DANB RADIOLOGY EXAM SCRIPT 2026
COMPLETE QUESTIONS AND CORRECT
ANSWERS GRADED A+
◉ What is the emulsion composed of? Answer: gelatin and silver halide
crystals
◉ What determines the speed of dental films? Answer: size of crystals,
thickness of emulsion, radiosensitive dyes
◉ What is the purpose of the lead foil? Answer: absorb scatter radiation
and prevent fogging
◉ How does film speed correlate with definition and detail? Answer:
faster film = lower definition and detail
◉ What speed films are most commonly used? Answer: D, E, F
◉ size film used for PA's on small children. Answer: #0
◉ size film used for BW on adults when only one film is taken on each
side. Answer: #3
,◉ size film used for anterior PA's for patients with narrow arches.
Answer: #1
◉ size film used for PA's on adults. Answer: #2
◉ size film used for BW on adults. Answer: #2
◉ size film used for occlusals on adults. Answer: #4
◉ What is the purpose of the embossed dot. Answer: to distinguish b/w
patient's right and left side
◉ What is the latent image. Answer: invisible image (remains like this
until film is processed)
◉ What happens in the developer. Answer: reduces the exposed silver
halide crystals to black metallic silver
◉ What happens in the fixer. Answer: removes the unexposed silver
halide crystals
◉ how long does film stay in the developer. Answer: 5 min
,◉ how long are films fixed. Answer: 10 min (dbl the development time)
◉ how long does the first rinse last. Answer: 20 seconds
◉ how long is the final rinse. Answer: 20 min
◉ what is the optimum processing temp. Answer: 68 degrees F
◉ when can the films be exposed to white light. Answer: after 2-3 min
of fixing if needed
◉ what causes film fogging. Answer: -old or contaminated processing
solutions
-exposure to chemical fumes
-faulty safelight
-scatter radiation
◉ what would cause a film to be too light. Answer: -underexposure
-underdevelopment
-depleted developer solution
-excessive fixation (takes all crystals off)
, ◉ what would cause a film to be too dark. Answer: -overexposure
-overdevelopment
-developer is too strong
-not enough fixation
-exposure to white light
-improper safelighting
◉ What causes a HERRINGBONE effect. Answer: film placed
backwards
◉ what would happen to a film that is placed in the fixer prior to
development. Answer: blank or clear
(takes all of the crystals off)
◉ what is reticulation. Answer: cracking of the emulsion caused by
excessive temp diff. b/w any darkroom solutions
◉ how would a film appear if submerged totally in the developer but not
in the fixer. Answer: top of film delineated by a straight line then dark
◉ film submerged totally in fixer but not in developer. Answer: part that
was fixed but not developed would be clear
COMPLETE QUESTIONS AND CORRECT
ANSWERS GRADED A+
◉ What is the emulsion composed of? Answer: gelatin and silver halide
crystals
◉ What determines the speed of dental films? Answer: size of crystals,
thickness of emulsion, radiosensitive dyes
◉ What is the purpose of the lead foil? Answer: absorb scatter radiation
and prevent fogging
◉ How does film speed correlate with definition and detail? Answer:
faster film = lower definition and detail
◉ What speed films are most commonly used? Answer: D, E, F
◉ size film used for PA's on small children. Answer: #0
◉ size film used for BW on adults when only one film is taken on each
side. Answer: #3
,◉ size film used for anterior PA's for patients with narrow arches.
Answer: #1
◉ size film used for PA's on adults. Answer: #2
◉ size film used for BW on adults. Answer: #2
◉ size film used for occlusals on adults. Answer: #4
◉ What is the purpose of the embossed dot. Answer: to distinguish b/w
patient's right and left side
◉ What is the latent image. Answer: invisible image (remains like this
until film is processed)
◉ What happens in the developer. Answer: reduces the exposed silver
halide crystals to black metallic silver
◉ What happens in the fixer. Answer: removes the unexposed silver
halide crystals
◉ how long does film stay in the developer. Answer: 5 min
,◉ how long are films fixed. Answer: 10 min (dbl the development time)
◉ how long does the first rinse last. Answer: 20 seconds
◉ how long is the final rinse. Answer: 20 min
◉ what is the optimum processing temp. Answer: 68 degrees F
◉ when can the films be exposed to white light. Answer: after 2-3 min
of fixing if needed
◉ what causes film fogging. Answer: -old or contaminated processing
solutions
-exposure to chemical fumes
-faulty safelight
-scatter radiation
◉ what would cause a film to be too light. Answer: -underexposure
-underdevelopment
-depleted developer solution
-excessive fixation (takes all crystals off)
, ◉ what would cause a film to be too dark. Answer: -overexposure
-overdevelopment
-developer is too strong
-not enough fixation
-exposure to white light
-improper safelighting
◉ What causes a HERRINGBONE effect. Answer: film placed
backwards
◉ what would happen to a film that is placed in the fixer prior to
development. Answer: blank or clear
(takes all of the crystals off)
◉ what is reticulation. Answer: cracking of the emulsion caused by
excessive temp diff. b/w any darkroom solutions
◉ how would a film appear if submerged totally in the developer but not
in the fixer. Answer: top of film delineated by a straight line then dark
◉ film submerged totally in fixer but not in developer. Answer: part that
was fixed but not developed would be clear
