Radiology PP-L Elements of Processing

  1. Halides in dental film are ______ and ______
    Silver + Halogen
  2. _______ and _______ are 2 types of SHC’s (Silver Halide crystals) found in film’s emulsion
    Silver bromide (80-99%) and Silver Iodide (1%)
  3. Silver halide crystals absorb
    x-radiation and stores energy
  4. No density=
    energized SHC’s
  5. A latent image is formed when
    Stored energy within crystals forms pattern within emulsion
  6. Ionization is when
    an electron is removed from an atom leaving one + and one- ion
  7. In Conventional Dental Film: Exposed Silver Bromide Crystals are _______ , causing the _____ and _____ atoms to separate. (release of electrons)
    • ionized
    • silver and bromine atoms
  8. Clusters of neutral silver atoms are known as
    latent image sites or centers
  9. TRADITIONAL FILM PROCESSING: is when film is immersed in _____ solutions
    developer and fixer chemical
  10. What are the steps of film processing
    • 1. Film is placed in “developer” solution for a specific   amount of time depending on the temperature
    • 2. Film is then rinsed with water to remove developer solution
    • 3. Next, film is placed in “fixer” solution
    • 4. Film is placed in water again to remove all solutions   and then dried
  11. Developer identifies between the _____ and ______ silver halide crystals. Then the developer reduces the exposed silver halide crystals to ________and creates _____ areas on the radiograph
    • exposed and unexposed
    • black metallic silver (“reduction”)
    • dark/black (RL)
  12. Fixer removes the ________ and ______ silver halide crystals and creates ______ areas on a radiograph
    • unexposed and unenergized
    • white or clear
  13. REDUCTION is a chemical reaction where the ______ portion of the exposed silver halide crystal (SHC) is ______  resulting in _________ and refers only to the _______
    • halide
    • removed
    • precipitated black metallic silver
    • developer
  14. SELECTIVE REDUCTION are when exposed SHC’s are reduced to ________ (developer), while the unexposed SHC’s are removed from the _______ and refers to both ______ and ______
    • black metallic silver
    • film (fixer).
    • developer and fixer
  15. Radiolucent areas _____ the passage of the x-ray beam and allows _____ x-rays to reach the film
    • Permits
    • more
  16. Radiopaque areas ______ the passage of the x-ray beam, _____ the amount of x-ray that reaches the film
    • resists
    • limiting
  17. What are the ingredients in the developer
    • Developing or “Reducing” Agents
    • Preservative
    • Accelerator (activator)
    • Restrainer
  18. What are the two developing agents and what are their function
    • 1.Hydroquinine(temperature-sensitive: Optimal temp 68 degrees): Slowly generates the black tones and sharp contrast
    • 2. Elon (“metol”)(not temperature-sensitive): Quickly generates the gray tones
  19. What is the preservative agent in the developer and what is it's function
    Sodium Sulfite: Prevents rapid oxidation/extends life of developing agents
  20. What is the accelerator agent in the developer and what it its function
    Sodium Carbonate: Activates developing agents by providing alkaline(high PH environment) Softens the emulsion
  21. What is the restrainer agent in the developer
    Potassium Bromide: Prevents development of unexposed SHC’s
  22. Hydroquinine and Elon (developing agents): ­NOT stable in the
    presence of air
  23. What are the ingredients in the fixer
    • Fixing Agent “Clearing Agent”
    • Preservative
    • Hardening Agent
    • Acidifier
  24. What are the chemicals in the Fixing Agent “Clearing Agent” and what function does it serve
    • Sodium thiosulfate or Ammonium thiosulfate   “hypo”: Removes unexposed, undeveloped SHC’s from emulsion
    • Clears the film to allow the black image produced by the developer to become readily distinguished
  25. What is the chemical in the preservatives of the fixer and what function does it serve
    Sodium Sulfite: Prevents chemical deterioration
  26. What is the chemical in the hardening agent of the fixer and what function does it serve
    Potassium Alum: Shrinks and hardens the gelatin in the emulsion
  27. What is the chemical in the acidifier in the fixer and what function does it serve
    Sulfuric Acid or Acetic Acid: Provides acidic environment required for fixing Neutralizes the alkaline developer and stops further development (of unexposed SHC’s)
  28. What kind of bulb is used for the safe light in the dark room
    low wattage bulb 15 watts or less and a proper red filter
  29. What is the ideal solution temp/developer time/ rinse time/ fixer time/ wash time for manual processing
    • 68 degrees
    • 5 minutes
    • Half a minute
    • 10 minutes
    • 20 minutes
  30. What is the Wet Reading” of Radiographs
    Remove film from the fixer after 2 minutes, rinse to remove fixer solution, shake off excess water for a quick read. Films must then be returned to the fixer solution to finish the 10 minute cycle in fixer and 20 minute final wash
  31. During Automatic Film Processing what step is eliminated
    Rinse between the developer and fixer
  32. Automatic Processing requires more
    concentrated solutions and higher temperatures
  33. Temperature of the Automatic processor must be between
    80° -95°F
  34. What are the possible causes of a light radiograph
    • ­Films not in developer long enough (Underdeveloped/Insufficient time)
    • ­Low developer temperature
    • ­Depleted or contaminated developer solution
  35. What are the possible causes of a dark radiograph
    • ­Excessive development time
    • ­High developer temperature
    • ­Overactive developer solution
  36. What is reticulation and what is it caused by
    • Film appears cracked­
    • Caused by sudden temperature changes in solutions
  37. When there are chemical splashes on film prior to processing the white spots are caused by the  _________ and the black spots are caused by the _________
    • fixer
    • developer
  38. What are the possible causes of Yellow-Brown Stains
    • ­Exhausted developer or fixer
    • ­Insufficient fixation time
    • ­Insufficient rinsing
  39. What is a developer cutoff and what is it caused by
    • Developer solution level too low, causing a straight, clear border
    • portion of the film was never developed and cleared by the fixer
  40. What is a fixer cutoff and what is it caused by
    • Fixer solution level too low: straight black border
    • Portion of the film was not fixed
  41. What are the causes of film fog
    • Outdated (expired) film
    • Safelight: improper wattage or Over-exposed to safelight/light leak in darkroom
    • Improper film storage
    • Contaminated processing solutions
    • High developer temp
  42. The longer the film is in water the
    softer the emulsion
Card Set
Radiology PP-L Elements of Processing
Radiology PP-L Elements of Processing