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1 Dental Film X-ray Serves as a recording medium or image receptor. Images are recorded on the dental X-ray film when the film is exposed to a stimulus specifically energy in the form of x-radiation or light....

1 Dental Film X-ray Serves as a recording medium or image receptor. Images are recorded on the dental X-ray film when the film is exposed to a stimulus specifically energy in the form of x-radiation or light. X-ray Film Composition 4 Basic Components 1. Film Emulsion 2. Film Base 3. Adhesive layer Types of Dental X-ray Film 4. Protective layer 1. Extraoral Films 2. Intraoral Films Film Emulsion Is a coating attached to both sides of Dental X-ray Film: Extraoral Film the film base by the adhesive layer to Are films placed/ positioned outside give the film greater sensitivity to the mouth during x-ray exposure. x-radiation It Is used to examine large areas of the Film Base skull and jaws. Is a flexible piece of polyester plastic. constructed to withstand heat, moisture Extraoral Films and chemical exposure Example of Extraoral film Adhesive Layer Panoramic Films A thin layer of adhesive material that Cephalometric Films covers both sides of the film base. Serves as attachment of the emulsion Extraoral Film to the base. Protective Layer Is a thin, transparent coating placed over the emulsion. Serves to protect the emulsion surface from manipulation as well as mechanical and processing damage.  2 Cassette Film and Screen Film the Latin word apex meaning terminal end of a tooth root. Used to examine the entire tooth (crown and root) and supporting bone. 2. Bitewing film Used to examine the crowns of both the maxillary and mandibular teeth on the film With wing or tab attached to the tube side of the film 3. Occlusal Film Extraoral x-ray machine Used for examination of large areas of the maxilla or mandible Named occlusal because patient "occludes" or bites on the entire film Film is larger than a PA or bitewing films Dental X-ray Film: Intraoral Film 1. Periapical Film The term periapical is derived from the Greek word peri meaning around and  3 Parts of Dental X-ray Film 1. Outer package wrapping - Is a soft-vinyl or a paper wrapper that hermetically seals the film packet. - Serves to protect the film from exposure to light and saliva. 2. Paper Film wrapper - Is a protective sheet of black paper that covers the film. - Shields the film from light leak. 3. Lead foil sheet - Is a single thin piece of lead foil within the film packet that is located behind the film wrapped in black protective paper. - To shield the film from back scattered radiation that results in film fog. X-ray Film Processing Solution Developer Fixer  4 INTRODUCTION - Dental Radiographer: any History person who positions, exposes - Wilhem Conrad Roentgen and processes dental x-ray film. (November 8, 1895): Discovered the x-ray. Uses of Dental Radiographs - Dr. Otto Walkhoff (1896): German To detect lesions, diseases and dentist who made the 1st dental conditions of the teeth and surrounding use of x-ray by taking a structures that cannot be identified radiograph of a premolar (25 min clinically. exposure time) To confirm or classify suspected - Dr. Edmund Kells 1896: 1st diseases intraoral x-ray of a living patient To localize lesions or foreign objects - William Rollins: Developed the To provide information during dental 1st dental x-ray unit, procedures (e.g RCT) - William D. Coolidge: invented the To evaluate growth and development "hot cathode" xray tube. To illustrate changes secondary to - Victor Xray Corp/ General Electric caries, periodontal disease and trauma Xray Corp (1923): first dental To document the condition of a patient xray machine. at a specific point of time. - Eastman Kodak Company (1920): Manufactured the 1st pre-wrapped intraoral film in Properties of X-ray 1913. X-rays are produced by the conversion of electric energy into Terminologies radiation. - Radiation: a form of energy X-rays are invisible carried by waves or a stream of X-rays travel in straight lines particles. X-rays can penetrate opaque tissues - Radiology: the science or study and structures of radiation as used in medicine; X-rays can affect a photographic a branch of medical science that emulsion which when processed deals with the use of x-rays, produces a visible image. radioactive substances and other X-rays can adversely affect living forms of radiant energy in the tissue. diagnosis and treatment of disease. THE DENTAL X-RAY MACHINE - Radiograph: a picture/visible Parts and Components of the Dental photographic record on film X-ray Machine produced by the passage of x-rays through an object or body. - Dental Radiography: the making of radiographs of teeth and adjacent structures by the exposure of film to x-rays  5 Control Panel. Contains the regulating intensity of the beam exposure to devices. The components of the control be emitted. panel are switches, dials, gauges, and Vertical Adjustment Indicator lights. scale or indicator. Parts and Comonents of the Dental PID/BID. Device that allows the X-ray Machine beam to be aimed accurately at the area under investigation and also set up the focus-to-skin distance. Support Arm. Allows precise and steady positioning of the x-ray tube head so that the position indicating device may be aligned correctly. Tubehead. Contains x-ray tube where x-rays are generated Vertical Adjustment Indicator scale or indicator. Controls the  6 THREE STEP PROCESS OF X-RAY Yoke. By which the tube head is PRODUCTION attached to the extension arm First Step. that can revolve 360 degrees.. The first step in x-ray production is to turn on the machine. (If there is doubt on the part of the x-ray technician concerning the operation of the unit, reference should be made to the operator's manual.) When the unit is turned on, the filament of the cathode is heated Horizontal adjustment/pivot. by electrical current, causing it to Helps the movement and support emit electrons. of the headtube of the xray machine. Second Step For the second step, high voltage is passed across the x-ray tube. When this is done, the electrons or electron cloud from the filament are drawn across the opening toward the anode. The anode is made of tungsten and is sometimes called the tungsten target.  7 Third Step. The third and final step is the collision of electrons with the anode (tungsten target). This rapid deceleration of electrons produces x-rays, also referred to as photons. Figure, represents electrons striking the anode (tungsten target) and producing x-ray photons.  8 ERRORS OF DENTAL RADIOGRAPH Films with errors should be avoided due to the following reasons: Retake will lead to: 1. Expose the patient to unnecessary radiation 2. Waste film and time (money) 3. Interfere with accurate interpretation and diagnosis. FILM PLACEMENT ARTIFACTS Cause of faulty radiograph The majority of the errors produced can Patient preparation error be categorized into three groups: Blurred image 1. Technique & projection errors I. Technique and Projection errors Movement of the film, patient or x-ray II. Exposure errors tubehead during exposure will result in a III. Processing errors blurred image. A. Patient preparation error: Correction: the operator should explain Radiopaque for the patient and remind him to remain Blurred image motionless during exposure. B. Film placement artifacts: Double image Dot artifact Crown not shown Area of interest not shown Reversed film Apices cut off Double image Dropped film corner when an exposed film is re-exposed the Black line resulting film will have 2 superimposed images. c. Projection errors: Incorrect horizontal angulation PID alignment artifact Incorrect vertical angulation Patient preparation error Radiopaque Artifact - dental appliances, body piercings, Reversed film jewelry, eyeglasses left during exposure low density with herringbone, tire - track will appear as radiopaque artifact or dotted pattern, as a result of directing superimposed over the dental image.  9 the x-ray through the lead foil side of the film back. Projection errors Incorrect vertical angulation it will lead to: Elongated image due to insufficient vertical angulation (too flat) or  10 Shortened image due to excessive II. Exposure errors vertical angulation (too steep) Blank image Low density image High density image Image with high and low contrast III. Processing errors Chemical errors: ✓ Light image ✓ Dark image ✓ Blank image ✓ Reticulation ✓ Black spot or patch  11 ✓ White spot or patch ✓ Yellowish brown discoloration Film handling errors: ✓ Writing lines ✓ Developer cut off ✓ Fixer cut off ✓ Fingernail artifact ✓ Smudge ✓ Scratched film ✓ Static electricity FILM HANDLING ERROR 12 13