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x-rayfilmtypesindications-221026152127-4213f1ff.pdf

Biomedical
19 Mar 2023
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x-rayfilmtypesindications-221026152127-4213f1ff.pdf

  1. By : Maryam Mageed Nife Nakheel Moaied Raheem Masoma Mohammed Jaseem Mohammed Zaki Habib Mohammed Kareem Radhi X-Ray Film (Types & Indications)
  2. X-ray films are the most widely used receptor system in dentistry. This presentation will describes x-ray films composition , types , sizes and indications. Introduction
  3. Extra oral X- Ray film Contents X-Ray Film Composition Intraoral X-Ray Film
  4. X-Ray Film Composition X-ray film has two principal components: 1- Emulsion 2- Base Emulsion The two principal components of emulsion are silver halide grains, which are sensitive to x-radiation and visible light, and a vehicle gelatinous matrix in which the crystals are suspended.
  5. Scanning electron micrograph of emulsion of INSIGHT film showing flat tabular silver bromide crystals, Scanning electron micrograph of INSIGHT dental x-ray film
  6. Emulsion The silver halide grains are composed primarily of crystals of silver bromide. The silver halide grains in INSIGHT film and Ultra-speed film are flat, tabular crystals with a mean diameter of approximately 1.8 μm The tabular grains are oriented parallel with the film surface to offer a large cross-sectional area to the x-ray beam. INSIGHT film has approximately twice the number of silver grains so that it requires only half the exposure of Ultra-speed film.
  7. Base The function of the film base is to support the emulsion. The base for dental Xray film is made of polyester polyethylene terephthalate, which provides the proper degree of flexibility to allow easy handling of the film.
  8. Base The film base must also withstand exposure to processing solutions without becoming distorted. The base is uniformly translucent and casts no pattern on the resultant radiograph.
  9. . 1- Intra oral X- Ray film 2- Extra oral X- Ray film Types of X-Ray Film
  10. Intraoral X-Ray Film Intraoral dental x-ray film is made as a double-emulsion film (i.e., both sides of the base are coated with an emulsion). With a double layer of emulsion, less radiation is required to produce an image.
  11. Intraoral X-Ray Film Direct exposure film is used for intraoral examinations because it provides higher resolution images than screen-film combinations. Some diagnostic tasks, such as detection of incipient caries or early periapical disease, require this higher resolution.
  12. One corner of each dental film has a small, raised dot that is used for film orientation (A) The raised film dot (arrow) indicates the tube side of the film and identifies the patient's right and left sides. (B) The location of this dot is clearly marked with a black circle on the outside of every film packet.
  13. 01 A thin lead foil backing with an embossed pattern is between the wrappers in the film packet. The foil is positioned in the film packet behind the film away from the tube. This lead foil serves several purposes such as : 1- It shields the film from backscatter (secondary) radiation, which fogs the film and reduces image contrast (image quality). 2- It reduces patient exposure by absorbing some of the residual x-ray beam.
  14. 01
  15. Types of Intraoral X-Rays film Periapical View ( Type I) Periapical views record the crowns, roots, and surrounding bone. Film packs come in three sizes • Size 0 for small children (22 mm × 35 mm) • Size 1, which is relatively narrow and used for views of the anterior teeth (24 mm × 40 mm) • Size 2, the standard film size used for adults (30.5 mm × 40.5 mm)
  16. Bite-Wing View ( Type II) Bite-wing (interproximal) views record the coronal portions of the maxillary and mandibular teeth in one image. They are used to detect interproximal caries and evaluate the height of alveolar bone. Size 2 film is normally used in adults; the smaller size 1 is preferred in children. In small children, size 0 may be used. A relatively long size 3 is also available.
  17. Bite-Wing View ( Type II) Bite-wing films often have a paper tab projecting from the middle of the film on which the patient bites to support the film. This tab is rarely visualized on the image and does not interfere with the diagnostic quality of the image. Film-holding instruments for bite-wing projections also are available.
  18. Occlusal View ( Type III) Occlusal film, size 4, is more than 3 times larger than size 2 film. It is used to show larger areas of the maxilla or mandible than may be seen on a periapical film. These films also are used to obtain right-angle views to the usual periapical view. The name derives from the fact that the film is held in position by having the patient bite lightly on it to support it between the occlusal surfaces of the teeth
  19. Extra oral X- Ray film The purpose of using such film is to make a radiographic image able to examine an area in and around the jaw that can't be seen by intra oral film, there are two types of extra oral film : 1- Non screen film 2- screen film
  20. Non screen film 1. Film emulsion is more sensitive to X- ray than to light. 2. The film has double emulsion like intra oral film but the emulsion is thicker. 3. Increased thickness of emulsion make the non screen film need less amount of radiation so it need less exposure time. 4. The size of the film used include: 5×7 and 8×10 inches.
  21. Screen film 1. Film emulsion is more sensitive to visible light and more specifically to blue light in the visible light spectrum. 2. The size include: - 5×7, 8×10 and 10×12 inches. 3. Screen film has 3 types:- slow or detail screen, medium or par – speed screen and fast or high – speed screen. 4 .The screen film placed between 2 fluorescent screen in cassette. These 2 fluorescent screen made from (tiny calcium tungestate crystals). When these crystals exposed to X- Ray , the result of this exposure is a creation of light , this light in turn exposes the screen film to produce the image.
  22. Cassette for 8-Inch × 10-Inch Film Along With a Sheet of Screen Film
  23. 01 The extraoral projections used most frequently in dentistry are panoramic and cephalometric views For these projections, screen film is used with intensifying screens to reduce patient exposure Screen film is different from dental intraoral film. is designed to be sensitive to visible light because it is placed between two intensifying screens when an exposure is made.
  24. 01 The intensifying screens absorb x-rays and emit visible light, which exposes the film. Silver halide crystals are inherently sensitive to ultraviolet (UV) and blue light (300 to 500 nm) and thus are sensitive to screens that emit UV and blue light.
  25. 01 When film is used with screens that emit green light the silver halide crystals are coated with sensitizing dyes to increase absorption. It is important to use the appropriate screen-film combination recommended by the screen and film manufacturer
  26. Thanks For listening
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