The document describes the procedures for deflasking complete dentures from the stone mold and remounting them in the lab. For deflasking, a flask ejector is used to separate the dentures from the flask without damage. For lab remounting, the dentures are placed back on the articulator casts and wax-sealed to adjust the occlusion and correct any errors from processing, restoring the proper vertical dimension and balanced occlusion through selective grinding. Lab remounting allows correction of processing errors before finishing and delivery of the dentures.

2. DEFLASKING OF
COMPLETE DENTURES AND
LABORATORY
REMOUNTING

3. Learning outcomes
1. Describe deflasking procedure.
2. Explain lab remounting procedure.
3. List the purpose of doing lab
remounting.

4. DEFLASKING
 When deflasking complete
dentures, it is best to use flask
ejector, which allows removal from
the flask without damage to the
denture or flask.

5.  Hammering stone from flask with
plastic hammer or metal L wrench
eventually ruins flask and often
breaks denture base or teeth.

6. PROCEDURE
 Remove the lid from the flask
containing the denture.

7.  Place the flask bottom side up in
the flask ejector, and tighten the
thumbscrew until it contacts the
bottom plate.

8.  Place the pry bars through the
slots in the side of the flask
ejector, and engage the slots in
the flask between both halves of
the flask.

9.  With pry bars engaged, pry down
on them to separate bottom half
of flask.

10.  And then pry up. These
movements readily separates the
flask from the stone enclosed
denture.

12.  Tap back of knife blade with plastic mallet
to separate stone cap.
 Separating medium properly applied
facilitates separation of stone cap,
exposing cusp tips of denture teeth.

13.  With a saw, cut through the stone
that encloses the denture
opposite the central incisor teeth.

14.  Additional saw cuts are made at
distobuccal corners of flasked
denture.

15.  So that the stone enclosing the
denture has three cuts.

16.  Place a knife in the anterior saw
cut, and pry gently to separate
the stone from the buccal and
anterior flanges of the denture.

17.  Investing stone removed except
around base of cast.

18.  Protect denture teeth with hand
before tapping away remaining
stone.

19.  Clean out the index grooves on the base
of the cast.
 This cleaning makes it possible to
position the cast accurately on the
mounting stone for correction of
processing error.

20.  After recovery from the stone, the
dentures are ready for
remounting on the articulator.

21. LABORATORY
REMOUNT
PROCEDURES

22.  Remount Procedure: any method
used to relate restorations to an
articulator for analysis and/or to
assist in development of a plan
for occlusal reshaping.

23.  Acrylic resins shrink when they
change from a moldable to a solid
form. They have a high coefficient of
thermal expansion, and in cooling
after polymerization they shrink
causing dimensional changes.

24.  These faults can be corrected by
careful selective grinding
procedures.
 Laboratory remounting the
dentures on the articulator and
selective grinding procedures
should be carried out before
polishing the dentures.

25. Ignoring this important step will
lead to:
1.trauma to the underlying soft
tissues,
2.discomfort, and
3.destruction of the supporting
bone.

26. Laboratory Remount
Purpose:
1. To correct errors in occlusion
that have occurred during
processing.
2. To return dentures to the correct
vertical dimension of occlusion.
3. To restore centric and bilateral
balanced occlusion.

27. LABORATORY REMOUNTING

30. The processed dentures are
removed from the flasks.

32. Place each cast on its plaster
mounting and check that it goes
to place exactly.

33. After the index grooves are cleaned, the
dentures and casts are sealed to the
mounting stone with sticky wax.

34. The objective is to restore the vertical
dimension of occlusion to the level
achieved with the trial denture.

35. 0.5-1 mm incisal pin opening is
acceptable

36. Tap the two members of the articulator
together with articulating paper
between them.

38. These contacts are restored with
selective grinding by using BULL
(Buccal Upper/ Lingual Lower)
principle.

40. Do selective grinding till the
incisal pin touches the incisal
table.

41. Lab Remount
Upon completion, the articulator should slide
easily from working to balancing to protrusive
and back.
BalancingProtrusive Working

42. Questions