Villa Rotograph EVO, Service Manual

Page: 147 / 223

SERVICE MANUAL
Troubleshooting
Rotograph EVO (Rev. 1) 8-56
8.4. Search and correction of possible defects in dental
radiographies
8.4.1. Defects due to incorrect position of the patient
Problem Description Solution
Incisors too large and
blurred. The patient is not positioned
correctly. He is too far back
from the optimal focal plane.
Position the patient correctly, and
verify that he is holding the bite with
his incisors on the fit notch and that
the bite holder rod is vertical.
Incisors too small and
blurred. The patient is not positioned
correctly. He is too far
forward of the optimal focal
plane.
Position the patient correctly, and
verify that he is holding the bite with
his incisors on the fit notch and that
the bite holder rod is vertical.
Radiography with
blank central area. The patient's spine inhibits
the passage of the X-rays
because it is too
compressed.
Check the alignment of the
Frankfurt plane. Try to stretch out
the cervical tract of the spine
correcting the height of the cursor
and moving the patient's feet
forward (see 6.4.3.3/4/6/7 of the
User Manual).
Dental arch not
symmetrical. The median sagittal line
does not correspond to the
laser centering beam. Realign the patient (see 6.4.3.6 of
the User Manual).
Upper apical area too
dark. The patient does not keep
his lips closed and his
tongue is not against the
palate.
See paragraph 6.4.3.8 of the User
Manual.
Upper central apical
area out of focus. The patient's head is turned
backwards (Frankfurt plane
not aligned).
Position the patient correcting the
Frankfurt plane.
The image is slanted
with respect to the
longitudinal axis of the
film and some of the
anatomical structures
are not symmetrical.
The patient's head is slanted
(not vertical). Position the patient correcting the
sagittal plane.
The teeth are bigger on
one side than the
other.
The patient's head is turned
with respect to the axis of
the bite.
Position the patient correcting the
sagittal plane and checking that the
test is not turned.
(In CEPH examination)
white area on the
lower part of the film.
Panoramic chin-rest
mounted. Repeat the examination removing
the PAN chin-rest.