OKLAHOMA DENTAL RADIATION
PROTECTION AND SAFETY EXAM
Introduction
This examination reflects the standardized competency assessment approved by the Okla- homa Board
of Dentistry. It evaluates the candidate’s proficiency in radiation physics, bio- logical effects, protection
principles (ALARA), positioning techniques, and compliance with the Oklahoma Administrative Code
Title 195.
1. Which of the following is the primary purpose of the lead apron used during dental
radiography?
A. To protect the image receptor from scatter radiation
B. To protect the patient’s reproductive and blood-forming tissues from scatter ra- diation
C. To reduce the amount of primary radiation hitting the patient’s face
D. To satisfy Oklahoma insurance billing requirements
Rationale: Lead aprons and thyroid collars are designed to shield radiosensitive tissues (thy- roid,
gonads, bone marrow) from secondary/scatter radiation during exposure.
2. Under Oklahoma Administrative Code Title 195, a dental assistant must hold what prior to
performing radiologic procedures?
A. A high school diploma only
B. A valid dental assistant permit with a radiation safety credential
C. A letter of recommendation from a licensed dentist
D. A specialized degree in radiology
Rationale: Oklahoma law requires dental assistants to be permit holders and complete a Board-
approved radiation safety course and exam to legally take X-rays.
3. The term ”ALARA” stands for:
A. As Long As Radiographs are Accurate
B. As Low As Reasonably Achievable
C. All Levels of Advanced Radiation Alignment
D. Always Low And Relatively Accurate
Rationale: ALARA is the fundamental safety principle in radiology, ensuring that every pos- sible
precaution is taken to minimize radiation dose to both patients and operators.
4. Which exposure factor controls the penetrating power (quality) of the X-ray beam?
A. Milliamperage (mA)
1
, B. Exposure time
C. Kilovoltage peak (kVp)
D. The PID length
Rationale: kVp regulates the speed of electrons traveling from the cathode to the anode, which
determines the energy and penetrating ability of the resulting X-ray photons.
5. If a radiograph appears ”stretched out” or elongated, the error is likely caused by:
A. Excessive vertical angulation
B. Insufficient vertical angulation
C. Incorrect horizontal angulation
D. Using the paralleling technique
Rationale: Elongation occurs when the vertical angulation is too ”fiat” (insufficient), making the image
of the tooth appear longer than it is.
6. Which of the following cell types is MOST sensitive to radiation (Radiosensitive)?
A. Nerve cells
B. Muscle cells
C. Small lymphocytes (blood-forming cells)
D. Mature bone cells
Rationale: According to the Law of Bergonie and Tribondeau, cells that are rapidly dividing (highly
mitotic) and undifferentiated are the most radiosensitive.
7. What is the function of the aluminum filter in the X-ray tubehead?
A. To focus the beam into a small circle
B. To remove low-energy, long-wavelength X-rays from the beam
C. To increase the number of photons produced
D. To prevent the tubehead from overheating
Rationale: Aluminum filters remove the ”soft,” low-energy X-rays that lack enough power to penetrate
tissue and reach the sensor, thereby reducing unnecessary patient skin dose.
8. Which PID (Position Indicating Device) produces the least amount of scatter radiation for the
patient?
A. A short (8-inch) plastic pointed cone
B. A long (16-inch) rectangular PID
C. A long (16-inch) circular PID
D. A short (8-inch) circular PID
Rationale: Long, rectangular PIDs significantly reduce the volume of tissue irradiated and produce
less scatter radiation compared to short or circular devices.
9. Overlap of the interproximal contacts on a bitewing radiograph is caused by:
2
PROTECTION AND SAFETY EXAM
Introduction
This examination reflects the standardized competency assessment approved by the Okla- homa Board
of Dentistry. It evaluates the candidate’s proficiency in radiation physics, bio- logical effects, protection
principles (ALARA), positioning techniques, and compliance with the Oklahoma Administrative Code
Title 195.
1. Which of the following is the primary purpose of the lead apron used during dental
radiography?
A. To protect the image receptor from scatter radiation
B. To protect the patient’s reproductive and blood-forming tissues from scatter ra- diation
C. To reduce the amount of primary radiation hitting the patient’s face
D. To satisfy Oklahoma insurance billing requirements
Rationale: Lead aprons and thyroid collars are designed to shield radiosensitive tissues (thy- roid,
gonads, bone marrow) from secondary/scatter radiation during exposure.
2. Under Oklahoma Administrative Code Title 195, a dental assistant must hold what prior to
performing radiologic procedures?
A. A high school diploma only
B. A valid dental assistant permit with a radiation safety credential
C. A letter of recommendation from a licensed dentist
D. A specialized degree in radiology
Rationale: Oklahoma law requires dental assistants to be permit holders and complete a Board-
approved radiation safety course and exam to legally take X-rays.
3. The term ”ALARA” stands for:
A. As Long As Radiographs are Accurate
B. As Low As Reasonably Achievable
C. All Levels of Advanced Radiation Alignment
D. Always Low And Relatively Accurate
Rationale: ALARA is the fundamental safety principle in radiology, ensuring that every pos- sible
precaution is taken to minimize radiation dose to both patients and operators.
4. Which exposure factor controls the penetrating power (quality) of the X-ray beam?
A. Milliamperage (mA)
1
, B. Exposure time
C. Kilovoltage peak (kVp)
D. The PID length
Rationale: kVp regulates the speed of electrons traveling from the cathode to the anode, which
determines the energy and penetrating ability of the resulting X-ray photons.
5. If a radiograph appears ”stretched out” or elongated, the error is likely caused by:
A. Excessive vertical angulation
B. Insufficient vertical angulation
C. Incorrect horizontal angulation
D. Using the paralleling technique
Rationale: Elongation occurs when the vertical angulation is too ”fiat” (insufficient), making the image
of the tooth appear longer than it is.
6. Which of the following cell types is MOST sensitive to radiation (Radiosensitive)?
A. Nerve cells
B. Muscle cells
C. Small lymphocytes (blood-forming cells)
D. Mature bone cells
Rationale: According to the Law of Bergonie and Tribondeau, cells that are rapidly dividing (highly
mitotic) and undifferentiated are the most radiosensitive.
7. What is the function of the aluminum filter in the X-ray tubehead?
A. To focus the beam into a small circle
B. To remove low-energy, long-wavelength X-rays from the beam
C. To increase the number of photons produced
D. To prevent the tubehead from overheating
Rationale: Aluminum filters remove the ”soft,” low-energy X-rays that lack enough power to penetrate
tissue and reach the sensor, thereby reducing unnecessary patient skin dose.
8. Which PID (Position Indicating Device) produces the least amount of scatter radiation for the
patient?
A. A short (8-inch) plastic pointed cone
B. A long (16-inch) rectangular PID
C. A long (16-inch) circular PID
D. A short (8-inch) circular PID
Rationale: Long, rectangular PIDs significantly reduce the volume of tissue irradiated and produce
less scatter radiation compared to short or circular devices.
9. Overlap of the interproximal contacts on a bitewing radiograph is caused by:
2
