Owandy Radiology i-max touch, Service Manual

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SERVICE MANUAL
Troubleshooting
I-Max Touch 8-59

Part of the image is enlarged while the other one is reduced
The schema described on Figure 8-6 the image obtained; it is
possible to observe that one part of the radiography is blurred and
enlarged, while the other one is reduced and seems to be on focus;
the two condiles are at the same height on the film.
Figure 8-6
Possible cause:
This effect can be due to two different causes.
In the first one, the median-sagittal plane is not
aligned with the relevant centring light beam, which
falls at the centre of the chin support.
In the second case instead, the centre of the median-
sagittal plane matched the centre of the chin support,
but the patient’s head is rotated.
In both cases, one side is closer to the image plane than the other,
thus resulting in a different magnification of the two sides; the part
more distant from the sensor will be more magnified while the part
closer to the image plane will result smaller. This error in positioning
the patient will result in a radiography as shown in picture above:
the right-most area of the image shows a bigger magnification that
can be noticed either on the teeth and on the ascending rami of the
TMJ.
Remedy:
Check the positioning of the median-sagittal plane by using the
relevant centring light beam.
A more accurate check is performed using the special tool and
making an image; the dimensions measured on the obtained image
must match those reported in the paragraph 7.1.1.