Ch. 39 Radiography Equipment (1)
What are the five different sizes of intra-oral films?
0, 1, 2, 3, 4
What is the fastest speed of film and why?
F speed, the fast film responds more quickly because the silver halide crystals in the emulsion are larger.
What films make up a full mouth survey, numbers and types?
4 BW's, 6 anterior size 1 PA's, and 8 size 2 posterior PA's
Why do we use occlusal films?
Supernumerary teeth, eruption patterns, anterior trauma.
What are the three types of intra-oral films?
Periapical, Bitewings, and Occlusal
When storing dental film, what conditions need to be met?
Cool, dry, dark, and away from scatter radiation.
What are the advantages of bitewings?
See interproximal decay and crestal bone levels, and easy to use
What size of occlusal film is used for adults?
Size 4
What is the composition of x-ray films?
4 basic components: film base, adhesive layer, film emulsion layer, and protective layer
What is the difference between vertical and horizontal?
Vertical: calculus and bone loss
Horizontal: decay
What size film is used for a pediatric occlusal x-ray?
Size 2
Describe the bisecting technique.
Places the film directly against the teeth, making the film and the teeth not parallel, but at an angle.
What techniques can be used to duplicate films?
Duplicating film is used only in a darkroom setting and is never exposed to x-rays. The duplicating machine produces white light to expose the film. Because the film is light sensitive, the duplication process is performed in the darkroom with the safelight.
List the 5 basic rules for paralleling technique.
Receptor is placed to cover specific teeth, receptor is placed parallel to the long axis of the tooth, teeth are parallel to the PID, horizontal angulation- direct central rays through the contact of teeth. X-ray beam is directed into the center of the receptor.