Presentation on theme: "TECHNIQUE/PROCESSING ERRORS TERMINOLOGY DA 118. RADIOLUCENT Terms used to describe the black areas and white areas viewed on a dental radiograph are radiolucent."— Presentation transcript:
RADIOLUCENT Terms used to describe the black areas and white areas viewed on a dental radiograph are radiolucent and radiopaque. - RADIOLUCENT: portion of a processed radiograph that is dark or black; e.g., air space freely permits passage of dental x-rays and appears radiolucent on a dental radiograph. Air space (arrow) appears radiolucent, or dark, because the dental x-rays pass through freely.
RADIOPAQUE RADIOPAQUE: portion of a processed radiograph that appears light or white; e.g., structures that resist passage of x-ray beam- enamel, dentin and bone appear radiopaque on a dental radiograph. Dense structures, such as enamel (1), dentin (2), and bone (3), resist the passage of x-rays and appear radiopaque, or white.
LATENT IMAGE LATENT IMAGE FORMATION: silver halide crystals absorb x-radiation during x-ray exposure and store the energy from the radiation. - The stored energy within the silver halide crystals forms a pattern and creates an invisible image within the emulsion on the exposed film. - This pattern of stored energy on the exposed film cannot be seen and is referred to as latent image.
FORESHORTENED Foreshortened images: images that appear shorter than the actual length of the teeth. - Teeth appear short with blunted roots on the image - occurs due to excessive vertical angulation
ELONGATED IMAGES Elongated images: images that appear longer than the actual length of the teeth. - Teeth appear long and distorted on the image - occurs when vertical angulation is insufficient
HORIZONTAL AND VERTICAL ANGULATION Horizontal angulation: The positioning of the position - indicating device (PID) and direction of the central ray in a horizontal or side-to-side plane.
HORIZONTAL AND VERTICAL ANGULATION Vertical angulation: The positioning of the position - indicating device (PID) in a vertical or up and down plane.
CONE-CUT CONE-CUT: A clear, unexposed area on a dental radiograph that occurs when the position -indicating device (PID) is misaligned and the x-ray beam is not centered over the film.