TCDHA RAD Midterm 1 Dental
Radiography ACTUAL EXAM 2026/2027:
100% Verified Questions & Correct
Answers
Question 1:
The target material in a dental x-ray tube is typically composed of:
A. Copper
B. Tungsten
C. Aluminum
D. Lead
Correct Answer: B
Rationale: Tungsten (atomic number 74) is used as the target anode due to its high melting point
(3,410°C) and efficient x-ray production via bremsstrahlung and characteristic radiation.
,Question 2:
The ALARA principle in dental radiography stands for:
A. As Low As Reasonably Achievable
B. As Long As Radiation Avoided
C. All Levels Are Radiation Acceptable
D. Always Limit All Radiation Amounts
Correct Answer: A
Rationale: ALARA (As Low As Reasonably Achievable) is the fundamental radiation safety principle
requiring doses to be minimized while maintaining diagnostic quality.
Question 3:
The kilovoltage peak (kVp) setting primarily controls:
A. The quantity (number) of x-rays produced
B. The quality (penetrating ability) of x-rays produced
C. The exposure time
D. The film processing speed
,Correct Answer: B
Rationale: kVp determines the energy/wavelength of x-rays; higher kVp = shorter wavelength =
greater penetration (quality), while mA controls quantity.
Question 4:
The paralleling technique for periapical radiographs requires the film/sensor to be placed:
A. At any angle to the tooth
B. Parallel to the long axis of the tooth
C. Perpendicular to the long axis of the tooth
D. Bisecting the angle between tooth and film
Correct Answer: B
Rationale: The paralleling technique positions the film/sensor parallel to the long axis of the tooth,
with the central ray perpendicular to both, minimizing distortion.
Question 5:
The maximum permissible dose (MPD) for a dental radiographer (occupational exposure) per year
is:
, A. 0.5 rem (5 mSv)
B. 5 rem (50 mSv)
C. 50 rem (500 mSv)
D. 500 rem (5,000 mSv)
Correct Answer: B
Rationale: NCRP Report No. 116: annual occupational dose limit is 5 rem (50 mSv) whole-body
effective dose; 50 rem (500 mSv) to extremities.
Question 6:
The bisecting angle technique is indicated when:
A. The paralleling technique can be used
B. The film cannot be placed parallel to the tooth long axis due to anatomy
C. Extraoral radiographs are needed
D. Digital sensors are unavailable
Correct Answer: B
Rationale: The bisecting technique is used when anatomic constraints (shallow palate, tori, shallow
floor of mouth) prevent parallel film placement.
Radiography ACTUAL EXAM 2026/2027:
100% Verified Questions & Correct
Answers
Question 1:
The target material in a dental x-ray tube is typically composed of:
A. Copper
B. Tungsten
C. Aluminum
D. Lead
Correct Answer: B
Rationale: Tungsten (atomic number 74) is used as the target anode due to its high melting point
(3,410°C) and efficient x-ray production via bremsstrahlung and characteristic radiation.
,Question 2:
The ALARA principle in dental radiography stands for:
A. As Low As Reasonably Achievable
B. As Long As Radiation Avoided
C. All Levels Are Radiation Acceptable
D. Always Limit All Radiation Amounts
Correct Answer: A
Rationale: ALARA (As Low As Reasonably Achievable) is the fundamental radiation safety principle
requiring doses to be minimized while maintaining diagnostic quality.
Question 3:
The kilovoltage peak (kVp) setting primarily controls:
A. The quantity (number) of x-rays produced
B. The quality (penetrating ability) of x-rays produced
C. The exposure time
D. The film processing speed
,Correct Answer: B
Rationale: kVp determines the energy/wavelength of x-rays; higher kVp = shorter wavelength =
greater penetration (quality), while mA controls quantity.
Question 4:
The paralleling technique for periapical radiographs requires the film/sensor to be placed:
A. At any angle to the tooth
B. Parallel to the long axis of the tooth
C. Perpendicular to the long axis of the tooth
D. Bisecting the angle between tooth and film
Correct Answer: B
Rationale: The paralleling technique positions the film/sensor parallel to the long axis of the tooth,
with the central ray perpendicular to both, minimizing distortion.
Question 5:
The maximum permissible dose (MPD) for a dental radiographer (occupational exposure) per year
is:
, A. 0.5 rem (5 mSv)
B. 5 rem (50 mSv)
C. 50 rem (500 mSv)
D. 500 rem (5,000 mSv)
Correct Answer: B
Rationale: NCRP Report No. 116: annual occupational dose limit is 5 rem (50 mSv) whole-body
effective dose; 50 rem (500 mSv) to extremities.
Question 6:
The bisecting angle technique is indicated when:
A. The paralleling technique can be used
B. The film cannot be placed parallel to the tooth long axis due to anatomy
C. Extraoral radiographs are needed
D. Digital sensors are unavailable
Correct Answer: B
Rationale: The bisecting technique is used when anatomic constraints (shallow palate, tori, shallow
floor of mouth) prevent parallel film placement.
