Exam III Schtuff Flashcards
(45 cards)
What is the most important advantage of digital X-rays over film?
DOSE REDUCTION!
What is the bit depth of our digital x rays?
2^8…256 gray levels
Physical Characteristics: What is the term for how much DETAIL you can see in a digital x ray?
SPATIAL RESOLUTION
Physical Characteristics: Spatial Resolution is a term for how much _____ you can see in a digital x-ray.
DETAIL
Physical Characteristics: _______ is how many SHADES OF GRAY are available for the digital x-ray…
CONTRAST RESOLUTION
Contrast Resolution: how many ________ are available for the image?
SHADES OF GRAY
What is basically the ONLY characteristic where film beats digital?
resolution
Pros and Cons: Solid State Receptor-it is ______ as opposed to indirect..Unfortunately it has large _______, there is a ______ attached, it has a SMALL exposure _______, and it is EXPENSIVE!!
direct….dimensions….cable….small exposure LATITUDE
Pros and Cons…PSP sensors- unfortunately they are ______ instead of direct..the plates can get ______ over time…its good that its like a film and has a LARGE exposure _______ and they are CHEAP!
indirect….scratched….Large exposure LATITUDE (a good thing!)
***Which feature of x-rays IS NOT that important for detecting dentoalveolar disease??
RESOLUTION (most systems have MORE resolution than the human eye can detect)
**What are the two most important characteristics of an x-ray that play a large role in detecting dentoalveolar disease?
contrast and density
What is the anatomical name for a WATERS view x ray?
Occipito-Mental Projection
Which x-ray projection does the patient open their mouth as wide as possible while the x-rays are being emitted from behind them? What is an indication of this x-ray?
Reverse-Towne Projection…condylar fracture
What does a SMV projection stand for? What is the most common indication for this view?
Sub-Mento-Vertex Projection…zygomatic fracture
Which projection can give a nice lateral view of the mandible/head and neck?
Mandibular/Lateral OBLIQUE projection
For a PANO- what are the anatomical objects considered to to be in the FOCAL PLANE/FOCAL TROUGH of the film?
Teeth/Jaw
***In a PANO, you will get MAGNIFICATION of your image if the object you are imaging is ________ to the focal trough!
POSTERIOR
***In a PANO, you will get MINIFICATION of your image if the object you are imaging is ________ to the focal trough!
ANTERIOR
When looking at the jaw from a superior view, what is the most common area that produces double images?
A diamond shaped area posterior to the anterior mandubilar teeth and ending at the anterior of C1
When looking at the jaw from a superior view, what is the most common area that produces Ghost images?
A half circle area with a pointed tip in the anterior. It begins just behind the anterior mandibular teeth and then spreads out to cover all of the posterior structures (ramus,hyoid, C1)
You will get an extremely UP CURVED smile in your PANO if the patient has an excessive ________ chin tip at the time of exposure…
DOWNWARD
You will get an extremely DOWN CURVED smile in your PANO if the patient has an excessive ________ chin tip at the time of exposure…
UPWARD
What is the #1 PANO artifact due from? What is the main flag that tells you what happened in this casE?
Patient Swallowing during exposure…the hypoid bone is elevated!
DID YOU KNOW, a study found that only ___% of PANO’s were accurate plus or minus 1 mm???!!!
17%
