when was digital radiography introduced into dentistry?
1987
No ______ is required with digital radiography like film
processing
digital radiography produces what kind of image?
instant
what two things are used to in digital radiography?
electronic sensor and computerized imaging system
what is a radiographic image produced b conventional film
analog image
what is the number of possible gray scale combinations for each pixel
bit depth image
what is a solid state detector used in many devices, in digital radiography it is an image receptor found in the intraoral sensor?
charge-coupled device
filmless imaging system; a method of capturing a radiographic image using a sensor, breaking it into electronic pieces and presenting and storing the image using a computer
digital radiography
an image composed of pixels
digital image
one feature of digital radiography; a method of reversing the gray scale as an image is viewed; radiolucent images appear white and radiopaque images appear black?
digital subtraction
in digital radiography to convert an image into a digital form that in turn can be processed by a computer
digitize
method of obtaining a digital image in which an intraoral sensor is exposed to xrays to capture a radiographic image that can be viewed on a computer monitor
direct digital imaging
method of obtaining a digital image in which an existing radiograph is scanned and converted into a digital form using a CCD camera
indirect digital imaging
measurement used to evaluate the ability of the computer to capture the resolution of a radiographic image
line paires/millimeter (lp/ml)
a discrete unit of information. In digital electronic images, digital information is contained in and presented as discrete unites of information also termed picture element
pixel
in digital radiography a small detector that is placed intraorally to capture a radiographic image
sensor
method of obtaining a digital image in which the image is recorded on phosphor-coated plates and then placed into an electronic processor, where a laser scans the plate and produces an image on a computer screen
storage phosphor imaging
the purpose of digital radiography is to generate _____ that can be used in the _____ and _____ of dental disease
images
diagnosis
assessment
what are the uses for digital radiograph? (6)
detect lesions, disease and conditions of the teeth and surrounding structures
confirm or classify suspected disease
provide info during dental procedures
evaluate growth and development
illustrate changes secondary to caries, perio or trauma
document the condition of a patient at a specific point in time
In digital radiography a ____ is placed inside the mouth of the patient to capture the radiographic image
sensor
when the xray beam strikes the sensor what happens?
an electronic charge is produced on the surface of the sensor and the electronic signal is digitized and the sensor transmits the info to a computer in analog form and the computer converts it to digital form using an analog to digital converter and then the computer stores and displays the info within seconds
what kind of charge is produced on the sensor when the xray beam hits it?
electronic charge
what form does the sensor transmit the info to the computer?
analog form
what must the computer do to the info the sensor has given it?
convert it from analog to digital with a converter (ADC) and then store the image and display it
with digital radiography what is it called instead of a radiograph or xray film?
image
digital radiography is not limited to ______ images
intraoral
t/f digital radiography requires more x-radiation than conventional radiography
FALSE! sensor is more sensitive
the exposure times for digital radiography are what % less than conventional?
50 to 80%
____ impulses are used for digital radiography vs ____ for conventional
3 vs 12
with less exposure time the absorbed does to the patient is ____
lower (significantly)
what is the x-radiation source for digital radiography?
conventional dental xray unit
what must does the time frame need to be for digital?
1/100 of a second
t/f once the conventional unit has been altered for digital it can no longer be used as a conventional dental unit
FALSE! it can still be used for conventional
what are the three exxential components of a direct digital imaging system?
x-radiation source
intraoral sensor
computer
some sensors are _____, _____ and _____ but others mimic conventional film in their size and flexibility.
thick, bulky and rigid
what are the sensor sizes similar to?
size 0, 1, 2 and 4 intraoral films
intraoral sensors can be ____ (linked by a fiberoptic cable) or ____ (not linked by a cable)
wired
wireless
what are the three types of direct sensor technologies
charge-coupled device
complementary metal oxide semiconductor/active pixel sensor
charge injection device
what is one of hte most common image receptors used in dental digital radiography?
charge coupled device (CCD)
_____ _____ ______ uses special fabrication that is expensive to manufacture
charge coupled device
what other devices is CCD technology used in
fax machines
home video cameras
microscopes
telescopes
what type of direct sensor technology is a solid state detector that contains a silicon chip with an electronic circuit embedded in it
charge coupled device (CCD)
the silicon chip in CCD is sensitive to what?
x-rays or light
how are the electrons arranged on the silicon CCD
divided into ordered pizels (like silver crystals)
are the pixels for the CCD arranged randomly or ordered?
ordered
the CCD is ____ x ____ individual pixels in size
640 x 480
how many pixels does the CCD contain?
307,200
the CCD senses transmitted _____ and translates it into ______ message
light
electronic
what does the xray photon cause for the CCD?
electrons to be released from the silicon and to produce a corresponding charge
what does CMOS/APS stand for?
complementary metal oxide semiconductor/active pixel sensor
what manufacturer uses CMOS/APS?
Schick Technologies
what does Schick Technologies claim about CMOS/APS?
25% greater reolution
CMOS/APS claims to have _____% greater resolution
25%
the complementary metal oxide semiconductor/active pixel sensor (CMOS/APS) is ____ expensive to produce and offers _____ durability
less
greater
what does CID stand for?
Charge injection device
CID like CCD is what kind of receptor?
silicon based solid state imaging receptor
t/f no computer is required for charge injection device (CID)
true (its magic)
what is CID produced to work with?
reveal intraoral video camera docking platform
how are CID images viewed?
on the system monitor
CID pictures can be printed with a _____ _____ printer
color video
how can the pictures be saved with CID
on a computer file or a video disk recorder
what is the computer used for with digital radiography?
used to store incoming electronic signals
converts the electronic signal from sensor into a shade of gray
what does the computer convert the electronic signal into?
shade of gray
where are digital images viewed with a computer?
computer monitor
how are the pixels represented on the computer?
mumerically by location and level of color of gray
what is the range of numbers for pixels?
varies from 0-255
how many shades of gray do the pixels show?
256
how many shades of gray can the human eye see?
32
what is the gray scale resolution?
0-255 pixel range totaling in 256 shades of gray
the number of possible gray scale combinations per pixel is known as?
bit-depth image
what does the computer software allow?
manipulation of pixels (enhancing contrast density)
t/f software requires more radiation exposure to the patient
FALSE! it allows for manipulation of pixels without additional exposure to patient
the computer ____, ____ and stores information received from the ____
digitizes
processes
sensor
the image is viewed on the monitor in ____ to ____ seconds
.5-120 seconds
the computer allows for a magnification of ___x
4x
what measurements can be made from the image on the monitor?
linear and angular measurements
what allows for the operator to view and compare multiple images on the same screen?
split screen technology
what equipment is needed for direct digital imaging?
xray machine
intraoral sensor
computer monitor
what are the components needed for indirect digital imaging?
CCD camera and compouter
t/f indirect digital imaging is not as good of quality as direct digital imaging
True!!
what is a second type of indirect digital imaging?
storage phosphor imaging
is storage phosphor imaging wired or wireless
wireless
what does storage phosphor imaging use instead of a sensor?
reusable imaging plate coated with phosphors
what is the storage phosphor plate similar to?
intensifying screens
how is the image cleared from a storage phosphor plate?
light
how are storage phosphor plates digitized?
high speed scanner converts information into electronic files
how long does the extra step of scanning during storage phosphor imaging take?
30 to 5 min
what must the sensor be covered with before use? why?
disposable barrier
it cannot be sterilized
what guidelines should you follow when taking digital radiography?
manufacturers recommendations
what is the preferred exposure method for digital radiography, why?
paralleling technique
for dimensional accuracy of images and ease of standardizing such images
why must film holders be used for digital radiography?
