALARA principle in dental radiography?