chapter 39: Dental imaging, dental film, and processing radiographs

What year was the introduction of digital radiography

1987

What are the types of dental images

Periapical, bite wing, occlusal

What is the fastest film speed

F-speed

Why is F speed so fast

The emulsion is thick and the crystals are larger

F-speed reduces radiation exposure to patient by how much

20%-60%

What are the types of film

intraoral film, duplicating film and extraoral film

Composition of dental x ray film

Film base, silver emulsion, adhesive, gelatin, protective layer

Care and maintenance for processing solutions

Replenished daily and replaced every 2-3 weeks

Dental film sizes

0,1,2,3,4

Size #0

children younger than 3 years

Size #1

For children & adult anterior PA

Size #2

Adult size & occlusal for children

Size #3

Adult bite wings

Size #4

Occlusal

Purpose of intensifying screen

reduces the radiation dose to patient while still providing a high quality image

Direct digital image

Digital sensor [dir-indirect]

Indicrect digital image

Phosphor storage plates (PSP) [dir-indirect]

latent image

The image on a film before it is processed

Types of extraoral film cassette

Flexible and rigid

What converts x-ray energy into light

Intensifying screen

What is a digital sensor made of

silicon chip

What used to position and hold film or the digital sensor in the patient’s mouth

Positioning instruments

Example of a positioning instrument

Eezee-Grip Sensor holder

Example of a beam alignment device

Rinn XCP and Rinn XCP-DS with color-coded plastic bite-blocks, rings, and metal arms

Where should the identification dot be facing when film is in the holder?

That should be facing the slot

What is inside a intraoral film packet

The lead foil sheet, the film and black protective paper

most common extraoral films

panoramic and cephalometric films

types of screen film used in extraoral radiography

Blue and Green-sensitive film

Green-sensitive film is used with cassettes with intensifying screens

rare earth (sensitive film)

Blue-sensitive film is used with cassettes with what intensifying screens

calcium tungstate (sensitive film)

What film is used only in a darkroom setting and is never exposed to x-rays

Duplicating film (used)

steps in film processing

developer, rinsing, fixing solution, washing and drying

Film processing solutions forms

powder, ready-to-use liquid, and liquid concentrate

What is necessary in a darkroom

a safelight, adequate working space and good ventilation

Inadequate development time causes

Underdeveloped film (Light)

Excessive developing time causes

Overdeveloped film (Dark)

Sudden temperature change between developer and water bath causes

Reticulation (cracking)

What error happens when film pack is opened quickly during manual processing

Static electricity ( thin, black branching lines)

Developer contacts film before processing causes

black spots (errors)

Fixer contacts film before processing causes

White spots (errors)

expired film causes

Fogged film

What is the tube side of film?

The white side

What side of the film is the label side?

The colored side

What side of the cassette faces the patient

The front side

What can happen to can happen to cassette if not cared for properly

It can get scratched, leaving streaks on film

What setting is duplicating film is used in

A darkroom

What should film be protected from

Light, heat, moisture, chemicals and scatter radiation

Film processing solution must be replenished

Daily

Film processing solution must be changed

3-4 weeks

How far away should the safelight be placed from film and working area

4 feet

What is the optimum temperature for the water bath

68 degrees

How long does the automatic film processing take to develop?

4-6 minutes

Levels of solutions in the automatic processor are to be checked how often

beginning of each day and replenished

How long should automatic processor be replaced

every 2 to 6 weeks