Dental x ray film processing
Download
1 / 34

Dental X-ray Film Processing - PowerPoint PPT Presentation


  • 769 Views
  • Uploaded on
  • Presentation posted in: General

Dental X-ray Film Processing. Film Processing. Refers to a series of steps that produce a visible permanent image on a dental radiograph The process consists of two major steps that transform the latent image into a visible image and preserves that image permanently. Manual Film Processing.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha

Download Presentation

Dental X-ray Film Processing

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript



Film processing
Film Processing

  • Refers to a series of steps that produce a visible permanent image on a dental radiograph

  • The process consists of two major steps that transform the latent image into a visible image and preserves that image permanently.



From latent image to visible image
From Latent Image to Visible Image:

  • During the manual development process, the film undergoes a series of reactions with chemical solutions.

  • Developer

    • rinsed

  • Fixer

    • Rinsed

    • Dried



Selective reduction
Selective Reduction

  • Selective reduction refers to

    • the reduction of theenergized, exposed silver halide crystals into black metallic silver.

    • This happens in the developer

    • Unenergized, unexposed silver halide crystals are removed from the film.

    • This happens in the fixer



Processing procedures
Processing Procedures

  • The film is first placed in a chemical called the developing solution .

    • This chemical can distinguish between the exposed and unexposed silver halide crystals.

  • The silver halide crystals that are exposed will become black or gray metallic silver, while the unexposed silver halide crystals will remain unaffected.


Processing procedures1
Processing Procedures

  • Next, the film is placed in a solution called fixer for a specific amount of time. This solution removes the unexposed silver halide crystals

  • This process creates the clear or white areas on the film

  • Most importantly, the black metallic silver remains on the film


The resultant image
The resultant image

  • The image is made up of black, white and gray areas.

  • These are formed from the types of structures exposed on the film.



Radiolucent
RADIOLUCENT

  • A radiolucent structure is one that readilypermits the passage of the x-ray beam and allows more x-rays to reach the film.

  • If more x-rays reach the film, more silver halide crystals within the film emulsion are exposed and energized.

  • This results in increased deposits of black metallic silver.

  • A radiograph with large deposits of black metallic silver appears black, or radiolucent.


Radiopaque
RADIOPAQUE

  • A radiopaque structure is one that resists the passage of x-rays and therefore limits the amount of radiation that reaches the film.

  • These unexposed halide crystals are removed from the film during processing. No black metallic silver deposits will show on the film.

  • Therefore, a radiopaque film appears white or clear.


Processing chemistry
Processing Chemistry

  • Necessary to have the proper solutions for adequate processing

  • These chemicals can come in ready use liquid, liquid concentrate, or in a powder form

  • Chemicals should be fresh for proper results, and changed on a 3-4 week basis depending on frequency of use


Developer solution
Developer Solution

  • The developing solution is also known as the reducing solution. Why?

  • The purpose of the developer is to reduce the exposed halide crystals chemically into black metallic silver.

  • The developer also softens the film emulsion.


Developer chemicals
Developer Chemicals

  • Hydroquinone

    • its purpose is to slowly generate black tones and contrast.

    • To be effective, the temperature should be 68 degrees or higher

  • Elon

    • quickly generates the many gray tones on a radiograph

  • See page 89, Table 9-1 of your text for all of the chemical components of the developing solution


The fixer solution
The Fixer Solution

  • The purpose of the fixing agent is to remove or “clear” all unexposed and undeveloped silver halide crystals from the film emulsion

  • By doing this, the black image produced by the developer becomes readily distinguishable.


The fixer chemicals
The Fixer Chemicals

  • Sodium thiosulfate

    • The clearing agent

  • Potassium alum

    • The hardening agent – hardens the film emulsion

  • Acidifier

    • This neutralizes the alkaline developer, and stops the developing process

  • Preservative


Manual processing
Manual Processing

  • This is a much more technique sensitive process

  • Temperature effects duration of films in baths

  • Process: Developer, rinse, Fixer, rinse, dry

  • A thermometer is kept in the chemical baths to accurately estimate the time needed to process the films

  • A timer is needed to identify when to move the films into the next bath

  • Film hangers are also necessary to dry the films thoroughly after development


Manual film processing1
Manual Film Processing

Processing Tanks

Film Hangers



The darkroom1
The Darkroom

  • Provides an environment in which x-ray films can be handled and processed.

  • Room lighting with incandescent lighting is acceptable for performing tasks such as stocking and cleaning or replenishing solutions

  • Some important considerations for the darkroom:

    • Size of the room itself

    • Location in the building

    • Proper lighting equipment

    • Temperature and humidity control


Lighting in the darkroom
Lighting in the Darkroom:

  • To be a “darkroom” the room cannot emit any white light

  • The darkroom should be

    • light-tight, with no light leaks

    • this could cause film fog

    • an overall dull graying of the film which makes interpretation difficult


Safe lighting
Safe lighting

  • Safe lighting is necessary for illumination during the development process.

  • A safelight consists of a low wattage bulb (7 or 15 watts) with a safelight filter


Safe lighting1
Safe lighting

  • The filter removes the blue green portion of visible light, and allows only light from the red-orange portion of the light spectrum through which does not harm the film.

  • A working distance of at least four feet must be kept to prevent exposure of the dental films being processed






Automatic processing1
Automatic Processing

  • An auto processor simplifies the development process:

  • It uses racks to move the films in and out of the developer, fixer, and water bath in just the right amount of time needed.

  • It also dries the films when complete, allowing them to be handled right away

  • Sequence is: develop, fix, rinse. NO RINSING takes place in between the developer and the fixer with automatic processing.


The auto processor
The Auto Processor:

  • This allows for a more controlled method of processing films.

  • The major advantage is the time saved in developing – on the average, 4-6 minutes, as opposed to an hour for manual!

  • Other advantages include:

    • Less space is needed (no darkroom required)

    • Less equipment also (no tanks, plumbing requirements, etc.)


Replenishing solutions and maintenance
Replenishing Solutionsand Maintenance


Chemical maintenance
Chemical Maintenance:

  • Evaporation occurs with both the fixer and developer from use and exposure to air

  • This can decrease the strength and volume

  • A replenisher (a super concentrated chemical solution) can be added to replace what has been lost.

  • Replenishers can be added on a daily basis to maintain chemical freshness



ad
  • Login