BDA RADIOGRAPHY AND RADIOLOGY
QUESTIONS 100 COMPLETE DENTAL
PRACTICE TEST BANK WITH ANSWERS
BOLDED and COMPREHENSIVE
RATIONALES UPDATED 2026
BDA Dental Radiography and Radiology Practice
Examination
Question 1
A 45-year-old male presents to the clinic requiring a full-mouth
series of intraoral radiographs. While configuring the intraoral
X-ray unit, the dental therapist reviews the statutory
requirements under the UK Ionising Radiation (Medical
Exposure) Regulations (IR(ME)R). Which of the following
statements accurately defines the legal role of the individual
who takes clinical responsibility for an individual medical
exposure and ensures it is justified?
A) The Referrer, who must be a registered dental hygienist or
dental therapist exclusively.
B) Correct Answer: The Practitioner, who must be a
registered medical or dental professional adequately
trained to justify the exposure. Rationale: Under
IR(ME)R, the "Practitioner" is the specified professional
entitled to justify a medical exposure. They must weigh the
potential clinical benefits against the radiation detriment.
While a Referrer requests the radiograph and an Operator
physically takes it, only an appointed Practitioner can
perform the legal act of justification.
C) The Operator, whose sole legal duty is to select the physical
exposure parameters on the control panel.
D) The Medical Physics Expert, who takes direct daily clinical
responsibility for individual patient exposures.
,Question 2
A dental nurse is taking a routine adult bitewing radiograph
using the paralleling technique with a rectangular collimator
and a digital sensor. The resulting image displays a distinct
blank, unexposed white area shape cut off on one side of the
digital image matrix. What technical error caused this artifact,
and how should it be corrected?
A) Over-development of the digital sensor matrix; replace the
sensor assembly immediately.
B) Correct Answer: Cone-cutting; ensure the X-ray
beam is perfectly centered over the sensor positioning
ring to encapsulate the active field. Rationale: Cone-
cutting occurs when the X-ray beam is not properly aligned
with the image receptor, causing part of the rectangular or
circular collimated beam to miss the sensor. This results in an
unexposed white zone. Utilizing a positioning holder with an
alignment ring ensures the beam completely encompasses the
receptor field.
C) Severe forward elongation from an excessive vertical
angulation of the tube head assembly.
D) Dynamic back-scattering caused by placing the digital sensor
completely backward in the holder.
Question 3
During a quality assurance audit of a dental practice's panoral
radiography unit, the Radiation Protection Advisor (RPA) notes
that the X-ray tube head operates at 70 kVp. According to the
UK Guidance Notes for Dental Practitioners, what is the
mandatory minimum total filtration thickness required for a
dental X-ray set operating between 60 kVp and 70 kVp?
A) 1.5 mm aluminum equivalent.
B) Correct Answer: 2.0 mm aluminum equivalent.
Rationale: Guidelines stipulate that for dental X-ray
equipment operating up to 70 kVp, the minimum total
,filtration (inherent plus added filtration) must be 2.0 mm
aluminum equivalent. For units operating above 70 kVp, the
requirement increases to 2.5 mm. Filtration removes low-
energy, long-wavelength photons that would otherwise be
absorbed by the patient's skin without contributing to image
formation.
C) 2.5 mm aluminum equivalent.
D) 0.5 mm lead equivalent.
Question 4
A 28-year-old female who is currently 14 weeks pregnant
requires root canal treatment on her lower right first molar. She
is highly anxious about the risk of diagnostic X-rays to her
unborn child. What is the correct pharmacological and safety
approach regarding dental radiography during pregnancy
under current UK guidelines?
A) Radiographs are strictly legally prohibited throughout the
entire duration of a pregnancy.
B) Correct Answer: Radiographs can be safely taken
if clinically indicated and justified, as the primary
beam is directed away from the abdomen and pelvic
fetal dose is negligible. Rationale: Under current UK
guidelines and IR(ME)R, pregnancy is not an absolute
contraindication to dental radiography. Because the primary
beam is collimated and targeted at the maxillofacial region,
the scatter radiation dose reaching the fetus is extremely low
(less than 0.01 mSv), meaning routine lead aprons are not
required, though clear psychological reassurance should be
provided.
C) Lead aprons must be layered three times over the patient's
thorax and abdomen for all intraoral films.
D) The exposure time must be doubled to overcome the
increased bone density changes caused by pregnancy.
Question 5
, A dental practitioner is interpreting a panoramic radiograph of
a 62-year-old female. The practitioner observes a well-
demarcated, multilocular radiolucency with a "soap-bubble"
appearance located within the posterior body and ramus of the
left mandible. The lesion has caused significant expansion of
the cortical plates and root resorption of the adjacent molars.
What is the most likely radiographical diagnosis?
A) Periapical cemento-osseous dysplasia.
B) Correct Answer: Ameloblastoma. Rationale: An
ameloblastoma is a benign but locally aggressive odontogenic
tumor most commonly found in the posterior mandible. Its
classic radiographic presentation is a multilocular, well-
defined radiolucency often described as having a "soap-
bubble" or "honeycomb" appearance, frequently associated
with cortical plate expansion, tooth displacement, and root
resorption.
C) Radicular cyst secondary to chronic pulp necrosis.
D) Osteoradionecrosis stemming from localized vascular
insufficiency.
Question 6
While reviewing the physical principles of X-ray generation, a
dental student notes that electron interactions with the
tungsten target produce two types of radiation spectra:
Bremsstrahlung (continuous) and Characteristic radiation.
What physical event triggers the production of Characteristic X-
ray photons?
A) A high-speed incident electron passes close to the tungsten
nucleus, slowing down and changing direction.
B) Correct Answer: An incident electron ejects an
inner-shell (K-shell) orbital electron from a tungsten
atom, causing an outer-shell electron to drop into the
vacancy. Rationale: Characteristic radiation occurs when
an incoming electron possesses enough kinetic energy to knock
an inner-shell electron out of its orbit. When an electron from
QUESTIONS 100 COMPLETE DENTAL
PRACTICE TEST BANK WITH ANSWERS
BOLDED and COMPREHENSIVE
RATIONALES UPDATED 2026
BDA Dental Radiography and Radiology Practice
Examination
Question 1
A 45-year-old male presents to the clinic requiring a full-mouth
series of intraoral radiographs. While configuring the intraoral
X-ray unit, the dental therapist reviews the statutory
requirements under the UK Ionising Radiation (Medical
Exposure) Regulations (IR(ME)R). Which of the following
statements accurately defines the legal role of the individual
who takes clinical responsibility for an individual medical
exposure and ensures it is justified?
A) The Referrer, who must be a registered dental hygienist or
dental therapist exclusively.
B) Correct Answer: The Practitioner, who must be a
registered medical or dental professional adequately
trained to justify the exposure. Rationale: Under
IR(ME)R, the "Practitioner" is the specified professional
entitled to justify a medical exposure. They must weigh the
potential clinical benefits against the radiation detriment.
While a Referrer requests the radiograph and an Operator
physically takes it, only an appointed Practitioner can
perform the legal act of justification.
C) The Operator, whose sole legal duty is to select the physical
exposure parameters on the control panel.
D) The Medical Physics Expert, who takes direct daily clinical
responsibility for individual patient exposures.
,Question 2
A dental nurse is taking a routine adult bitewing radiograph
using the paralleling technique with a rectangular collimator
and a digital sensor. The resulting image displays a distinct
blank, unexposed white area shape cut off on one side of the
digital image matrix. What technical error caused this artifact,
and how should it be corrected?
A) Over-development of the digital sensor matrix; replace the
sensor assembly immediately.
B) Correct Answer: Cone-cutting; ensure the X-ray
beam is perfectly centered over the sensor positioning
ring to encapsulate the active field. Rationale: Cone-
cutting occurs when the X-ray beam is not properly aligned
with the image receptor, causing part of the rectangular or
circular collimated beam to miss the sensor. This results in an
unexposed white zone. Utilizing a positioning holder with an
alignment ring ensures the beam completely encompasses the
receptor field.
C) Severe forward elongation from an excessive vertical
angulation of the tube head assembly.
D) Dynamic back-scattering caused by placing the digital sensor
completely backward in the holder.
Question 3
During a quality assurance audit of a dental practice's panoral
radiography unit, the Radiation Protection Advisor (RPA) notes
that the X-ray tube head operates at 70 kVp. According to the
UK Guidance Notes for Dental Practitioners, what is the
mandatory minimum total filtration thickness required for a
dental X-ray set operating between 60 kVp and 70 kVp?
A) 1.5 mm aluminum equivalent.
B) Correct Answer: 2.0 mm aluminum equivalent.
Rationale: Guidelines stipulate that for dental X-ray
equipment operating up to 70 kVp, the minimum total
,filtration (inherent plus added filtration) must be 2.0 mm
aluminum equivalent. For units operating above 70 kVp, the
requirement increases to 2.5 mm. Filtration removes low-
energy, long-wavelength photons that would otherwise be
absorbed by the patient's skin without contributing to image
formation.
C) 2.5 mm aluminum equivalent.
D) 0.5 mm lead equivalent.
Question 4
A 28-year-old female who is currently 14 weeks pregnant
requires root canal treatment on her lower right first molar. She
is highly anxious about the risk of diagnostic X-rays to her
unborn child. What is the correct pharmacological and safety
approach regarding dental radiography during pregnancy
under current UK guidelines?
A) Radiographs are strictly legally prohibited throughout the
entire duration of a pregnancy.
B) Correct Answer: Radiographs can be safely taken
if clinically indicated and justified, as the primary
beam is directed away from the abdomen and pelvic
fetal dose is negligible. Rationale: Under current UK
guidelines and IR(ME)R, pregnancy is not an absolute
contraindication to dental radiography. Because the primary
beam is collimated and targeted at the maxillofacial region,
the scatter radiation dose reaching the fetus is extremely low
(less than 0.01 mSv), meaning routine lead aprons are not
required, though clear psychological reassurance should be
provided.
C) Lead aprons must be layered three times over the patient's
thorax and abdomen for all intraoral films.
D) The exposure time must be doubled to overcome the
increased bone density changes caused by pregnancy.
Question 5
, A dental practitioner is interpreting a panoramic radiograph of
a 62-year-old female. The practitioner observes a well-
demarcated, multilocular radiolucency with a "soap-bubble"
appearance located within the posterior body and ramus of the
left mandible. The lesion has caused significant expansion of
the cortical plates and root resorption of the adjacent molars.
What is the most likely radiographical diagnosis?
A) Periapical cemento-osseous dysplasia.
B) Correct Answer: Ameloblastoma. Rationale: An
ameloblastoma is a benign but locally aggressive odontogenic
tumor most commonly found in the posterior mandible. Its
classic radiographic presentation is a multilocular, well-
defined radiolucency often described as having a "soap-
bubble" or "honeycomb" appearance, frequently associated
with cortical plate expansion, tooth displacement, and root
resorption.
C) Radicular cyst secondary to chronic pulp necrosis.
D) Osteoradionecrosis stemming from localized vascular
insufficiency.
Question 6
While reviewing the physical principles of X-ray generation, a
dental student notes that electron interactions with the
tungsten target produce two types of radiation spectra:
Bremsstrahlung (continuous) and Characteristic radiation.
What physical event triggers the production of Characteristic X-
ray photons?
A) A high-speed incident electron passes close to the tungsten
nucleus, slowing down and changing direction.
B) Correct Answer: An incident electron ejects an
inner-shell (K-shell) orbital electron from a tungsten
atom, causing an outer-shell electron to drop into the
vacancy. Rationale: Characteristic radiation occurs when
an incoming electron possesses enough kinetic energy to knock
an inner-shell electron out of its orbit. When an electron from
