EQUIPMENT FOR CRANIAL AND DENTAL RADIOGRAPHY, PANTOMOGRAPHY, CEPHALOMETRY, DENTAL RADIOGRAPH

1. Rukmanee
Assistant Professor
Mewar University

2.  Record of an image produced by transmission of x-rays
through an cranium and dental that is called cranial and
dental radiography .
 First dental radiography discovered in 1896 by O walk
Hoff .
 Cranial and dental radiography are easier, faster and
generally more accurate procedure .
 These examination are use high technical standard .

3.  Cranial table is much more readily
appreciated from practical
observation than from written
description.
 Fixed column provided support to
object table and x- ray tube.
 Object table which essential is a
bucky tray.
 Anode to film distance 90 cm.

4.  Base design-
T or round -shaped
Floor – ceiling mounting
Floor – wall mounting
 Double semi circular arch –
x-ray tube
counter weight

5.  Upper and lower sections are made
up of transparent “Plexiglas ”.
 Upper surface- large circular
protractor scaled in four quadrants of
90⁰ angle.
 Anatomy of interest for positioning.
Under the table are a pair of lighted
mirrors to look for accurate body.
 Arches and object table are mounted
together on the column by a single
carriage.

6.  The couch is neither an integral part of the equipment nor
as a rule in a fixed relationship to it .
 It can be raised or lowered hydraulically and its usually
built in three hinged sections.
a) Tilting 1/3rd reclining angle- for back rest nearest to
skull table.
b) Middle 1/3rd is horizontal surface- forms a seat.
c) Remaining 1/3rd dropped vertically downwards-
supports the knees and calve.

7.  The couch can be converted into a chair and can be used
for the examination of the patients in sitting position.
 For patient immobilization- arm rest , head rest, shoulder
rest and sling for the chin.

8.  Whole device of object table & x-
ray tube can be moved up and
down supporting the column .
 Whole device can be rotated 360
degrees.
 The x-ray tube can be tilted
independently on its own axis + -
30 degree.
a) Angulation of x-ray tube
b) Tilting the object table
c) A combination of putting some
of the tilt on the table and
some on the x-ray tube.

9.  The upper and lower sections of
the table are made of transparent
Plexiglas.
 Upper surface are etched a pair of
cross lines intersecting at the
centre of the field.
 Under the table are a pair of
lighted mirrors. It permits the x-
ray beam to be centred accurately
on surface anatomical landmarks
which are near to the film and
ordinarily lost to sight because of
this .

10.  Immobilizing devices - band , head clamps may be used which
fix to the side of table.
 Beam limiting & centring devices – usually limitation of x-ray
beam is obtain by removable diaphragms which are slotted into
the tubehead . Visual indication of the direction of the primary
beam is provided either by a centre finding pointer or by varay
lamps.
 Spring loaded cassette boxes – spring loaded cassette boxes for
cerebral angiography. the Bucky mechanism is removed &
replaced with the box which will be employed for the
anteroposterior projection, the box for the lateral projection is
fitted to the edge of the table in the same position as the
cassette holder described earlier .

11.  There are three significant parts of the
dental equipment –
1.Tubehead
2.Tubestand
3.Timer

12.  Tube head is Oil filled & vacuum
sealed.
 Tube head are present high tension
transformer, filament transformer,
x-ray tube, oil -expansion
diaphragm.
 Tube head mounted in a
contrivance known as gimbals in
which it is free to rotate in two
planes.
 Localising cone is provided for the
tubehead giving an anode - skin
distance of 18- 23 cm (7 – 9 inch).

13.  Tube head is mounted on a tube stand.
 Tube stand is mounted in one of the following ways:
1.On the wall by means of a bracket.
2.On a mobile pedestal which moves on four large castors.
3.On the dentist's pedestal control.

14.  The timer is of the electronic type.
 Provides maximum exposure interval of 5 sacs.
 A red pilot lamp indicates when x-rays are 'on'
and the exposure push- button is designed to
prevent any operation as the result of
accidental pressure.

15.  The cylinder (or cone) is a fixed to the tube head and is used
to align the tube head with the patient and the X-ray film.
 It is open ended and composed of lead laminated material that
establish the minimum distance from the x-ray source to
patients skin.

16. Cephalostats
 Cephalostat is an apparatus which permits a precise
correlation position to be established between an x-ray
film, head of patient and the anode of x-ray tube .
 Cephalostat is a wall mounted & of a strong rigid
structure.
 Patient is laterally pinned by the ears by means of ear
plugs in a fixed relationship to a cassette-holder X-ray
tube which is shown in neither illustration is at another
fixed point.

17.  The Orbital indicator, nasal positioner & scales showing
certain distances all play a necessary part in the indication
recording and subsequent reproduction of a particular
radiographic situation.
 Filter prevent over penetration on radiograph of the nasal
bone and soft tissue.
 Generators can provide max current 7 – 12 mA and
voltage 50 – 55 kvp .

21.  Pantomography equipment provide panoramic
radiographs of jaw and face that is all teeth together
with mandibles and maxillae are seen on single film
15cm. X 30cm.
 These are use smaller radiation dose.
 These are use demonstration of temporomadibular
joint, fracture of facial bone, developed abnormalities,
dental cyst.
 Duration of exposure varies for different
equipments normally it takes 15 seconds for whole
examination.

22.  Effective tube focal area 0.6mm x
0.6mm. Total filtration is equivalent
to 3mm Al.
 Cassette is curved and these convex
surface is facing the tube.
 Beam is collimated by :
1) primary diaphragm .
2) secondary slit panel .

23.  Patient supporting/immobilizing
device –
1) bite block
2) chin support
3) forehead support
4) RT and LT temporal support
5) RT and LT Perspex face plates