Ch 8: Digital Imaging

1.    Digital imaging uses _________________ to produce an image.

• processing chemistry

• an electronic sensor and computerized imaging system

• radiographic film

• an x-ray processor

1. With digital imaging, the term ___________ is used to describe the pictures that are produced.

• radiograph

• x-ray film

• image

• phosphor

1. Your patient is concerned about the amount of x-ray exposure she has had because she had x-rays taken quite often at her previous dental office. You explain to her that the images are necessary and you will be taking digital images which require exposure times that are ________ than that required for conventional film-based radiography.

• 70% to 100% less

• 50% to 90% less

• 20% to 50% less

• 10% to 20% less

1. Most digital imaging systems use a ______________ as the x-radiation source.

• flat-bed scanner

• conventional dental x-ray unit

• commercial analog intraoral camera

• commercial digital intraoral camera

1. In order to be used for digital imaging, the x-ray unit timer must be adapted to allow exposures in a time frame of _______ of a second.

• 1/5

• 1/10

• 1/15

• 1/100

1. How many shades of gray can the human eye distinguish?

• 16

• 32

• 64

• 256

1. The images are cleared from the photo-stimulable phosphor (PSP) imaging plates by

• being processed in an x-ray processing machine.

• a clearing step within the scanner.

• being exposed to viewbox light for several minutes.

• being placed in a microwave oven for 1 minute.

1. Your patient has asked why you prefer digital imaging to film. Which of the following reasons would you tell her?

• The sensors can be autoclaved and reused.

• The image appears almost instantaneously for both of us to view.

• The images appear in color instead of black and white.

• The initial setup costs were lower than it cost to set up film.

1. (1) A primary advantage to digital imaging is the superior gray-scale resolution that results. (2) Digital imaging uses up to 32 shades of gray.

• Both statements are true.

• Both statements are false.

• The first statement is true; the second statement is false.

• The first statement is false; the second statement is true.

1. Digital imaging manufacturers maintain a range of 6 to 22 line pairs/millimeter (lp/mm) and the human eye can recognize about __ lp/mm.

• 2

• 4

• 8

• 16