BDA DENTAL RADIOGRAPHY EXAM
QUESTIONS AND CORRECT ANSWERS
Question 1
What occurs during the Photo-electric effect when an X-ray photon collides with an
inner-shell electron?
Correct Answer
The photon's energy is completely absorbed, destabilizing the atom, which then
releases energy as heat and light.
Question 2
What practical infection control procedures should be followed during intra-oral
radiography?
Correct Answer
Use of gloves, masks, and sterilization of equipment.
Question 3
What quality criteria should be met for an upper standard occlusal projection?
Correct Answer
- Apices of upper incisor teeth clearly defined
- Minimal elongation/foreshortening
- Inclusion of unerupted canines
- First and second molars
- No geometrical distortion
- Appropriate contrast and density.
Question 4
What is the appearance of root/cervical caries on radiographs?
Correct Answer
They usually appear as radiolucent semicircles at the cervical margin.
Page 1 of 100
,Question 5
What is the importance of differentiating enamel, dentine, and pulp in radiographs?
Correct Answer
Differentiation allows for accurate diagnosis and assessment of dental conditions.
Question 6
How is Effective Dose calculated?
Correct Answer
Effective Dose = Equivalent Dose x Tissue Weighting Factor.
Question 7
What are the clinical indications for taking a bitewing radiograph?
Correct Answer
- Assessment of dental caries
- Monitoring progression of caries, Assessment of existing restorations
- Evaluation of periodontal status.
Question 8
What are the three main ways to reduce radiation dose to patients and staff?
Correct Answer
Clinical judgement, equipment, and radiographic technique.
Question 9
What is periapical cemento-osseous dysplasia?
Correct Answer
A lesion that initially appears as radiolucencies around the apices of teeth and later
calcifies to appear as opacities.
Page 2 of 100
,Question 10
How does the movement of the equipment affect the panoramic image?
Correct Answer
The film or sensor moves around the front of the patient's face while the X-ray
tubehead moves around the back, creating a tomographic layer.
Question 11
What does osteomyelitis look like on a radiograph?
Correct Answer
A poorly defined lucent area where the bone has been resorbed.
Question 12
What does ALARP stand for in the context of radiation exposure?
Correct Answer
As Low As Reasonably Practicable.
Question 13
What is the purpose of using a long focal spot distance (fsd) in the paralleling
technique?
Correct Answer
A long fsd (200mm) minimizes divergence of the X-ray beam, reducing image
magnification.
Question 14
What is the speed of intraoral fast film used in dental radiography?
Correct Answer
E/F speed.
Page 3 of 100
, Question 15
What adjustments should be made when taking panoramic radiographs of
edentulous patients?
Correct Answer
Do not use a bite-peg, rest the chin on the chin support, and center the canine
positioning light beam on the corner of the mouth.
Question 16
How does the dose from a modern panoramic X-ray compare to natural background
radiation?
Correct Answer
It gives the same dose as two days of natural background radiation.
Question 17
What is the purpose of a radiation risk assessment?
Correct Answer
To identify and mitigate potential hazards associated with the use of ionising
radiation.
Question 18
What can cause a film image to be too pale?
Correct Answer
Underexposure or underdevelopment.
Question 19
What is the importance of a quiet, darkened room when viewing radiographs?
Correct Answer
It enhances visibility and reduces distractions, allowing for better interpretation of
the radiographs.
Page 4 of 100
QUESTIONS AND CORRECT ANSWERS
Question 1
What occurs during the Photo-electric effect when an X-ray photon collides with an
inner-shell electron?
Correct Answer
The photon's energy is completely absorbed, destabilizing the atom, which then
releases energy as heat and light.
Question 2
What practical infection control procedures should be followed during intra-oral
radiography?
Correct Answer
Use of gloves, masks, and sterilization of equipment.
Question 3
What quality criteria should be met for an upper standard occlusal projection?
Correct Answer
- Apices of upper incisor teeth clearly defined
- Minimal elongation/foreshortening
- Inclusion of unerupted canines
- First and second molars
- No geometrical distortion
- Appropriate contrast and density.
Question 4
What is the appearance of root/cervical caries on radiographs?
Correct Answer
They usually appear as radiolucent semicircles at the cervical margin.
Page 1 of 100
,Question 5
What is the importance of differentiating enamel, dentine, and pulp in radiographs?
Correct Answer
Differentiation allows for accurate diagnosis and assessment of dental conditions.
Question 6
How is Effective Dose calculated?
Correct Answer
Effective Dose = Equivalent Dose x Tissue Weighting Factor.
Question 7
What are the clinical indications for taking a bitewing radiograph?
Correct Answer
- Assessment of dental caries
- Monitoring progression of caries, Assessment of existing restorations
- Evaluation of periodontal status.
Question 8
What are the three main ways to reduce radiation dose to patients and staff?
Correct Answer
Clinical judgement, equipment, and radiographic technique.
Question 9
What is periapical cemento-osseous dysplasia?
Correct Answer
A lesion that initially appears as radiolucencies around the apices of teeth and later
calcifies to appear as opacities.
Page 2 of 100
,Question 10
How does the movement of the equipment affect the panoramic image?
Correct Answer
The film or sensor moves around the front of the patient's face while the X-ray
tubehead moves around the back, creating a tomographic layer.
Question 11
What does osteomyelitis look like on a radiograph?
Correct Answer
A poorly defined lucent area where the bone has been resorbed.
Question 12
What does ALARP stand for in the context of radiation exposure?
Correct Answer
As Low As Reasonably Practicable.
Question 13
What is the purpose of using a long focal spot distance (fsd) in the paralleling
technique?
Correct Answer
A long fsd (200mm) minimizes divergence of the X-ray beam, reducing image
magnification.
Question 14
What is the speed of intraoral fast film used in dental radiography?
Correct Answer
E/F speed.
Page 3 of 100
, Question 15
What adjustments should be made when taking panoramic radiographs of
edentulous patients?
Correct Answer
Do not use a bite-peg, rest the chin on the chin support, and center the canine
positioning light beam on the corner of the mouth.
Question 16
How does the dose from a modern panoramic X-ray compare to natural background
radiation?
Correct Answer
It gives the same dose as two days of natural background radiation.
Question 17
What is the purpose of a radiation risk assessment?
Correct Answer
To identify and mitigate potential hazards associated with the use of ionising
radiation.
Question 18
What can cause a film image to be too pale?
Correct Answer
Underexposure or underdevelopment.
Question 19
What is the importance of a quiet, darkened room when viewing radiographs?
Correct Answer
It enhances visibility and reduces distractions, allowing for better interpretation of
the radiographs.
Page 4 of 100
