EX1; Radiographic Film and Types of Radiographs Used in Dentistry

Question 1

What are the two main components of radiographic film

Answer 1

base

emulsion

Question 2

What comprises/properties of the base of radiographic film

Answer 2

polyester
supports emulsion
flexible (to allow film handling)
translucent
chemically inert
tinted blue to enhance contrast

Question 3

What is the richness of the base of radiographic film

Answer 3

0.125-0.225mm

Question 4

What comprises the emulsion of radiographic film

Answer 4

silver nitrate and potassium bromide in gelatin to form AgBr crystals

Question 5

What is added to the emulsion to increase sensitivity

Answer 5

potassium iodide and a trace amount of silver sulfide

Question 6

True or False

The emulsion is only coated on one side of the base

Answer 6

False; it is coated on both sides of the base

Question 7

When does an image form in emulsion

Answer 7

when it is exposed to X-rays or light

Question 8

How does the emulsion form the latent image

Answer 8

the AgBr in the emulsion forms metallic silver when exposed to X-rays, then the metallic silver is chemically processed to form a radiograph

Question 9

This is radiographic density produced by causes/sources other than the primary beam of radiation reducing the radiographic contrast

Answer 9

radiographic fog

Question 10

This is due to AgBr crystals made developable by catalytic action of contaminants in the emulsion

Answer 10

emulsion fog

Question 11

This is due to development of unexposed AgBr crystals due to impurities in the developer solution

Answer 11

chemical fog

Question 12

This is due to exposure of film by scatter radiation; it is the most common type of fog

Answer 12

scatter radiation fog

Question 13

This is due to exposure of film by an unsafe light

Answer 13

safelight fog

Question 14

Which type of radiographic fog is easily avoided

Answer 14

safelight fog

Question 15

This is the ability of a film to produce certain radiographic density with lesser or greater amount of radiation

Answer 15

speed

Question 16

A higher speed film requires what

Answer 16

less radiation (and a lower speed file requires more radiation)

Question 17

What is the main advantage of higher speed film

Answer 17

substantially reduced patient exposure

Question 18

What is the main disadvantage of higher speed film

Answer 18

less image sharpness due to larger size of the AgBr crystals

Question 19

Which film type is the fastest

Answer 19

F

Question 20

This is the ability to record separate images of very small objects placed very close together

Answer 20

resolution

Question 21

What is the resolution of intraoral films

Answer 21

more than 20 line pairs/mm

Question 22

What is the resolution of intraoral sensor

Answer 22

25 line pairs/mm

Question 23

This is used to intensity photographic effect of X-rays by converting them to visible light; reducing radiation exposure of patients by 10-60 times

Answer 23

intensifying screen

Question 24

This makes up the intensifying screen

Answer 24

phosphol layer

Question 25

What are the cassettes for intensifying screens used for

Answer 25

holders for the screen

Question 26

What is the intensification factor

Answer 26

10; | 10 times less radiation to patient

Question 27

What is the difference in using rare-earth screens

Answer 27

they have an intensifying factor of 40-60

Question 28

What are the types of intra oral films (and the number represented)

Answer 28

``` 1 = periapical 2 = bitewing 3 = occlusal ```

Question 29

What are the different sizes of intraoral films

Answer 29

0 (smallest), 1, 2, 3, 4 (largest)

Question 30

What are the standard sizes of intraoral films

Answer 30

periapical = 1.2 bitewing = 2.2 occlusal - 3.4

Question 31

What is the largest bitewing film

Answer 31

3; it is longer

Question 32

What is important to capture when taking a periodical radiograph

Answer 32

the root, the entire crown is also preferred but teeth with long roots may have to sacrifice seeing the crown

Question 33

What are the two techniques for taking periapical radiographs

Answer 33

``` parallel bisecting angle (long axis) ```

Question 34

What does a bitewing record

Answer 34

crowns of maxillary and mandibular teeth and alveolar crest

Question 35

What is a bitewing used to assess for

Answer 35

alveolar crest defects; marginal periodontal bone loss | caries

Question 36

This is used for assessing anterior jaw and associated dentition

Answer 36

topographic occlusal

Question 37

This is used to assessing whole body of jaw

Answer 37

cross-sectional occlusal

Question 38

In which occlusal radiograph does the beam have to penetrate the nasal cavity

Answer 38

topographic

Question 39

In which occlusal radiograph does the beam have to penetrate the frontal bone, orbital region, etc.

Answer 39

cross-sectional

Question 40

When is the best time to use an extra-oral radiograph

Answer 40

when the area to be imaged is larger than could be covered by an intraoral image receptor or pathological process located in an area not covered by an intraoral