61 97 102 D3495
D3495
.
201.03.07
.
02 08.2011
27
Sirona Dental Systems GmbH
6
Exposure times
Operating Instructions XIOS
Plus
Sensors
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6
Exposure times
Exposure times
Explanation
The dose to be set for X-ray exposure depends primarily on the following:
● Type of X-ray tube assembly (manufacturer, AC/DC, etc.),
● Distance between beam focus and sensor,
● Morphology of patient,
● Object (i.e. tooth), which is to be X-rayed.
The dose is adjusted through tube voltage and tube current (specified by
kV/mA) as well as exposure time.
The X-ray dose influences the image quality that can be achieved by an
X-ray system. Based on fundamental laws of physics, with digital X-ray
sensors - as with film - an insufficient dose generally means higher image
noise, which usually leads to poorer detail discrimination.
On the other hand, a too-high dose can cause the sensor to be
overexposed. This is noticeable by a decreasing detail discrimination,
specifically in darker areas.
Brightness and contrast can always be optimally adjusted through the
XIOS
Plus
image preprocessing function, independent of dose.
XIOS
Plus
sensors have a very wide effective dose area, so that,
depending on the object and diagnostic question at hand, the selection of
an optimal parameter adjustment is always possible.
Exposure times for size 1 and size 2
XIOS
Plus
X-ray sensors
Short exposure times are adequate for the highly sensitive size 1 and
size 2 XIOS
Plus
X-ray sensors.
The exposure parameters specified for X-ray sensors in the
documentation for the various Sirona intraoral X-ray systems therefore do
not apply to size 1 and size 2 XIOS
Plus
X-ray sensors.
Recommended exposure times for Sirona devices are described below.
Exposure times of 0.06 - 0.12 s correspond to dose values between
approx. 300 and 600 µGy at the sensor when measured without an object
NOTICE
Since the exposure time depends on the diagnostic problem as well as
the respective clinical situation, the selection of an optimal adjustment is
the responsibility of the treating physician.
NOTICE
Image degradations resulting from an insufficient dose
Image degradations resulting from an insufficient dose can be partially
compensated through image postprocessing.
CAUTION
Image degradations caused by overexposure of the sensor cannot be
compensated!
