After the patient has been radiographed, the X-ray film is processed to produce the finished radiographs. There are five basic steps involved in processing X-ray film: developing, rinsing, fixing, washing, and drying. You can process the film manually, or use an automatic film processor. For the most part, manual processing is used for a backup method for the automatic film processor and will not be discussed. If your command has manual processing capabilities, refer to the manufacturer's operating instructions. Because our discussion concerns both darkroom procedures and film processing, we will cover the darkroom first.
The darkroom has two sources of illumination: white light and safelight. A white light is a standard ceiling light. It provides regular illumination for mixing solutions and cleaning the darkroom. An unwrapped, unprocessed X-ray film must never be exposed to white light.
Exposed film is useless. A safelight, which contains a 15 watt bulb with a special filter, is the only safe source of illumination in the darkroom when processing intraoral and panoramic X-ray film. The safelight must be located no less than 4 feet from the work surface so that you can open film packets and process films safely. Limit the length of exposure of undeveloped dental films to the safelight for no more than 2 minutes. Films left out exceeding this time might get a fogged image (discussed under faulty radiographs).
Occasionally, films are ruined because of light leakage. White light may leak through the filter on the safelight or it may leak into the darkroom from an outside source. A simple test will enable you to detect leakage.
To check for possible light leakage from an outside source, perform the test with all lights off, including the safelight.
Take a packet of unexposed X-ray film, open the film packet, and remove the film. Lay the film on the workbench, and place a penny over it for a period of 5 minutes. Then, process the film using the procedures provided later in this chapter. The processed film should show no image. If the outline of the penny can be seen, there is light leakage and you should inform your supervisor. You should perform this test at every location in the darkroom where unwrapped film is being processed.
Because of the alkaline and acid nature of the developer and fixer solutions, minor chemical irritation or burns can occur when they come in contact with the skin, the eyes, and the mouth. Use caution when stirring or mixing solutions. Always wear rubber gloves and protective eye wear or a protective face shield and an apron when working around these solutions. If the solutions come in contact with the skin, flush the area with large amounts of water. If the solutions accidentally splash into the eyes or mouth, flush with large amounts of water and immediately seek medical attention. Fixer solution can stain and discolor clothing.
Automatic processing is the most commonly used method of processing dental radiographs in the Navy. The automatic film processor mechanically transports exposed X-ray film through the developing, fixing, washing, and drying cycles. Automatic processing is quicker than manual processing, and it produces finished radiographs of uniform quality. A variety of automatic film processors are in use in the Navy and they can be generally classified as small or large.
The large automatic processor (fig. 1-44) processes all sizes of dental radiographs including intraoral, occlusal, panoramic, and 8-inch x 10-inch cephalometric films.
This processor will be located in the darkroom. The X-ray film must be inserted in the processor under safelight conditions. Large automatic processors can be equipped with daylight loaders, eliminating the need for a darkroom.
Perform the operational check at the beginning of each day to ensure that the processor is in good working order. It is a complex piece of equipment, so read the manufacturer's operational manual very carefully. Never attempt to repair the components inside the processor. There are a variety of large automatic processors used in the Navy today. The automatic processor's components, procedures, andContinue Reading