Certification Examination Practice

Illinois Radiology Dental Assistant Certification Examination Practice Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

• What is the primary purpose of dental radiography?
• To replace clinical examination
• To increase insurance reimbursement
• To diagnose conditions not visible clinically
• To forecast patient tooth loss

Rationale: Radiographs supplement the clinical exam and help identify

conditions that cannot be seen directly, such as caries between teeth or bone loss.

• Which type of radiation causes ionization? 1 / 4

• Radio waves
• Visible light
• X-rays
• Sound waves

Rationale: X-rays are ionizing radiation capable of removing electrons from

atoms.

• The component of the X-ray tubehead that restricts the size of the beam

is the:

A. PID

• Transformer
• Collimator
• Tube window

Rationale: The collimator narrows the beam and reduces patient exposure.

• What does kVp control in dental radiography?
• Quantity of electrons
• Quality (penetrating power) of the beam
• Focal spot size
• Film speed

Rationale: Higher kVp increases beam energy and penetrability.

• Which exposure factor controls the number of X-rays produced?
• kVp
• mA 2 / 4

• Filtration
• Collimation

Rationale: mA regulates the amount of current and determines X-ray

quantity.

6. Increasing exposure time affects the radiograph by:

• Decreasing density
• Increasing density
• Increasing contrast
• Removing scatter

Rationale: Longer exposure produces more X-rays, making the image

darker.

• Which tissues are MOST sensitive to ionizing radiation?
• Muscle
• Bone marrow
• Nerve tissue
• Mature bone

Rationale: Rapidly dividing cells like bone marrow are highly

radiosensitive.

• What is the maximum permissible dose (MPD) for occupationally

exposed workers per year?

• 1 mSv
• 50 mSv 3 / 4

• 100 mSv
• 5 mSv

Rationale: OSHA and NCRP guidelines set occupational MPD at 50

mSv/year.

• What device measures accumulated radiation exposure?
• Thermostat
• Geiger counter
• Dosimeter badge
• Beam restrictor

Rationale: A dosimeter tracks long-term radiation exposure for workers.

10. The ALARA principle means:

• Avoid radiographs completely
• Use lowest dose reasonably achievable
• Repeat images freely
• Always use handheld units

Rationale: ALARA minimizes exposure while obtaining diagnostic images.

11. The part of the X-ray tube where electrons are generated is the:

• Anode
• Cathode
• Filament transformer
• Oil-filled housing
• / 4