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FILM
PROCESSING GUIDELINES FOR DENTAL X-RAY SYST
The quality of
the radiograph will be adversely affected by various light and processing
factors. The suggestions below are provided to help identify and correct
these potential problems.
THE
FILM
The Clear Image™ OGA (like Kodak's TMAT-G) film recommended for
use with the latest ISI Wicor 400 speed Rare Earth, Dr. Goos® Graduated
or Lanex Regular Intensifying Screens is green-light sensitive and as
such, is far more light sensitive than both conventional intra-oral
and blue-light (RP) sensitive film. In addition, all film exposed to
radiation is eight to ten times more sensitive to white light leaks
and further radiation than unexposed film.
THE
DARKROOM
The darkroom must be 100% LIGHT TIGHT. Apply self-adhesive weatherstripping
around ALL door, ceiling and light fixtures emitting white light. Walls
may be painted any light pastel color.
THE
SAFELIGHT
The filter must be a Type GBX with a 15 watt frosted light bulb or Imaging
Systems' GBX Fluorescent Safelight. A 6-B, ML-1 or ML-2 filter with
a 7.5 or 15 watt bulb is UNACCEPTABLE and will fog (darken) green sensitive
extra-oral film. Imaging Systems' GBX Fluorescent Safelight is recommended
offering over 68% more illumination than the above conventional combinations
and is safe for all film. All safelights must be mounted a minimum of
4 feet from the working surface.
MANUAL PROCESSING
Use
only Kodak GBX developer and fixer. DO NOT agitate film during development
to expedite processing, but do AGITATE PERIODICALLY throughout the day
to mix the chemicals. Process as follows:
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Temp of Solution
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Dev. Time
|
Rinse
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Fix
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Final Wash in Water
|
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60°F
(15.5C)
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8.5 min.
|
30
sec.
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4 min.
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20 minutes
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65°F
(18.5C)
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6 min.
|
"
|
"
|
"
|
|
68°F
(20.0C)
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5 min.
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"
|
"
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(68°
optimum)
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70°F
(21.0C)
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4.5 min.
|
"
|
"
|
"
|
|
75°F
(24.0C)
|
3.5 min.
|
"
|
"
|
"
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Note: The above schedule
is for Clear Image™ OGA, Clear Image™ RP, Kodak BB, Ektamat
G and Duplicating film only. Add 2 minutes to developing times when using
X-OMAT RP. Add 3 minutes to developing times when using any of the T-MAT
series film. MAX.
SOLUTION LIFE IS 7 DAYS. REPLENISH 1.5 oz. PER EXTRA-ORAL FILM.
AUTOMATIC PROCESSING
A 5.5 minute dry to
dry cycle is mandatory for archival quality when using any of the common
"Dental" brand chemistries. Due to the increased strength of Imaging Systems'
"Medical" AUTOCHEM PREMIXED Chemistry, your time cycle may be reduced
to 4.5 minutes for a further time savings over the "Dental" brands.CONFIRM
the manufacturer's recommended developer temperature with an accurate
thermometer. (For the Philips 810, XL, Dent-X, Hope and A/T 2000, use
82-83°F (28.3°C). For optimum results, use only Imaging Systems'
AUTOCHEM PREMIXED darkroom chemistry and Imaging Systems' Clear Image™
Film.Note: Instructions for changing from Brand X to IMAGING SYSTEMS'
AUTOCHEM PRE-MIXED developer and fixer.
a. COMPLETELY
drain and flush out all 3 reservoirs, replenishment bottles and lines
with hot water. b.
Soak each transport assembly a minimum of 30 minutes in separate hot
water baths.
Caution: The older
the processor, the more comprehensive the cleaning procedure must be as
the older neoprene rollers have absorbed a greater amount of solution.
Just 2cc's of residual solution will contaminate the new chemistry. It
is not unusual for the first mix of AutoChem or Kodak to be less than
ideal particularly in cases where the neoprene has broken down and absorbed
greater amounts of developer.
WEEKLY MAINTENANCE
1. At the start
of each work week, drain the solutions, remove and soak all 3 transports
in separate hot water baths for 20-30 minutes. Use individually labeled
dish pans to prevent cross-contamination.
- DO NOT USE ANY
CLEANING AGENTS OR DETERGENTS on the transport assemblies. All, including
those recommended by the manufacturer, will leave deposits and contaminate
the developer solution.
- Do not alternate
transport assemblies. Never place the fixer transport in the developer
section and vice versa.
- Do not allow
the transport assemblies to dry. This will result in premature destruction
of the neoprene.
- Remove any crystalline
and/or gummy deposits with a fingernail brush or equivalent.
2. Following
the 20-30 minute soak in hot water, add fresh solutions (ALWAYS FILL THE
FIXER COMPARTMENT FIRST), reinstall the transport assemblies and immediately
run a fresh clean-up film (Kodak Roller Transport Clean-up film: 8x10
#114-1530) through to pick up the dislodged debris. Once a clean-up film
has been run through 3 or more times, it is nothing more than a piece
of mylar and has no further clean-up properties.3. The maximum
solution life is 7 DAYS WITH REPLENISHMENT. In systems without automatic
replenishment, replenish 1.5 oz. developer and fixer per extra-oral film
or periapical equivalency. Record each processed extra-oral film on a
calender situated on the darkroom wall. Total each days production, multiply
by 1.5 for rates. Drain out the required amount of both developer and
fixer (a min. of 10 oz. per day) and bring the fresh developer and fixer
up to their recommended levels. For systems with automatic replenishment,
merely add to the replenishment bottles each month-discard only if the
chemistry has discolored.4. A radiograph swells a specific percentage
as it absorbs developer in a controlled environment. When using a solution
other than AutoChem and at a cycle of less than 5.5 minutes, a radiograph
will absorb excess developer and swell to a dimension that is now too
thick to adequately clear the "squeegee" rollers, potentially inducing
processor mechanical problems and causing "roller marks".5. Contrary
to many unfounded claims, THE USE OF IMAGING SYSTEMS' AUTOCHEM PREMIXED
(or any other mfgr's chemistry!) WILL NOT "GUM UP" THE ROLLERS NOR VOID
THE MANUFACTURER'S WARRANTY. 6.
The above recommendations will assure archival quality processing and
results within acceptable exposure guidelines. In most instances, the
above technique will also allow the clinician to reduce their exposure
rates 20-30% with a subsequent increase in detail and resolution.
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