Chapter 39Dental Film and Processing
Radiographs
Chapter 39Dental Film and Processing
Radiographs
Copyright 2003, Elsevier Science (USA).
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Introduction Introduction
Film processing procedures have a direct effect on the quality of a radiograph.
The dental assistant must be knowledgeable about the types of dental film and film-holding devices and must also thoroughly understand the processing procedures to produce high-quality diagnostic dental radiographs.
Film processing procedures have a direct effect on the quality of a radiograph.
The dental assistant must be knowledgeable about the types of dental film and film-holding devices and must also thoroughly understand the processing procedures to produce high-quality diagnostic dental radiographs.
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TerminologyTerminology
Film is the correct term to use before it has been processed. The film is in the packet, the film is placed in the bite-block, and the film is exposed and processed.
After the film has been processed, it becomes a radiograph.
Film is the correct term to use before it has been processed. The film is in the packet, the film is placed in the bite-block, and the film is exposed and processed.
After the film has been processed, it becomes a radiograph.
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Types of Film Holders and Beam Alignment Devices Types of Film Holders and Beam Alignment Devices
A wide variety of types of intraoral film holders are available on the market today.
A basic film holder is the disposable styrofoam bite-block with a backing plate and a slot for film retention.
The EEZEE-Grip (formerly the Snap-A-Ray) is a double-ended instrument that holds the film between two serrated plastic grips that can be locked into place.
The Endoray device is used to take radiographs when instruments are in the canal.
Uni-bite devices are made by the Rinn Corporation.
A wide variety of types of intraoral film holders are available on the market today.
A basic film holder is the disposable styrofoam bite-block with a backing plate and a slot for film retention.
The EEZEE-Grip (formerly the Snap-A-Ray) is a double-ended instrument that holds the film between two serrated plastic grips that can be locked into place.
The Endoray device is used to take radiographs when instruments are in the canal.
Uni-bite devices are made by the Rinn Corporation.
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Fig. 39-1 Styrofoam-type disposable bite-block. Fig. 39-1 Styrofoam-type disposable bite-block.
Fig. 39-1Fig. 39-1
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Fig. 39-2 The EEZEE-Grip (formerly the Snap-A-Ray) film holder.Fig. 39-2 The EEZEE-Grip (formerly the Snap-A-Ray) film holder.
Fig. 39-2Fig. 39-2
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Fig. 39-3 The Endoray is shown with endodontic instruments placed in wax to demonstrate placement of the film holder when instruments are in the canal. Fig. 39-3 The Endoray is shown with endodontic instruments placed in wax to demonstrate placement of the film holder when instruments are in the canal.
Fig. 39-3Fig. 39-3
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Fig. 39-4 The new Rinn XCP are color-coded for easier assembly. The red instruments are for bitewing placement, the yellow are for posterior placement, and the blue are for anterior placement.
Fig. 39-4 The new Rinn XCP are color-coded for easier assembly. The red instruments are for bitewing placement, the yellow are for posterior placement, and the blue are for anterior placement.
Fig. 39-4Fig. 39-4
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Dental X-Ray FilmDental X-Ray Film
Film used in dental radiography is photographic film that has been adapted for dental use.
A photographic image is produced on dental x-ray film when it is exposed to x-rays that have passed through teeth and adjacent tissues.
The dental assistant must understand the composition of x-ray film and latent image formation that result in increased patient exposure to x-rays.
Film used in dental radiography is photographic film that has been adapted for dental use.
A photographic image is produced on dental x-ray film when it is exposed to x-rays that have passed through teeth and adjacent tissues.
The dental assistant must understand the composition of x-ray film and latent image formation that result in increased patient exposure to x-rays.
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Film CompositionFilm Composition
Intraoral dental film is made up of a semiflexible, clear cellulose acetate film base that is coated on both sides with an emulsion of silver bromide, silver halide, and silver iodide that are sensitive to radiation.
Intraoral dental film is made up of a semiflexible, clear cellulose acetate film base that is coated on both sides with an emulsion of silver bromide, silver halide, and silver iodide that are sensitive to radiation.
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Latent Image Formation Latent Image Formation When the radiation interacts with the silver
halide crystals in the film emulsion, the image on the film is produced.
The image is not visible before processing and is called the latent image.
An example of another type of latent image is fingerprints. If you touch an item, you leave your fingerprints even though you cannot see them on that item. However, when that item is treated, your fingerprints become visible.
When the radiation interacts with the silver halide crystals in the film emulsion, the image on the film is produced.
The image is not visible before processing and is called the latent image.
An example of another type of latent image is fingerprints. If you touch an item, you leave your fingerprints even though you cannot see them on that item. However, when that item is treated, your fingerprints become visible.
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Film SpeedFilm Speed
Film speed refers to the amount of radiation required to produce a radiograph of standard density (darkness). Film speed is determined by the following: • The size of the silver halide crystals. • The thickness of the emulsion.• The presence of special radiosensitive
dyes.
Film speed refers to the amount of radiation required to produce a radiograph of standard density (darkness). Film speed is determined by the following: • The size of the silver halide crystals. • The thickness of the emulsion.• The presence of special radiosensitive
dyes.
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Film Speed- cont’dFilm Speed- cont’d The film speed determines how much exposure
time is required to produce the image on the film.
A fast film requires less radiation, and the film responds more quickly because the silver halide crystals in the emulsion are larger.
The larger the crystals, the faster the film speed. This is the same principal as film speed on photographic film.
The “F” speed is the newest and fastest film on the market today and will reduce radiation exposure to the patient by 20% to 60% compared to E-speed film and D- speed film.
The film speed determines how much exposure time is required to produce the image on the film.
A fast film requires less radiation, and the film responds more quickly because the silver halide crystals in the emulsion are larger.
The larger the crystals, the faster the film speed. This is the same principal as film speed on photographic film.
The “F” speed is the newest and fastest film on the market today and will reduce radiation exposure to the patient by 20% to 60% compared to E-speed film and D- speed film.
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Fig. 39-7 “Insight” is the new F-speed film available from Kodak. (Courtesy Eastman Kodak Co, Rochester, NY.)Fig. 39-7 “Insight” is the new F-speed film available from Kodak. (Courtesy Eastman Kodak Co, Rochester, NY.)
Fig. 39-7Fig. 39-7
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Types of Dental FilmTypes of Dental Film
There are three types of x-ray film used in dental radiography: • Intraoral film • Extraoral film • Duplicating film
There are three types of x-ray film used in dental radiography: • Intraoral film • Extraoral film • Duplicating film
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Intraoral Film Intraoral Film Intraoral film is named because it is placed
inside the mouth during x-ray exposure. The intraoral x-ray film has emulsion on both
sides of the film instead of emulsion on only one side because it requires less radiation to produce an image.
To protect the film from light and moisture, the film is packaged and referred to as the film packet.
Intraoral film is named because it is placed inside the mouth during x-ray exposure.
The intraoral x-ray film has emulsion on both sides of the film instead of emulsion on only one side because it requires less radiation to produce an image.
To protect the film from light and moisture, the film is packaged and referred to as the film packet.
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Contents of the Film Packet Contents of the Film Packet Intraoral film packets are typically available
in boxes of 25, 100, or 150 films. The film packet may contain one film (one-
film packet) or two films (two-film packet). The boxes of film are labeled with the
following information: the type of film, film speed, number of films per individual packet, the total number of films in the box, and the film expiration date.
On one corner of the film packet is a small raised bump known as the identification dot.
Intraoral film packets are typically available in boxes of 25, 100, or 150 films.
The film packet may contain one film (one-film packet) or two films (two-film packet).
The boxes of film are labeled with the following information: the type of film, film speed, number of films per individual packet, the total number of films in the box, and the film expiration date.
On one corner of the film packet is a small raised bump known as the identification dot.
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Fig. 39-8 Contents of a dental film packet: lead foil, x-ray film, and black paper. Fig. 39-8 Contents of a dental film packet: lead foil, x-ray film, and black paper.
Fig. 39-8Fig. 39-8
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Fig. 39-5 Cross-sectional diagram of film base and emulsion.Fig. 39-5 Cross-sectional diagram of film base and emulsion.
Fig. 39-5Fig. 39-5
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The Film PacketThe Film Packet The black paper film wrapper inside the film
packet is a protective sheet that covers the film and shields it from light.
The thin lead foil sheet is positioned behind the film to shield the film from back-scattered (secondary) radiation that results in film fog.
The outer packet wrapping is a soft vinyl or paper wrapper that seals the film packet, protective black paper, and lead foil sheet.
The tube side is solid white and has the raised bump on one corner. When placed in the mouth, the white side (tube side) of the film must face the teeth and tubehead, and the raised dot must be toward the incisal/occlusal surface.
The black paper film wrapper inside the film packet is a protective sheet that covers the film and shields it from light.
The thin lead foil sheet is positioned behind the film to shield the film from back-scattered (secondary) radiation that results in film fog.
The outer packet wrapping is a soft vinyl or paper wrapper that seals the film packet, protective black paper, and lead foil sheet.
The tube side is solid white and has the raised bump on one corner. When placed in the mouth, the white side (tube side) of the film must face the teeth and tubehead, and the raised dot must be toward the incisal/occlusal surface.
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Fig. 39-9 A, The lead foil insert in this package has a raised diamond pattern across both ends. B, Radiograph showing the raised diamond pattern from the lead foil backing when the film is positioned backwards.
Fig. 39-9 A, The lead foil insert in this package has a raised diamond pattern across both ends. B, Radiograph showing the raised diamond pattern from the lead foil backing when the film is positioned backwards.
Fig. 39-9 ABFig. 39-9 AB
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Fig. 39-10 The white side of the film packet faces the tube. A, Size 4 occlusal film. B, Size 2 film; size 1 film. Fig. 39-10 The white side of the film packet faces the tube. A, Size 4 occlusal film. B, Size 2 film; size 1 film.
Fig. 39-10 ABFig. 39-10 AB
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Sizes of Film Sizes of Film Intraoral film packets come in five basic
sizes:• Child (#0)• Narrow anterior (#1) • Adult size (#2)• Preformed bitewing (#3)• Occlusal (#4)
Intraoral film packets come in five basic sizes:• Child (#0)• Narrow anterior (#1) • Adult size (#2)• Preformed bitewing (#3)• Occlusal (#4)
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Extraoral FilmExtraoral Film An extraoral film is one that is placed
outside of the mouth during x-ray exposure. Extraoral films are used to examine large
areas of the head or jaws. Examples of common extraoral films include
panoramic and cephalometric films. A panoramic film shows a panoramic
(wide) view of the upper and lower jaws on a single radiograph.
A cephalometric film shows the bony and soft tissue areas of the facial profile.
An extraoral film is one that is placed outside of the mouth during x-ray exposure.
Extraoral films are used to examine large areas of the head or jaws.
Examples of common extraoral films include panoramic and cephalometric films.
A panoramic film shows a panoramic (wide) view of the upper and lower jaws on a single radiograph.
A cephalometric film shows the bony and soft tissue areas of the facial profile.
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Fig. 39-11 A panoramic film. (Reprinted courtesy Eastman Kodak Co, Rochester, NY.)Fig. 39-11 A panoramic film. (Reprinted courtesy Eastman Kodak Co, Rochester, NY.)
Fig. 39-11Fig. 39-11
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Fig. 39-12 A cephalometric film. (Reprinted courtesy Eastman Kodak Co, Rochester, NY.)Fig. 39-12 A cephalometric film. (Reprinted courtesy Eastman Kodak Co, Rochester, NY.)
Fig. 39-12Fig. 39-12
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Extraoral Film Packaging Extraoral Film Packaging
Extraoral radiography uses a film-screen system. This means that the film is used in combination with intensifying screens.
Extraoral film is supplied in boxes of 50 or 100 films.
Extraoral film used in dental radiography is available in 5 x 7 inch and 8 x 10 inch size.
Extraoral film is not supplied in film packets. The film is stacked in the box much like a deck
of cards. Because there is no wrapper to protect the film
from exposure to light, the film must be loaded into a cassette in the darkroom.
Extraoral radiography uses a film-screen system. This means that the film is used in combination with intensifying screens.
Extraoral film is supplied in boxes of 50 or 100 films.
Extraoral film used in dental radiography is available in 5 x 7 inch and 8 x 10 inch size.
Extraoral film is not supplied in film packets. The film is stacked in the box much like a deck
of cards. Because there is no wrapper to protect the film
from exposure to light, the film must be loaded into a cassette in the darkroom.
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Fig. 39-13 Boxes of extraoral radiography film. (Courtesy Eastman Kodak Co, Rochester, NY.)Fig. 39-13 Boxes of extraoral radiography film. (Courtesy Eastman Kodak Co, Rochester, NY.)
Fig. 39-13Fig. 39-13
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Film Cassette Film Cassette A cassette is a plastic or metal case used in
extraoral radiography to hold the film and protect it from exposure to light. Cassettes are available in rigid or flexible styles.
To tell the patient’s left from the right as on intraoral films, the front of the cassettes must be marked with lead letters “L” (left side) or “R” (right side).This is because there is no raised dot on extraoral film.
The front side of the cassette must always face the patient during exposure.
A cassette is a plastic or metal case used in extraoral radiography to hold the film and protect it from exposure to light. Cassettes are available in rigid or flexible styles.
To tell the patient’s left from the right as on intraoral films, the front of the cassettes must be marked with lead letters “L” (left side) or “R” (right side).This is because there is no raised dot on extraoral film.
The front side of the cassette must always face the patient during exposure.
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Fig. 39-14 The dental assistant removes a film from a flexible film cassette.Fig. 39-14 The dental assistant removes a film from a flexible film cassette.
Fig. 39-14Fig. 39-14
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Intensifying Screen Intensifying Screen An intensifying screen intensifies or increases
the effect of the radiation and thus decreases the amount of exposure time needed.
The intensifying screen is coated with a material called phosphor that gives off light when struck by x-radiation.
The film inside the cassette is sandwiched between the intensifying screens and is affected by both the light produced by the phosphor and the x-radiation.
However, there is a slight loss of image detail as a result of the intensified x-ray beam because the light produces a halo effect at the edge of the image field.
An intensifying screen intensifies or increases the effect of the radiation and thus decreases the amount of exposure time needed.
The intensifying screen is coated with a material called phosphor that gives off light when struck by x-radiation.
The film inside the cassette is sandwiched between the intensifying screens and is affected by both the light produced by the phosphor and the x-radiation.
However, there is a slight loss of image detail as a result of the intensified x-ray beam because the light produces a halo effect at the edge of the image field.
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Types of Screen Film Used in Extraoral RadiographyTypes of Screen Film Used in Extraoral Radiography
Green-sensitive: This type of film is used with cassettes that have rare earth intensifying screens.
Blue-sensitive: This type of film is used with cassettes that have calcium tungstate intensifying screens.
Green-sensitive: This type of film is used with cassettes that have rare earth intensifying screens.
Blue-sensitive: This type of film is used with cassettes that have calcium tungstate intensifying screens.
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Fig. 39-15 Rigid film cassette with an intensifying screen.Fig. 39-15 Rigid film cassette with an intensifying screen.
Fig. 39-15Fig. 39-15
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Duplicating Radiographs Duplicating Radiographs Special duplicating film and a duplicating
machine is necessary to duplicate radiographs. Duplicating film is used only in a darkroom
setting and is never exposed to x-rays. The duplicating machine produces white light to
expose the film. Because the film is light-sensitive, the duplication process is performed in the darkroom with the safelight.
The longer the duplicating film is exposed to light, the lighter it will become. This is the opposite of x-ray film, which becomes darker when exposed to light.
Special duplicating film and a duplicating machine is necessary to duplicate radiographs.
Duplicating film is used only in a darkroom setting and is never exposed to x-rays.
The duplicating machine produces white light to expose the film. Because the film is light-sensitive, the duplication process is performed in the darkroom with the safelight.
The longer the duplicating film is exposed to light, the lighter it will become. This is the opposite of x-ray film, which becomes darker when exposed to light.
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Fig. 39-16 Example of a film duplicator.Fig. 39-16 Example of a film duplicator.
Fig. 39-16Fig. 39-16
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Dental X-Ray Film ProcessingDental X-Ray Film Processing Processing is a series of steps that changes the
latent image on the exposed film into a radiograph by producing a visible image on the film.
Proper processing is just as important as the exposure technique in producing diagnostic-quality radiographs.
Radiographs that are nondiagnostic because of poor processing techniques must be retaken, and the patient will be exposed to unnecessary radiation.
In many practices, intraoral films are processed in an automatic processor; however, it is still necessary to know how to process the film manually.
Processing is a series of steps that changes the latent image on the exposed film into a radiograph by producing a visible image on the film.
Proper processing is just as important as the exposure technique in producing diagnostic-quality radiographs.
Radiographs that are nondiagnostic because of poor processing techniques must be retaken, and the patient will be exposed to unnecessary radiation.
In many practices, intraoral films are processed in an automatic processor; however, it is still necessary to know how to process the film manually.
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Five Steps in Processing Dental Radiographs: Five Steps in Processing Dental Radiographs:
Development Rinsing Fixation Washing Drying
Development Rinsing Fixation Washing Drying
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DevelopingDeveloping
Developing is the first step in processing films.
A chemical solution called the developer is used.
The purpose of the developer is to chemically reduce the exposed silver halide crystals into black metallic silver.
The developer solution also softens the film emulsion during this process.
Developing is the first step in processing films.
A chemical solution called the developer is used.
The purpose of the developer is to chemically reduce the exposed silver halide crystals into black metallic silver.
The developer solution also softens the film emulsion during this process.
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RinsingRinsing
Rinsing the films is necessary to remove the developer from the film so that the development process stops.
Usually, agitating the film rack for 20 seconds is sufficient.
This must be done under safelight conditions.
Rinsing the films is necessary to remove the developer from the film so that the development process stops.
Usually, agitating the film rack for 20 seconds is sufficient.
This must be done under safelight conditions.
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FixingFixing The acidic fixing solution removes the unexposed
silver halide crystals from the film emulsion. The fixer also hardens the film emulsion during this
process. For permanent fixation, the film is kept in the fixer
for a minimum of 10 minutes. However, films may be removed from the fixing
solution after 3 minutes for viewing. Films that are not properly fixed will fade and turn
brown in a short time. Leaving films in the fixer for a long time (i.e., over a
weekend) can remove the image from the film.
The acidic fixing solution removes the unexposed silver halide crystals from the film emulsion.
The fixer also hardens the film emulsion during this process.
For permanent fixation, the film is kept in the fixer for a minimum of 10 minutes.
However, films may be removed from the fixing solution after 3 minutes for viewing.
Films that are not properly fixed will fade and turn brown in a short time.
Leaving films in the fixer for a long time (i.e., over a weekend) can remove the image from the film.
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Washing Washing Following fixation, a water bath is used to
wash the film. The washing step requires about 20 minutes
to thoroughly remove all excess chemicals from the emulsion.
Following fixation, a water bath is used to wash the film.
The washing step requires about 20 minutes to thoroughly remove all excess chemicals from the emulsion.
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DryingDrying
The final step in film processing is the drying of the films.
Films may be air-dried at room temperature in a dust-free area or placed in a heated drying cabinet.
Films must be completely dried before they can be handled for mounting and viewing.
The final step in film processing is the drying of the films.
Films may be air-dried at room temperature in a dust-free area or placed in a heated drying cabinet.
Films must be completely dried before they can be handled for mounting and viewing.
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Film Processing SolutionsFilm Processing Solutions
Film processing solutions are available in the following forms: • Powder • Ready-to-use liquid • Liquid concentrate
Film processing solutions are available in the following forms: • Powder • Ready-to-use liquid • Liquid concentrate
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Fig. 39-17 Kodak developer and fixer concentrated solutions. (Courtesy Eastman Kodak Co, Rochester, NY.) Fig. 39-17 Kodak developer and fixer concentrated solutions. (Courtesy Eastman Kodak Co, Rochester, NY.)
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The DarkroomThe Darkroom The term light-tight is often used to
describe the darkroom. To be light-tight, no light leaks can be
present. When you are in the darkroom with the light
turned off, no white light should be seen. X-ray film is extremely sensitive to visible
white light. Any leaks of white light can cause film fog. A
fogged film appears dull gray, lacks contrast, and is nondiagnostic.
The term light-tight is often used to describe the darkroom.
To be light-tight, no light leaks can be present.
When you are in the darkroom with the light turned off, no white light should be seen.
X-ray film is extremely sensitive to visible white light.
Any leaks of white light can cause film fog. A fogged film appears dull gray, lacks contrast, and is nondiagnostic.
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Types of Darkroom LightingTypes of Darkroom Lighting Room lighting: An overhead white light
that provides adequate lighting when performing tasks such as cleaning, restocking materials, and mixing chemicals is required.
Safelighting: A safelight is a low-intensity light in the red-orange spectrum. Safelighting provides enough illumination in the darkroom to process films safely without exposing or damaging the film.
Room lighting: An overhead white light that provides adequate lighting when performing tasks such as cleaning, restocking materials, and mixing chemicals is required.
Safelighting: A safelight is a low-intensity light in the red-orange spectrum. Safelighting provides enough illumination in the darkroom to process films safely without exposing or damaging the film.
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There must be a safe distance between the light and the working area, and to work quickly to keep the exposure to the safelight as short as possible.
Unwrapped films that are left too close to the safelight or exposed to the safelight for more than 2 to 3 minutes appear fogged.
A safelight must be placed a minimum of 4 feet away from the film and working area.
There must be a safe distance between the light and the working area, and to work quickly to keep the exposure to the safelight as short as possible.
Unwrapped films that are left too close to the safelight or exposed to the safelight for more than 2 to 3 minutes appear fogged.
A safelight must be placed a minimum of 4 feet away from the film and working area.
Types of Darkroom Lighting- cont’dTypes of Darkroom Lighting- cont’d
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Fig. 39-18 A minimum distance of 4 feet must exist between the safelight and the working area.Fig. 39-18 A minimum distance of 4 feet must exist between the safelight and the working area.
Fig. 39-18Fig. 39-18
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Processing Tanks Processing Tanks
Manual processing is a method that is used to develop, rinse, fix, and wash dental x-ray films.
The essential piece of equipment required for manual processing is a processing tank.
The processing tank is divided into compartments to hold the developer solution, water bath, and fixer solution.
A processing tank has two insert tanks and one master tank.
Manual processing is a method that is used to develop, rinse, fix, and wash dental x-ray films.
The essential piece of equipment required for manual processing is a processing tank.
The processing tank is divided into compartments to hold the developer solution, water bath, and fixer solution.
A processing tank has two insert tanks and one master tank.
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Fig. 39-19 Processing tanks showing developing and fixing tanks inserts in bath of running water. Fig. 39-19 Processing tanks showing developing and fixing tanks inserts in bath of running water.
Fig. 39-19Fig. 39-19
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Requirements for a Darkroom Requirements for a Darkroom
Be kept clean at all times. Infection control items (i.e. gloves,
disinfectant, spray, and paper towels). Container, labeled with a biohazard label, for
contaminated film packets or barriers. Recycle container for lead foil pieces; lead
foil should not be thrown in the trash. A “light-tight room.” Processing tanks for the developer and fixer
solution and a circulating water bath.
Be kept clean at all times. Infection control items (i.e. gloves,
disinfectant, spray, and paper towels). Container, labeled with a biohazard label, for
contaminated film packets or barriers. Recycle container for lead foil pieces; lead
foil should not be thrown in the trash. A “light-tight room.” Processing tanks for the developer and fixer
solution and a circulating water bath.
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Running water with mixing valves to adjust the temperature.
Both a safelight and a source of white (normal) light. An accurate timer. An accurate floating thermometer. Stirring rods or paddles to mix the chemicals and
equalize the temperature of the solutions. Safe storage space for chemicals. Film hangers. A film-drying rack and a film dryer.
Running water with mixing valves to adjust the temperature.
Both a safelight and a source of white (normal) light. An accurate timer. An accurate floating thermometer. Stirring rods or paddles to mix the chemicals and
equalize the temperature of the solutions. Safe storage space for chemicals. Film hangers. A film-drying rack and a film dryer.
Requirements for a Darkroom- cont’d Requirements for a Darkroom- cont’d
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Automatic Processor Automatic Processor
Automatic film processing is a fast and simple method used to process dental x-ray films.
Other than opening the film packet, the automatic processor automates all film processing steps.
Automatic film processing is a fast and simple method used to process dental x-ray films.
Other than opening the film packet, the automatic processor automates all film processing steps.
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Automatic film processing requires only 4 to 6
minutes to develop, fix, wash, and dry a film, whereas manual processing techniques require approximately 1 hour.
The automatic processor maintains the correct temperature of the solutions and adjusts the processing time.
Providing the automatic processor is maintained properly, there is less chance of errors during film processing.
Many dental offices that have automatic processors still maintain manual processing equipment as a stand-by if the automatic processor malfunctions.
Automatic film processing requires only 4 to 6 minutes to develop, fix, wash, and dry a film, whereas manual processing techniques require approximately 1 hour.
The automatic processor maintains the correct temperature of the solutions and adjusts the processing time.
Providing the automatic processor is maintained properly, there is less chance of errors during film processing.
Many dental offices that have automatic processors still maintain manual processing equipment as a stand-by if the automatic processor malfunctions.
Automatic Processor- cont’d Automatic Processor- cont’d
Copyright 2003, Elsevier Science (USA). All rights reserved.
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Components of the Automatic Processor Components of the Automatic Processor The processor housing covers all of the
component parts. The film feed slot is the the unwrapped films are
inserted into the automatic processor. The roller film transporter is a system of rollers
that rapidly moves the film through the compartments.
The developer and fixer compartments holds the solutions.The film is transported directly from the developer into the fixer without a rinsing step.
The water compartment holds circulating water. The drying chamber holds heated air and dries the
wet film.
The processor housing covers all of the component parts.
The film feed slot is the the unwrapped films are inserted into the automatic processor.
The roller film transporter is a system of rollers that rapidly moves the film through the compartments.
The developer and fixer compartments holds the solutions.The film is transported directly from the developer into the fixer without a rinsing step.
The water compartment holds circulating water. The drying chamber holds heated air and dries the
wet film.
Copyright 2003, Elsevier Science (USA). All rights reserved.
Fig. 39-20 Automatic film processing units provide rapid film processing.Fig. 39-20 Automatic film processing units provide rapid film processing.
Fig. 39-20Fig. 39-20
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Copyright 2003, Elsevier Science (USA). All rights reserved.
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Advantages of Automatic Film ProcessingAdvantages of Automatic Film Processing
Less processing time is required. Time and temperatures are automatically
controlled. Less equipment is used. Less space is required.
Less processing time is required. Time and temperatures are automatically
controlled. Less equipment is used. Less space is required.
Copyright 2003, Elsevier Science (USA). All rights reserved.
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Processing ErrorsProcessing Errors Processing errors may occur for a variety of
reasons, including: • Time and temperature errors (Table 39-4). • Chemical contamination errors (Table 39-
5). • Film handling errors (Table 39-6). • Lighting errors (Table 39-7).
The dental assistant must be able to recognize the appearance of common processing errors and know what to do to prevent the problem from occurring again.
Processing errors may occur for a variety of reasons, including: • Time and temperature errors (Table 39-4). • Chemical contamination errors (Table 39-
5). • Film handling errors (Table 39-6). • Lighting errors (Table 39-7).
The dental assistant must be able to recognize the appearance of common processing errors and know what to do to prevent the problem from occurring again.