NATIONAL BOARD DENTAL HYGIENE
EXAMINATION PRACTICE REVIEW 2026
TESTED QUESTIONS
◉ From the following list, select two structures that appear
radiolucent on a radiographic image. Answer: Lateral or canine
fossa, Nutrient canals
◉ The indirect theory of radiation injury suggests that cell damage
occurs when ionizing radiation hits critical areas within the cell. The
direct theory of radiation injury suggests that x-ray photons are
absorbed within the cell and cause the formation of toxins that in
turn damage the cell.. Answer: Both statements are false
◉ Which statement BEST describes the relationship of the image
receptor and the tooth in the paralleling technique?. Answer: * The
image receptor is parallel to the long axis of the tooth.
* The central ray of the x-ray beam is directed perpendicular to the
receptor and the long axis of the tooth.
◉ All of the following are examples of radiosensitive cells EXCEPT
one. Which one is the EXCEPTION?. Answer: Older, mature cells
,◉ Identify the structure to which the arrows are pointing in the
image shown.. Answer: Zygoma
◉ Anode. Answer: Positive electrode
◉ Cathode. Answer: Negative electrode
◉ Kilovoltage. Answer: controls the force of the electrons
◉ Milliamperage. Answer: controls the number of electrons
◉ Molybdenum. Answer: Narrows the beam and controls the
direction of the beam
◉ Tungsten filament. Answer: produces electrons
◉ Tungsten target. Answer: Spot where the electrons are converted
into x-ray photons
◉ Thermionic emission. Answer: Release of electrons from the
tungsten filament when the electrical current passes through it and
heats the filament
, ◉ Step-down transformer. Answer: decreases voltage
◉ Collimator. Answer: Restricts the size and shape of the x-ray beam
to reduce patient exposure
◉ The tubehead is a component of the x-ray machine that helps limit
radiation to the patient in all of the following functions EXCEPT one.
Which one is the EXCEPTION?. Answer: Production of both long-
wavelength and short-wavelength x-rays
◉ In the image shown, which permanent tooth is unerupted?.
Answer: #4
◉ A periapical image of the maxillary right molar area is needed, but
patient has a shallow palate, and the first image taken misses the
apices of the teeth. To correct this error, using the paralleling
technique, an acceptable image can be obtained by moving the
position indicating device (PID) in a. Answer: positive 20-degree
difference in the vertical angulation.
◉ When taking a premolar bitewing image, which error in the
position of the PID is seen in the photograph shown?. Answer:
Greater negative vertical angulation than required
◉ Which factor affects contrast?. Answer: kVp
EXAMINATION PRACTICE REVIEW 2026
TESTED QUESTIONS
◉ From the following list, select two structures that appear
radiolucent on a radiographic image. Answer: Lateral or canine
fossa, Nutrient canals
◉ The indirect theory of radiation injury suggests that cell damage
occurs when ionizing radiation hits critical areas within the cell. The
direct theory of radiation injury suggests that x-ray photons are
absorbed within the cell and cause the formation of toxins that in
turn damage the cell.. Answer: Both statements are false
◉ Which statement BEST describes the relationship of the image
receptor and the tooth in the paralleling technique?. Answer: * The
image receptor is parallel to the long axis of the tooth.
* The central ray of the x-ray beam is directed perpendicular to the
receptor and the long axis of the tooth.
◉ All of the following are examples of radiosensitive cells EXCEPT
one. Which one is the EXCEPTION?. Answer: Older, mature cells
,◉ Identify the structure to which the arrows are pointing in the
image shown.. Answer: Zygoma
◉ Anode. Answer: Positive electrode
◉ Cathode. Answer: Negative electrode
◉ Kilovoltage. Answer: controls the force of the electrons
◉ Milliamperage. Answer: controls the number of electrons
◉ Molybdenum. Answer: Narrows the beam and controls the
direction of the beam
◉ Tungsten filament. Answer: produces electrons
◉ Tungsten target. Answer: Spot where the electrons are converted
into x-ray photons
◉ Thermionic emission. Answer: Release of electrons from the
tungsten filament when the electrical current passes through it and
heats the filament
, ◉ Step-down transformer. Answer: decreases voltage
◉ Collimator. Answer: Restricts the size and shape of the x-ray beam
to reduce patient exposure
◉ The tubehead is a component of the x-ray machine that helps limit
radiation to the patient in all of the following functions EXCEPT one.
Which one is the EXCEPTION?. Answer: Production of both long-
wavelength and short-wavelength x-rays
◉ In the image shown, which permanent tooth is unerupted?.
Answer: #4
◉ A periapical image of the maxillary right molar area is needed, but
patient has a shallow palate, and the first image taken misses the
apices of the teeth. To correct this error, using the paralleling
technique, an acceptable image can be obtained by moving the
position indicating device (PID) in a. Answer: positive 20-degree
difference in the vertical angulation.
◉ When taking a premolar bitewing image, which error in the
position of the PID is seen in the photograph shown?. Answer:
Greater negative vertical angulation than required
◉ Which factor affects contrast?. Answer: kVp
