how to make a cast with removable dies for fixed restorations

2. What is fixed prosthesis ?
is the area of prosthodontics focused
on permanently attached
(fixed) dental prostheses. Such dental
restorations, also referred to as
indirect restorations,
include crowns, bridges (fixed dentur
es), inlays, onlays, and veneers.

3. HOW WE PREPARE THE WORKING CAST WITH
REMOVABLE DIES?

4. Thedentistfinishes preparing
thetoothand takes
impressionwith silicone
material.
Note: the dentist takes the
impression with silicone because the
silicone is an
accurate and stabile material that fixed
need it.
Then the dentist sends
the impression to the
laboratory to start
working on it.
Note: it is very important to sterilized the
impression to avoid any infection.

5. vacuum mixer is used to
minimize the amount of air
incorporated into the mix.
* The vibrator used to get all
bubbles out
put a specified amount of die stone
and distilled water in
the *vacuum mixer.
Once the die stone mixed we ready
to pour the impression .
Put the impression on the edge of
The*vibrator and apply the die
stone from one side and let it flow
to the other side .

6. A device with a large abrasive
wheel for reducing and shaping
the stone models.
A wet trimmer uses a water
wash away the trimmings.
A dry trimmer uses a vacuum
to collect the dust particles
from trimming.
Separate the stone cast when set
and trim it to horse shoe.
The base must be absolutely big
and irregular in shape, the height
of the base must be10-15 mm
from free gingival margin.

7. This is the cast properly trim and the
horseshoe outline with the 10 mm from
the gingival margin

8. Draw a line from
the prepared
tooth to the
edge of the cast
Draw a point on
the base from the
opposite side of
the cast
(this point make easy to identify
the areas we are going to be
placing our dowel pin )

9. PINDEX
• Bypindexmachinemakeaholeonthecastto
put the pins.
• Checkthat all pinscanenteron theholebefore
fixingit.
• Usealittle bit of superglueto stick thepins
onthe cast.

10. PINDEX
-Isolatethecast.
-Makethebaseofthecast
by mixstonethenputthe
cast overthe stone base.
-Trytoseparatethecast
fromthe basebyuse
hammerafter settingthe
stone base.
(do not apply a high force , the cast
maybe break)

11. SAWING
With a saw frame and a thin saw
blade , cut between the prepared
tooth and the adjacent tooth .
• (it is important to pay attention not to
damage any adjacent teeth)
• The saw cut should start in the
interdental papilla area and
extend downward on a very slight
taper.
• The occlusal saw cut should
extend three quarters of the way
through the stone base .
• Use your finger to press the pin
from the bottom to come out of
the cast.

12. -Mark the finish line with red pencil and
be careful notto destroy the finish line.
-Prepare the die with tungeston and
rose head burs and sand paper.

13. COMPLETING THE DIE
After cast and die preparation there is three steps before starting wax up :
Die hardener :
material applied
on the surface of
die to increase the
surface hardness .
Die spacer : apply on layer
of die spacer to
compensates for cement
thickness.
You can added more than
one layer as requested by
the dentist
( this should finish 1mm
above the margin to ensure
a tight marginal fit)
Isolator: apply
isolator on the die
, adjacent and
opposing teeth ,
by using a brush
then, remove the
excess using a
paper tissue.

14. Now you can start
waxing Show us
what you can do

*Organized by :
- Dt. Sarah Omari
*Done by :
- khawla mousa
- Ameera masoud