This document discusses the boxing and pouring of final dental impressions. It describes two methods for boxing impressions - wax boxing and plaster of Paris/pumice boxing. The key steps of each method are outlined. It also discusses pouring dental stone casts, including proper mixing and vibration techniques. Indexing casts is described as important for remounting procedures, with groove and notch methods presented. Ensuring indexing does not weaken or become detached from casts is emphasized.

2. FINAL IMPRESSION BOXING AND
POURING
Guided By: Dr. Manesh Lahori
Dean & Head
Dept. of Prosthodontics
K.D.D.C
Presented By:
Dr C.Pradeep
P.G. Student

4. CONTENTS
 INTRODUCTION
 METHODS OF BOXING IMPRESSION
 POURING CASTS
 INDEXING THE CASTS
 METHODS OF INDEXING
 REFERENCES

5. Introduction
 Final impression : The impression that
represent the completion of the registration of
the surface or object.
 Boxing can be defined as the enclosure (box)
of an impression to produce the desired size and
form of the base of the cast and to preserve
desired details
 Beading is done to preserve width and height of
sulcus in a cast and boxing is done to obtain a
uniform smooth well shaped base of the cast.

6. Advantages of Beading and boxing final
impressions before pouring
 Preserves the extension, as well as the
thickness, of the border;
 Controls the form and thickness of the base
of the cast
 Boxing also facilitates placing remounting
plates in the cast; and conserves artificial
stone.
 It ensures the capture of the mucobuccal
and mucolingual borders of impression.

7. METHODS OF BOXING
 WAX BOXING METHOD
 PLASTER OF PARIS AND PUMICE BOXING
METHOD

8. WAX BOXING METHOD
 Wax boxing is effective for zinc-oxide paste
impressions and is usable also for rubber base or
silicone impressions, but only after thoroughly
drying them before adapting the beading wax
 After the beading wax is adapted and sealed, the
impression is boxed with a wax strip, and the
cast is poured

9.  PROCEDURE
 1. Adapt orthodontic tray wax or beading wax around the
periphery of the impression . This wax should be
approximately 4 mm wide and 3 to 4 mm below the border
of the impression.
 2. Adapt another short length of beading wax to the heel
region of the mandibular impression and across the
posterior edge of the waxed-in tongue area to make the
border wider in these areas .

10. 3. Seal the beading wax to the impression with a
wax spatula . Handle the hot spatula carefully to
avoid damaging the impression or allowing the wax
to flow onto the border of the impression.
4. Check the width of the beading by looking down
on the impression from directly above to determine
whether a border of acceptable width is visible
around the entire impression .

11. 5.Place the impression on the bench with impression surface up. and
use soft wax or modeling clay to align the impression so that the
ridge portion is approximately parallel to the bench top
Adjust the height until a boxing wax strip extends approximately
13 mm above the highest point on the impression
6.Fill in the tongue space of a mandibular impression by adapting and
sealing a sheet of baseplate wax cut to the proper form. Use a wax
spatula to seal the wax to the impression

12.  Seal it to the impression on both sides .
 Make the waxed-in tongue area smooth and seal it
approximately 3 to 4 mm below the border of the
impression.
 Lower placement will compromise access to parts of the
cast, such as when making baseplates.

13. 7. Seal the ends of the boxing
strip to the underlying
layer of wax
8. Seal the beading wax to the
boxing strip on both
the impression side and the
underside to make it watertight
Handle the hot spatula carefully
to avoid perforating the boxing
wax or dripping wax into
the impression.
9. Check the boxed impression
for adequate width of the border,
sealing, and height before
pouring it in stone . Fill the
impression with cool water to
check for leaks.
Pour the impression in vacuum
spatulated* artificial stone

16. Plaster of Paris and pumice boxing
method
 The plaster of Paris and pumice boxing method is
excellent for boxing impressions of rubber base
or silicone materials because maintaining contact
between the boxing material and the impression
material presents no problem.

17. PROCDEDURE
1. Make a 1: 1 mixture by volume
of plaster of Paris and flour of
pumice, and stir thoroughly while
dry to assure uniformity . The
pumice weakens the set plaster
and facilitates separation of the
cast after pouring. Approximately
200 gm of plaster usually is
adequate for the majority of
impressions.
2. Add enough water to make a stiff
mix and Spatulate thoroughly .
3. Place a patty of the mix on a
glass slab.

18. 4. Keeping the ridge portion of
the impression parallel to the
bench top, settle the impression
into the patty. Use a spatula to
draw the plaster mix around the
impression until it is 3 to 4 mm
below the border.
5. Smooth the plaster mix
around the impression with a
wet spatula to make the border
of the cast smooth .
6. As the plaster and pumice
mix begins to set, trim
it to remove excess material. Do
not trim closer than 5
to 6 mm .

19. 7. After the plaster has set, remove it from the glass slab,
and trim it on a cast trimmer until the border is 4 mm wide .
Set the cast trimmer table to produce sides on the cast that
are perpendicular to the base.
8. Trim the plaster with a sharp knife until it is 3 to 4 min
below the border of the impression. This is especially
necessary in the heel region of mandibular impressions and
across the posterior border of maxillary impressions . In
these regions the plaster may be 2 mm below the border.
9. Remove the plaster that adheres to the border of the
impression by brushing gently with a soft-bristle
toothbrush

20. 10. Adapt the boxing wax to the invested impression
so that the wax extends at least 13 mm above the highest
point on the impression .
11. Seal the boxing strip to the plaster with a hot spatula and
wax .
12. Paint the plaster surfaces with a separating medium
13. Fill the boxed impression with cool water to
check for leaks. The water also wets the plaster,
thereby minimizing voids in the stone cast that can occur
when pouring stone onto dry plaster.

21. 14. Proportion the stone by weight, according to
the manufacturer’s recommendation, mix it in a
vacuum spatulator under reduced atmospheric
pressure, and pour the cast . Generally 200 gm of
artificial stone is enough to pour most impressions,
but large ones may require more.
15. After setting, cut away the plaster and pumice
hexing, and remove the impression and cast .
16. Place the impression and cast in a plaster bowl
containing warm water to soften the impression
material, permitting separation without breaking
the cast. Do not overheat, or the compound may
stick to the cast.

22. 17. Using a sharp knife, reduce
the height of the border on
the.cast where necessary.
18. Adjust the width of the
border of the cast on a cast
trimmer until it is approximately
4 mm. Soak the cast in clear
slurry water for 3 to 4 minutes
before trimming it to prevent
slurry splatter from the cast
trimmer from sticking to the cast
Trim the sides of the cast
perpendicular to the base .
19. The trimmed cast is ready
for fabrication of the baseplate.

24. PROBLEM AREAS
 The boxing wax should be high enough above the
impression (13 mm) so that the cast will be thick enough.
 The impression should be parallel to the bench top when
settling into the plaster and pumice mixture to ensure that
the base of the cast is of uniform thickness.
 The plaster should have a coat of separating medium
before pouring the impression to avoid breaking the cast
during separation.
 The boxing wax strip should not be overly soft prior to its
adaptation to the trimmed plaster and pumice-encased
impression.

26.  It is easy to distort an oversoft wax strip and
thereby make the border of the east too thin
 The impression and encasing plaster and
pumice should soak in cool water for 3 to 4
minutes prior to pouring.
 This soaking will reduce the* frequency of
voids associated with pouring stone against a
dry plaster and pumice surface. A good
quality artificial stone, proportioned by
weight according to specification and
preferably mixed in a vacuum spatulator
under reduced atmospheric pressure, will
prevent soft casts and voids

27. POURING CASTS
 Careful attention when trimming the cast on the cast
trimmer will result in fewer overtrimmed borders
 Wetting the cast in clear slurry water prior to trimming will
reduce the incidence of slurry splatter sticking to the cast,
which is difficult to remove.
 A separating medium always should be painted on the
plaster and pumice boxing prior to pouring the stone cast.
Boxing the impression is the first step in making an
acceptable cast. The second, equally important, step is
correct pouring of the cast.

28.  It is necessary to proportion it by
 Weight and mix it with the specified amount
of water.
 Mixing the stone in a vacuum spatulator
under reduced
 Atmospheric pressure makes the stone mix
and cast superior.
 The resultant stone mix is smooth and free of
air bubbles, and the cast is strong and
dense.

29. PROCEDURE
1. Proportion the stone by weight, and add it to the
recommended amount of water . Usually,
200 gm of stone is ample for pouring the majority of
boxed impressions.
2. Spatulate the stone under reduced atmospheric
pressure for 20 to 25 seconds. Usually spatulation
for 20 to 25 seconds is sufficient, but it is necessary
to follow the manufacturer’s recommendations
for individual stones.
3. Vibrate the mix into the boxed impression.
Add stone in only one area of the impression, and tilt
the impression on the vibrator to allow stone to flow
over the entire impression, thereby minimizing voids

30. 4. Continue adding stone until the boxed
impression is full .
5. Allow the poured impression to set before
separating the cast. Many dental stones set hard
enough to separate between 45 minutes and 1
hour after mixing.
6. Trim the border of the cast, as described
previously

33. PROBLEM AREAS
 The principal problems when pouring casts relate to
improper powder-water ratios, which can result in a
markedly inferior, soft cast of inadequate strength
 Incorporating voids or air bubbles during pouring and
incorrect trimming of the poured cast also can be
problems.
 Omission of the separating medium can result in
broken casts when using the plaster and pumice
boxing method. Adherence to the powder-water ratios
recommended by the manufacturer (weighing the
artificial stone and mixing it with the recommended of
water).
 Mixing in a vacuum spatulator under reduced
atmospheric pressure, and careful pouring technique
contribute to producing strong, dense casts with
superior surfaces.

34. INDEXING THE CAST
 Indexing casts prior to mounting them in an
articulator permits removal of the casts and accurate
replacement in the articulator.
 Indexing is particularly helpful during remounting
procedures, such as when correcting processing
errors after curing a denture. Indexed casts also are
useful during the split-cast method for verifying jaw
relation records.
 Grooves, notches, or special metal* or plastic
remounting plates are placed in the cast for indexing
.

35. Requirements for indexing
 It is axiomatic that the indexing should not weaken
the cast so that it breaks during routine laboratory
procedures.
 Neither grooves nor notches used for indexing
should be undercut to form a mechanical lock with the
mounting stone. The indexing should remain functional
in the event that the size of the cast must be reduced
to fit the flask at the time of processing .
 The index should provide a positive three-dimensional fit
between the cast and mounting stone, permitting easy
removal and accurate replacement without damage to
the cast or mounting.

36. Problem
Cast broken by
improperly cut index
Cast unable to be
separated from
mounting stone
Lingual flange area of
cast perforated by
indexing groove
Probable cause
Indexing grooves too
deep
Indexing notches or
grooves undercut or
separating medium
not applied prior to
mounting
Indexing groove too
deep
Solution
Place indexing
grooves with trued
lathe mounted wheel;
make them approx
3/16 inch(0.47 cm)
deep
Do not incorporate
undercuts in grooves
or notches paint
separating medium on
cast base prior to
mounting
Do not make groove
too deep in
mandibular cast with
deep lingual
extensions, place
grooves in opposite
ridges, not in thinner
portion of cast

37. Groove indexing method
 Indexing a cast by grooving the base of the
cast with a lathe-mounted wheel offers
several advantages
 Contouring the lathe wheel will produce a
smooth V cut without undercuts.
 Groove indexing allows reduction of the cast
border if necessary while retaining a positive
index. It is possible to modify the position of
the index groove as needed to avoid thin
areas in the cast.

38. PROCEDURE
1. Shape the lathe-mounted wheel with a trueing
stone to make a V-shape edge .
2. Groove the center of the base of the cast from
front to back with the wheel .
3. Groove the rest of the cast perpendicular to the
first groove, intersecting approximately in the
center of the cast .
4. Where lingual flanges result in thin areas in
mandibular casts, place the grooves opposite the
ridges in thicker portions of the cast .

39. Notch indexing method
 Notches cut in the base of the cast at three
points provide a positive index.
 The notch method is especially suitable for split -cast jaw
relation record
 This method has a potential disadvantage in the event
that it is necessary to reduce the cast significantly to fit in
a flask / In this instance,/ the removal of peripheral
notches can result in the loss of the index.

40. PROCEDURE
Notch the base of the cast in the anterior
midline and in the right and left
distobuccal regions
Use a lathe mounted wheel or sharp knife
to make smooth undercut notches

41. PROBLEM AREAS
 The principal problems in the groove or notch
method of indexing casts are making the grooves
or notches too deep, thereby weakening the cast ,
and undercutting).
 The notches or grooves, resulting in mechanical
locks between the cast and mounting stone
As discussed earlier, it is necessary to reduce the
size of a cast occasionally to fit a flask .
 Cutting away notch indexing in these instances
will eliminate the index; a result, the groove
method is preferable

42. REFERENCES
 Dental Laboratory procedures complete
dentures( Robert M Morrow, Rudd,
Rhoads) First south asia edition

43. A GOOD IMPRESSION….
Requires time and effort
Ensures an accurate and detailed cast
THANK
YOU