When a good impression of the prepared tooth has been made in the mouth, it's important that it may be handled properly to obtain accurate and detailed casts. As the direct fabrication of patterns for extra-coronal restorations in the mouth is inconvenient, time-consuming, and virtually impossible, all the wax patterns are made in the laboratory using the indirect technique. This requires an accurate working cast with removable dies with a detailed reproduction of prepared tooth, and soft tissues to produce restorations that fit as accurately as possible.

1. Presented by-
Dr. Kumari Kalpana
PG - 2 PAGE 1

2. C
O
N
T
E
N
T
PAGE 2
Introduction
Definitions
Ideal Requirements
Various Die materials
Die Hardener
Die Spacer
Die Separator
Die preparation
Die systems
Conclusion
References

3. PAGE 3

4. DIE: The positive reproduction of the form of a prepared tooth in any
suitable substance. (GPT-9)
 A reproduction of a prepared tooth made from a gypsum product, epoxy
resin, a metal or a refractory material (Philips).
4
Definitions

5. Die spacer: An agent applied to a die to provide
space for the luting agent in the finished casting.
(GPT-9)
Electroplating:
The process of covering the surface of an object with a thin coating of metal by means
of electrolysis (GPT-9)
5

6. Die preparation:
According to Shillingburg,
Die preparation involves trimming the die apical to the finish
line of the preparation to facilitate good axial contours in the
finished restoration.

7. PAGE 7Rosensteil SF, Land FM, Fujimoto J. Contemporary fixed prosthodontics.3rded. St.Louis:Mosby;2001

8. It must reproduce the prepared
tooth.
All surfaces must be accurately
duplicated.
No bubbles or voids.
Rosensteil SF, Land FM, Fujimoto J. Contemporary fixed prosthodontics.3rded. St.Louis:Mosby;2001 PAGE 8

9. 4. The remaining unprepared tooth structure
immediately cervical to the finish line should be
easily discernible on the die.
5. Adequate access to the margin is imperative
Rosensteil SF, Land FM, Fujimoto J. Contemporary fixed prosthodontics.3rded. St.Louis:Mosby;2001
PAGE 9

10. Rosensteil SF, Land FM, Fujimoto J. Contemporary fixed prosthodontics.3rded.
St.Louis:Mosby;2001
PAGE 10

11. 1. It must reproduce both prepared and
unprepared tooth surfaces.
2. The unprepared teeth immediately
adjacent to the preparation must be free of
voids.
Rosensteil SF, Land FM, Fujimoto J. Contemporary fixed prosthodontics.3rded. St.Louis:Mosby;2001 PAGE 11

12. 3. All surfaces of any
teeth involved in anterior
guidance and the occlusal
surfaces of unprepared
teeth must allow for
precise articulation of the
opposing casts.
Rosensteil SF, Land FM, Fujimoto J.
Contemporary fixed prosthodontics.3rded.
St.Louis:Mosby;2001
PAGE 12

13. 4. All relevant soft tissues should be
reproduced in the working casts
including edentulous spaces and residual
ridge contours that will be involved in
fixed prosthesis.
5. Must be bubble free, especially along
the finish lines of the prepared teeth
Rosensteil SF, Land FM, Fujimoto J. Contemporary fixed prosthodontics.3rded. St.Louis:Mosby;2001 PAGE 13

14. 6. The casts must be trimmed to
ensure access for carving wax pattern
margins.
7. Each cast must have a base that
allows firm attachment to the
articulating instrument
Rosensteil SF, Land FM, Fujimoto J. Contemporary fixed prosthodontics.3rded. St.Louis:Mosby;2001 PAGE 14

15. DIE MATERIALS2,3
Phillips, RW. Skinner's Science of Dental Materials. 11th ed. The WB Saunders Co, Philadelphia; 1982.
Rosensteil SF, Land FM, Fujimoto J. Contemporary fixed prosthodontics.3rded. St.Louis:Mosby;2001
PAGE 15

16. http://deltauniv.edu.eg/new/dentistry/wp-content/uploads/Lecture-1-2-2016-Dr-Ghazy-Working-cast-and-die.pdf PAGE 16

17. Stone die or gypsum die
Amalgam die
Acrylic or epoxy resin dies
Electroplated dies – silver plated, copper plated
Flexible die
Ceramic die
Refractory materials – gypsum bonded die material
DIE MATERIALS
PAGE 17

18. The selection of any of the materials is
determined by the following:
The impression material in use.
The purpose for which the die is to be used.
18

19. GYPSUM DIES2,3
19
Phillips, RW. Skinner's Science of Dental Materials. 11th ed. The WB Saunders Co, Philadelphia; 1982.
Rosensteil SF, Land FM, Fujimoto J. Contemporary fixed prosthodontics.3rded. St.Louis:Mosby;2001

20. Gypsum
products are
available in
five forms
(ADA Type I-
V)
Type I- Impression plaster.
Type II- Model plaster.
Type III- Dental stone.
Type IV- Dental stone with high strength.
Type V- Dental stone with high strength and
high expansion.
IV and V are used for making dies.
PAGE 20

21. Setting reaction results from the hydration of calcium
sulfate hemihydrate:
CaSO4 . ½H2O +1½H2O CaSO4 • 2H2O
+ heat (3900 cal/gm)
PAGE 21

22. Water/powder ratio: To attain maximum strength, surface hardness and a well
controlled setting expansion, it is necessary to gauge the amount of water and
powder as recommended by the manufacturer.
Type IV – 0.22-0.24;
Type V – 0.18 – 0.22
PAGE 22

23. Gypsum can
be mixed by:-
PAGE 23
Hand Mixing
Mechanical mixing

24. TYPE 4
 Abrasion resistant & minimum
setting expansion
 Because the surface dries more
rapidly, the surface hardness
increases more rapidly than does
the compressive strength
 the core of the die is tough and
less subject to accidental breakage
TYPE 5
 Exhibits even higher
compressive strength
 Setting expansion increased.
PAGE 24

25.  Two crucial characteristics of cast and die materials, dimensional accuracy
and resistance to abrasion while wax pattern is being formed, are
adequately achieved with gypsum.
 Surface detail reproduction with type IV and type V gypsum products is
acceptable for fixed prosthodontics.

26. Advantage of gypsum as die material3
Compatibility with all impression materials
Easy to use
Dimensional accuracy
Inexpensive
26
Rosensteil SF, Land FM, Fujimoto J. Contemporary fixed prosthodontics.3rded. St.Louis:Mosby;2001

27. Disadvantage of gypsum dies
 Susceptibility to abrasion
 Brittle prone to fracture
27Rosensteil SF, Land FM, Fujimoto J. Contemporary fixed prosthodontics.3rded. St.Louis:Mosby;2001

28. Gypsum dies can be modified:2
 To make them more abrasion- resistant
 To change the dimensions of the dies
 To increase the refractoriness of the dies
 To produce a combination of these effects
28
Phillips, RW. Skinner's Science of Dental Materials. 11th ed. The WB Saunders Co, Philadelphia; 1982.

29. 1) Methods to increase abrasive resistance2,3
 Silver plating
 Adding die hardener to gypsum (eg. Colloidal silica)
 Treat surface with resin (epoxy, acrylic, styrene or cyanoacrylate)
 Use gum arabic or calcium hydroxide mixture
 Application of additives used in industrial applications
29
Rosensteil SF, Land FM, Fujimoto J. Contemporary fixed prosthodontics.3rded. St.Louis:Mosby;2001
Phillips, RW. Skinner's Science of Dental Materials. 8th ed. The WB Saunders Co, Philadelphia; 1982.

30. 2) Methods of altering die dimensions2
Addition of accelerator (potassium sulphate) &
retarder (borax)
Reduce setting expansion of type IV die stone < 0.1%
Reduce diameter of die
30
Phillips, RW. Skinner's Science of Dental Materials. 11th ed. The WB Saunders Co, Philadelphia; 1982.

31. DIE STONE –INVESTMENT
COMBINATION DIES2
Phillips, RW. Skinner's Science of Dental Materials. 11th ed. The WB Saunders Co,
Philadelphia; 1982. 31

32. Divestment (Whipmix corp) +
Die is made & wax pattern fabricated on it
Die & pattern  invested in mixture of Divestment & water 
eliminates possibility of distortion of the pattern on removal from
the die
When it is heated to 677oC, setting expansion is 0.9% & thermal
expansion(0.6%)
32
Phillips, RW. Skinner's Science of Dental Materials. 11th ed. The WB Saunders Co, Philadelphia; 1982.

33. Advantage
Highly accurate technique for use with conventional gold alloys
Disadvantage
Divestment gypsum bonded material not recommended for
high fusing alloys
33

34. ELECTROPLATED/
ELECTROFORMED DIES1,2,3
34
1. The Glossary of Prosthodontic Terms. J Prosthet Dent 2005 Jul;94(1):10-92
2. Phillips, RW. Skinner's Science of Dental Materials. 11th ed. The WB Saunders Co, Philadelphia; 1982
3. Rosensteil SF, Land FM, Fujimoto J. Contemporary fixed prosthodontics.3rded. St.Louis:Mosby;2001.

35. ELECTROPLATED/ELECTROFORMED DIES1,2,3
Electroplating : the process of covering
the surface of an object with a thin
coating of metal by means of
electrolysis (GPT-9)
PAGE 35

36. Advantages3
Hard and abrasion resistant
Dimensionally accurate
Reproduce finer details
Prevent cuspal wear due to repeated contact with opposing
cast
36Rosensteil SF, Land FM, Fujimoto J. Contemporary fixed prosthodontics.3rded. St.Louis:Mosby;2001

37. Disadvantages3
Difficult to trim
Not compatible with all impression materials
In Silver electroplating, hydrogen cyanide release can occur
Wax pattern cannot be as easily adapted as on stone.
Plating can some times tear from the cast during separation.
37
Rosensteil SF, Land FM, Fujimoto J. Contemporary fixed prosthodontics.3rded. St.Louis:Mosby;2001

38. SILVER PLATED DIES4,5
38
Myers GE. Electroformed die technique for Rubber base impressions. J Prosthet Dent 1958;8:531-535.
Morrow RM, Rudd KD, Rhoads JE. Dental Laboratory Procedures. USA:Mosby;1986

39. COMPONENTS REQUIRED
Anode Cathode Electrolytic
solution
Source of current
PAGE 39

41. IMPRESSION MATERIALS
COMPATIBLE
Polysulfide
Silicones - distortion
NOT COMPATIBLE
 Polyether
 Hydrocolloids (reversible and
irreversible)
 Impression compound
41

42. Procedure
Preparing impression for plating
Plating the impression
Pouring cast into plated impression
PAGE 42

43. A)PREPARING IMPRESSION FOR PLATING:
1. The silver powder conductive coating is applied with a small inlay brush and
dusted into-
 cavity and teeth areas of the impression,
 interproximal papillae areas and
 to the gingival and mucosal areas around the teeth
to be plated.
43

44. 2. Excess powder removed by blast of air.
(care: no excess in tip of cusps.)
3. Metal tray used should be cover with wax.
44

45. 45
4. Plating current is conducted to the silvered impression through wires that are
inserted into suitable points of impression.
5. 20 gauge Cu wires with plastic insulation

46. 46
B) PLATING THE IMPRESSION
Electrolyte placed into deeper parts of impression with a pipette

47. Distance between Anode and cathode  minimum 4 inch
Current calculated on basis of 10 Ma per tooth
47

48. 48
Any area left unplated
repaint with Ag powder

49. 49
C) POURINGCAST INTOPLATEDIMPRESSION
the stone is poured into the impression in two stages :
i) First the stone is poured into the impressions
of the teeth in which cavities are prepared and
a dowel pin is inserted into each prepared tooth .

50. 50
ii) The knurled end of the dowel is completely
immersed in the stone, and the pins are
arranged to be parallel to each other and in the
line of the long axis of the tooth.
iii) After the stone has set, any irregular areas
are trimmed and then the pins and the stone
surface are coated with a separating solution or
a thin smear of petroleum jelly. The impression
is boxed with wax and stone is poured into it.

51. 51
 Silver plated die
 Remaining silver flash between
teeth severed with sharp scalpel.

52. Precautions
Cyanide solution should always be kept in cupboards with no acids nearby.
Place the bath in a well-ventilated area and avoid use of all the acids near the bath.
Addition of any acid  hydrogen cyanide gas  toxic. Plating solution be kept alkaline.
Silver plating solution poisonous avoid contamination of hands, working area etc.
PAGE 52

53.  Compared the accuracy of cast restoration fabricated on silver plated
dies and die stone dies. They concluded that marginal accuracy of
crowns fabricated on silver plated dies is statistically as accurate as
that of crowns fabricated on stone dies.8
53
Crispin et al. Silver-plated dies. Part II: Marginal accuracy of cast restorations. J Prosthet Dent 1984;51:768.

54. COPPER PLATED DIES7,8
54
7. Raymond L Cummins. A laboratory procedure for copper plating rubber base impressions. J. Prosthet. Dent. March 1975.
8. Cassimaty EM et al. Effect of three variables on the accuracy and variability of electroplated copper dies. Int J
Prosthodont 1996; ;9(6):547-54.

55. Components:
Apparatus : electrolyte bath with anode and cathode holders
Anode: pure copper
Cathode: Impression metallized
Metallizing agent:
Colloidal dispersion of graphite impression compound
Copper powder  silicones
55

56.  Electrolyte: acid solution of copper sulphate
 Copper sulphate crystals -200 gm source of copper
Conc. Sulphuric acid- 30ml increases conductivity of
solution
Phenol sulfonic acid - 2 ml  improves throwing power of
the solution
Distilled water - 1000 ml
56

57. Procedure
Same as for silver plating
Current passed is more as compared to Ag plating (5-
50mA for 10-15 hrs)
57
-

58. Impression materials compatible
Silicones
Impression compound
Not compatible
Poly ether
Hydrocolloids (reversible and irreversible)
Polysulfide
58

59. IF A RUBBER BASED IMPRESSION MATERIAL IS
ELECTROPLATED WITH COPPER7 :
i) The electrolyte used must be neutral or slightly acidic in reaction.
ii) The electrolyte must be heated to approx. 1150C and kept in constant
motion .
iii) A silicone separating media must be applied before coating the
impression with the metallizer.
59Raymond L Cummins. A laboratory procedure for copper plating rubber base impressions. J. Prosthet. Dent. March 1975.

60. Distancebetweencathodeandanode
 Greater the distance more even quantity of Cu deposited, more readily
are deeper areas plated
 4-6 inch suitable
 If distance less more Cu deposited on superficial areas of impression,
leaving deeper areas inadequately plated.
60

61. Compared the accuracy of electroplated copper and stone dies and concluded
that copper plated dies were more accurate than the stone dies. Also the
stone dies were found to be oversized compared to the master die.
61
Cassimaty EM et al. Effect of three variables on the accuracy and variability of electroplated copper dies. Int J Prosthodont
1996; ;9(6):547-54.

62. PROBLEMS OF ELECTROPLATING
Faulty conduction of current Short circuit exposure of
conducting wire to the solution
Exhausted solution Plating slow
Over concentrated solution Soften surface of impression
materials
Metal anode too small Slow and irregular plating
62

63. Current too high
 Gas bubbles at the surface of impression
 Granular and friable deposits unsatisfactory die
 Heavier deposits on areas of impression nearer to anode
 Some times failure to adequately cover the deeper areas of an impression
Current too low
 Satisfactory results take longer time to get necessary thickness
63

64. AMALGAM DIE2,3,5
 Alloy proportioned  triturated condensed in the impression
 Can be used with rigid impression materials only
Advantage:
 Reproduction of fine details and sharp margins is good
 Hard and high abrasion resistance
64

65.  Used only in copper band impressions
with modelling compound, and
 Contraindicated with rubber base
impressions due to elastic properties of
the material so it will not withstand
the forces of amalgam condensation.
65

66. Disadvantage:
 Only in rigid impression materials
 Takes long time to reach maximum hardness
 Improper manipulation can lead to significant dimensional changes in the
resulting die.
66

67. RESIN DIES2,3,5
67

68. They are self curing polymeric materials with fillers.
eg:
Acrylic resin die
Epoxy resin dies
Polyester resin dies
Compatible with polysulfide or polyether impression materials.5
68

69. ADVANTAGES5 :
 Better abrasion resistance
 High compressive strength than dental stone.
DISADVANTAGES5 :
• More viscous than dental stone so more entrapment of air in the preparations.
• Shrink upto 0.02% on polymerization
PAGE 69

70. EPOXY RESIN1
 A resin characterized by the reactive epoxy or ethyloxyline groups that
possess unique characteristics in terms of adhesion to metals, woods,
and glasses (GPT-9)
 Epoxy resin die: a reproduction formed in epoxy resin (GPT-9)
70

71. EPOXY RESIN
 Supplied as resin paste and liquid
activator (amine)
Trade names:
 Epoxydent, Oxydental products
 Epoxy die material, Dentsply
 Pri-Die, Jelenko
 Diemmet 71

72. 72
Working time 15 mins
Setting time 1-12 hrs (depending on product)
Shrinkage 0.03%-0.3%
Hardness (after 24hrs) 83-94 (Rockwell N)

73. Relatively long setting times,
 Incompatibility with certain impression materials and
Polymerization shrinkage.
All dies aged beyond 24 hrs were found to be unsuitable for use in
precision fixed prosthodontic procedures.
739. Vermilyea SG, Huget EF. Evaluation of resin die materials. J Prosthet Dent 1979;42;304.
Compared resin die materials with die stone and concluded that advantages
offered by the strength and hardness of resin die materials are overshadowed
by9

74. 74

75. They are similar to heavy bodied silicone or Polyether
impression materials and are used to make interim
restorations or indirect composite resin inlays or onlays
chairside.
75

76.  Impression made
 Silicone release agent
sprayed
76

77.  Flexible die Material injected in the
Impression
 Putty applied to force the impression
material into the impression
 Set
77

78.  Provisional Restoration
fabricated using composite
resin
 Resin cured
78

79. ADVANTAGES3
 Less time required (rapid setting)
 Ease of removal of interim restoration or inlay.
DISADVANTAGES
 Expensive
 Surface details poor
79

80.  Compared the surface detail production of flexible die material systems with stone
dies and concluded that flexible die material can produce better surface detail
reproduction the die stones.10
 But if separator is used, surface detail reproduction is poor
80
10. Jack D.G. Comparison of the surface detail production of flexible die material systems (JPD 1998;80:485-9)

81. CERAMIC DIES
81
Ceramic: of or relating to the manufacture of any product made essentially
from a nonmetallic mineral (as clay) by firing at a high temperature1 (GPT-9)

82. Powder and liquid Mix in putty consistency and fill in impression Remove
after 1 hour from impression  Fire at 600 oC
 Advantage: Hard, strong die with high abrasion resistance
 Disadvantage: High shrinkage
82

83. Compatibility of cast or Die materials with impression
materials4:
 Cast or die material compatible impression material
 Gypsum products Zinc- oxide eugenol
Alginate
Rubber base material
Impression plaster used by a
separator
Impression compound
83

84. Compatibility of cast or Die materials with Impression materials:
 Electroplated copper Impression compound
 Electroplated silver Polysulfide
Silicones
84

85. Compatibility of cast or Die materials with impression materials3,5:
Epoxy resins
Polysulfide
Polyether
85

86. Surface reproduction of details:
 According to ADA specification no. 25 , the material shall reproduce a
groove 0.050 mm (50 microns) in width.
 According to Ella et al., epoxy resin can reproduce even 1 micron
 Resin modified gypsum- 15 micron and Type IV gypsum -20 microns
 According to Craig, Epoxy dies are best for reproducing detail (10 μm),
followed by high-strength stone dies (170 μm).

87. DIE HARDENER3,11,12
87

88. 88
• Materials applied on the surface of die to increase the
surface hardness.
• It also prevents the die spacer from seeping into the die.
• Should have low viscosity
• Must be applied lightly
• Thickness of cyanoacrylate- 1-2.5 µm
• Thickness of acrylic lacquers- 4 -10 µm
18. Shillingburg HT. Fundamentals of fixed prosthodontics. 4th ed. Quintessence Publishing; 2012.

89. COMMONLY USED MATERIALS AS DIE HARDENERS:
•Resins like
1. Cyanoacrylate resins
2. Acrylic resin lacquer
3. Epoxy resin
4. Styrene
•Colloidal silica
•Gum arabic, calcium hydroxide mixture
89
24. Dykema RW, Goodacre CJ, Phillips RW. Modern practice in fixed prosthodontics. 4th ed. Philadelphia: W B Saunders
Company; 1986.

90.  Applied to finish line area of the die to prevent abrasion by waxing
instruments during the fabrication of wax pattern
 Applied with brush or PKT instrument no 1.
90
19. Fukui H, Lacy AM, Jendresen MD. Effectiveness of hardening films on die stone. J Prosthet Dent 1980:44(1);57-63.

91. Quickly blown off and dried from above
the margin toward the cervical area.
or
Blot with tissue
9119. Fukui H, Lacy AM, Jendresen MD. Effectiveness of hardening films on die stone. J Prosthet Dent 1980:44(1);57-63.

92. 1. Cyanoacrylate resins and resinous die hardeners effectively improved the hardness
and abrasion resistance of stone dies.
2. Application of liquid resins followed by blotting and/or blowing with compressed air
produced an improved surface without clinically significant dimensional change. The
extent of film buildup was qualitatively related to the viscosity of the resin
3. Application of multiple coats of resin without further blotting or other mode of
removal of the excess produced a thick film which can obliterate surface detail
92
12. Lacy AM et al. Effectiveness of hardening films on die stone. J Prosthet Dent. 1980:44:356

93. DIE SPACER1,3,12,13,14,15,16,17
93

94. Die spacer: An agent applied to a die to provide space for the
luting agent in the finished casting1(GPT-9)
This material is applied to the die to increase the cement space
between the axial walls of the prepared tooth and the restoration3.
94

95. 12. Cho SH, Chang WG, Lim BS, Lee YK. Effect of die spacer thickness on shear bond strength of porcelain laminate veneers. J Prosthet Dent 2006;95(3):201-8.
 Die spacer thickness should be adequate enough to allow for proper seating
of a restoration, but not in excess to the extent that a thicker than necessary
cement layer results.
95

96. Various materials used as die spacers
96
DVA spacer DVA spacer –
Blue & red – 12 micrometer Gold & silver – 6 micrometre
Die spacer (Kerr laboratory)
Silver metallic Pactra airplane dope (Pactra industries ,
Calif. )
Pico-fit die spacer (RenfertGermany)
Tru-fit die spacer-(George Taub products)
Lacquer
Finger nail paint

97. Optimal thickness according to various authors
20-40 micro meter (Acc. to rosenstiel 4th edi.)
Rudd and Morrow – 10-15 micro meter
Fusayama et al (JPD 1964;14;95)-thickness should not be less than 30 micro
meter.
Jorgensen et al (JPD 1966:16;740) variations of thickness from 20-140 micro
meter had only moderate influence on retention.
Eames et al (JADA 1978;96;432) – optimal thickness - 25 micro meter
PAGE 97

98. PROPERTIES3
 Should flow uniformly and smoothly
 Color should be readily identifiable on the die
 Thinners are available to decrease the viscosity of die spacer.
98

99.  Brush strokes in one direction
 Wait for 2 mts before applying next coat
 Should be applied 0.5-1mm short of margin
99

100. 100
13. Youtube. Available from: https://www.youtube.com/watch?v=8Nj-Tv2n0zE

101. 101
Should spacer be
applied in the groove
or not?14,15

102. Found that grooves significantly inhibit the seating of castings,
presumably by acting as small hydraulic cylinders during cementation
process. Therefore application of spacer in groove is essential.
102
14. Tjan et al. Effect of multiple axial grooves on the marginal adaptation of full cast-gold crowns. J Prosthet Dent 1981;46;399

103. Grooves should not be die spaced because intimate adaptation of the casting
to the tooth is essential to achieve optimum resistance and retention, and
the die spacer may tend to pool in the groove and hence obliterate much of
the critical detail.
103
15. Donovan T et al. Use of paint-on die spacers in preparations with grooves. J Prosthet Dent 1984;47;606.

104. Grooves did not disrupt seating when die spacer application was
specifically omitted from grooves.
10416. W.V. Campagni et al. effect of die spacer on the seating of complete cast gold crowns with grooves. (JPD 1986;55;324

105. 105
 Following crown fabrication  easily removed
and a final check for fit is made on the original
clean die.
25 microns of space.
Advantage:
 Eliminates see-through of undesirable die spacer
color under all ceramic crowns
 Allows true verification of fit to the original die
form
PEEL-AWAY DIE SPACER

106. PAGE 106

107. 107
Die Spacer Pens3 (Kerr Laboratory)
Poly fiber disposable tip.

108. DIE SEPARATORS
 The lubricants or die separators which can be used to
prevent wax from adhering to stone are oils, liquid
soap, detergents and a number of commercially
available preparation.
PAGE 108

109. PAGE 109

110. PREPARATION OF DIE18,24,25
110
18. Shillingburg HT. Fundamentals of fixed prosthodontics. 4th ed. Quintessence Publishing; 2012.
24. Dykema RW, Goodacre CJ, Phillips RW. Modern practice in fixed prosthodontics. 4th ed. Philadelphia: W B Saunders
Company; 1986.
25. Tanquist RA. Die trimming : a guide to physiologic contour. J Prosthet Dent 1982;48(8):485-9.

111. Ditching the Die16
 Ditching or trimming the die defines the position of the margin and acts
as a guide to gingival contour when the restoration is being waxed.
 Excessive trimming does not give the correct emergence profile and may
lead to an over-contoured or bulky crown.
111

112.  Pear shaped acrylic bur
trimmed apical to finish line
 Final trimming sharp blade
 Smoothened
112

113. 113

114. 114

115. 115

116.  Contour be approximately like root
 To facilitate good axial contours
in restoration
116

117.  Finish line highlighted with red pencil
 Not to use black graphite pencil
 Apply die spacer
117

118. 118

119. DIE SYSTEMS3,16
119

120. .Shillingburg HT. fundamentals of fixed prosthodontics. 3rd ed. Quintessence Publishing
Working cast with separate die
Working cast with removable die
 Working cast or definitive cast or master cast is the replica of the
prepared teeth, ridge areas and other parts of dental arch.
120

121. Working cast with separate die
Simplest method of fabrication
121
.ShillingburgHT.fundamentalsoffixedprosthodontics.3rded.QuintessencePublishing

122. ADVANTAGES
•Easy to fabricate
•Keeps relation between abutments fixed & immovable
•Better contours and emergence profile while wax pattern fabrication.
122

123. DISADVANTAGES
 Wax pattern must be transferred from die to cast  destroy internal
adaptation of wax
 Some times difficult to seat wax pattern on the cast
- Different impressions
- Second pour –impression damaged
 Can be used only with elastomeric impressions
123

124. WORKING CAST WITH REMOVABLE DIE 3,18
124

125. The die is an integral component of the definitive cast and
can be lifted from the cast to facilitate access3
Precise relocation of the die is crucial to this system’s
success3
Brass pins or dowels used
125
Rosensteil SF, Land FM, Fujimoto J. Contemporary fixed prosthodontics.3rded. St.Louis:Mosby;2001

126. Advantages:
 Convenient to use
 Reduced chance of breakage during transfer
 Various drawback of separate die are overcome
Disadvantage::
 Risk of introducing error in the pattern if die does not seat accurately in the
working cast
 Difficulty in sawing the die out of cast
126

127. The cast is made in two pours of type IV or V stone of
contrasting colors : the first forms the teeth and the second
forms the base of the cast. The area to be removed is coated
with the separating media before the second layer is
produced.
PAGE 127

128. Requirements:
1) Dies must return to their exact original position
2) Dies must remain stable even when inverted
3) Cast containing dies must be easy to mount on an articulator.
128

129. CONVENTIONAL DOWEL PIN SYSTEM
DI-LOK
PINDEX
DVA
BELLE DE ST. CLAIRE
ZEISER
ACCU-TRAC SYSTEM
MONO TRAC
129
OTHER DIE SYSTEMS :

130. 130
Pre pour technique
Devices are
oriented in the
impression before
it is poured
Post pour technique
Attached to the
underside of the cast
that has already been
poured
Pre pour technique
Devices are
oriented in the
impression before
it is poured
Post pour technique
Attached to the
underside of the cast
that has already been
poured
Methods of repositioning die in its working cast

131. Dowel pin : a metal pin used in stone casts to remove die
sections and replace them accurately in the original position
131
DIMENSIONS:
length – 23 mm
taper – 18 mm
head – 5 mm

132. 132
Straight Curved

133.  Double straight dowel with
common head (Bi pin)
 Rounded single dowel pin
 Flat sided dowel
133

134. Euro Pin (Cori Dent)
134
Extended pin head

135. Procedure18
(Pre-pour technique)
135
18. Tjan et al. Effect of multiple axial grooves on the marginal adaptation of full cast-gold crowns. J Prosthet Dent
1981;46;399

136. 1. Positioning of dowel pins
 Marking to act as guide in placement of pins
136

137. 2. Paralleling instrument - for alignment of dowel pins
137
Mann paralleling instrument Clamps holding Dowel pins

138. 138
Devices to position dowels before pouring impression:
needles and pins,
 paper clips,
bobby pins,
wax wafers,
Match sticks
Balshi et al. Matches, clips, needles or pins. J Prosthet Dent 1975;34(4):467-72.

139. Disposable needles
139

140. Straight pins with modeling clay . Matchsticks
140

141. 6. Bobby pins27
141

142. 142
Die stone poured into impression filling the impressions of
teeth and covering the knurled end of the dowel pin

143. 143
V- shaped orientation
grooves made
Separating media-area
adjacent to each
dowel pin

144. 144
Small wax ball placed
on tip of each dowel
Boxing done
Base formed

145. 145

146. 146
The intended saw cuts are marked in pencil, and the saw blade
is carefully positioned. It must not
touch the prepared tooth.
The first pour is sawed completely through. Finishing the cut
short of the second pour will prevent a
clean separation.

147. 147

148. Curved dowel pin
148
Positioning bar
Stone poured covering heads of
dowel and 1-2mm of body of
dowel

149. 149
Orientation grooves made

150. 150

151.  Thin metal strips(.001
gauge)were carefully
wedged in the
impression
151
Using metal strips

152. 152
Placement and tapering
of matrix band
Matrix band kept parallel in case of multiple
preparations

153. 153
2 mm of band exposed

154. Post pour techniques
154

155. Two pours: (contrasting colors)
155
1) Forms the teeth 2) Forms the base
Rosensteil SF, Land FM, Fujimoto J. Contemporary fixed prosthodontics.3rded. St.Louis:Mosby;2001

156. PAGE 156

157. DIE SYSTEMS3,18,19,20
157

158. Di - Lok tray system3,19.
(Di –Equi Dental products Co)
158Miranda et al. Comparative stability of two removable die systems: J Prosthet Dent 1976;36;326

159. The full-arch Di-Lok tray can be disassembled into
three pieces:
159
1) the body of the tray which establishes arch
curvature

160. The full-arch Di-Lok tray can be disassembled into
three pieces:
160
2) outer tray perimeter which confines the poured
base to this curvature

161. The full-arch Di-Lok tray can be disassembled into
three pieces:
161
3) posterior locking bar which stabilizes the assembly
as a unit

162. The first two pieces are ribbed so that when the base is poured
the entire cast-base system has stability and accuracy 
during reassembly
The initial cast must be trimmed to fit the space provided in
the tray
The trimmed cast is then notched on its sides so as to provide
additional retentive locks for the stone base
162

163. The cast is placed into the space provided in the tray, and a
base of stone is poured
Once material sets, the tray can be disassembled and the
cast removed for production of dies
163

164. A, With a single-pour technique, the impression is formed in the usual way, and the Di-Lok tray
is filled. Then the tray is inserted into the impression while the stone is still wet.
B, After the die stone has fully set, the locking and curved arms of the tray are removed. The
cast can then be removed by tapping the anterior pad of the tray base
164

165.  A handsaw is used to section upto 3/4th through the
stone
 Gentle finger pressure is used to “snap” the dies
apart,
 leaving a small area of stone surface on each
segment that can be intimately joined to adjacent
units during reassembly
165

166.  Trimmed dies.
Assembled cast ready for articulating.
166

167. Advantages3
 Use of a specially articulated tray for precise reassembly of sectioned
definitive cast
 Cast pouring unimpeded
 Less costlier than Pindex
167
Disadvantage3
 Overall size of the tray can make articulation and manipulation difficult.

168. PINDEX SYSTEM3 (Coltene /Whaledent)
168

169. The Pindex system is composed of a precision
drill mechanism (aligned drill and light
source), dowel pins, and corresponding
precision plastic sleeve
169

170. 170
Base should be flat to ensure
that the Pins will be parallel
Facio-lingual width – 20 mm

171. 171
 working cast is placed on the drill
table
 oriented until the light beam in the
drill unit is directed to the desired
point (occlusal surface of the
proposed die)

172. 172

173. 173
Apply cyanoacrylate cement on the ends of dowel pin and place it into the
prepared portion of base of die

174. 174
Shorter pins on lingual side
Longer on buccal side makes the ends of the dowel pins more accessible
for easy removal after the casts are mounted.
Collar of the pin should
be flush with the base.

175. 175
Plastic sleeve inserted.

176. 176
 The cast is then placed in a die
base former and the base is
poured in dental stone

177. 177

178. 178
 Die cutting machine
 Blade thickness: 0.2-0.3 mm

179. 179
Carefully insert the saw blade between the preparation & adjacent tooth
Saw cuts should be parallel or slightly converge towards base.

180. Advantages Disadvantages
 Removable die
 Cast pouring unimpeded
 Special equipment needed
 Costly
180

181. Serrano et al. An accuracy evaluation of four removable die systems. J Prosthet Dent 1998;80:575-86.
 This study evaluated the 3-dimensional accuracy of 4 removable die
systems:
 Belle de St. Claire
 Pindex
 DVA
 conventional brass dowel system
181

182. Serrano et al. An accuracy evaluation of four removable die systems. J Prosthet Dent 1998;80:575-86.
 All 4 die systems provided a similar degree of dimensional accuracy,
although Pindex showed the least horizontal movement and the brass
dowel system produced the least occlusogingival reseating discrepancy.
182

183. DVA system3
 The DVA Precision Model System produces totally poured and pinned
models and dies in only one pour.
 Fast, simple to use, and clean method of producing dies and models of
maximum cross-arch accuracy.
 This precision system compensates for the normal, distorting linear
expansion experienced by die stones during setting.
183

184. DVA system3
 The DVA Precision Model System includes:
 a specially designed Pin Alignment and Drilling Machine, which
determines dowel pin locations prior to the pouring of the model;
pre-manufactured Base Plates;
specially designed dowel pins.
Arch-Trimming Machine, with its own built-in vacuum and dust
collection systems
184

185. A, Trimmed impression on alignment fixture. B, Marking dowel pin locations on clear plate
185

186.  C, Drilling holes for dowel pins as marked.
 D, Inserting dowels in the baseplate. An adhesive is not required
186

187. F, G, Set cast is removed from baseplate &
trimmed.
187
E, The impression is poured, stone is placed around
dowel pins, and the alignment fixture is replaced
over poured impression.
H, Cast is trimmed.

188. Advantages Disadvantages
 Compensates for expansion of
cast
 Single pour needed
 Removable die
188
• Special equipment needed
• Quite technique sensitive

189. Zeiser model system3
(Girrbach dental Gmbh, Germany)
189

190. 190
 The impression is leveled, blocked out
with silicone putty, and positioned over
the baseplate.

191. 191
Pin locations determined Pin holes drilled in base

192. 192
Pins inserted into base

193. 193
Base inverted and separated

194. 194
The sectioned cast

195. Advantages Disadvantages
 Compensates for expansion of
cast
 Single pour needed
 Removable die
195
• Special equipment needed

196. Accu- Trac Die Precision System (Coltène Whaledent)
196
-
https://www.coltene.com/fileadmin/Data/EN/Products/Laboratory/Modelmaking/Accu-Trac_Model_System/ACCUTRAC

197. Accu- Trac Die Precision System (Coltène Whaledent)
197
-
The ACCU-TRAC System makes the fabrication of
precision models and dies easier.
The model and base are poured as one, eliminating
the additional work when using pins and sleeves.
Saves time & material & is precise

198. 198

199. 199

200. 200

201. 201

202. 202

203. ADVANTAGES
 One universal tray size
 Low base height
 One pour technique
 Economical
 Numerical die location
 Open bottom tray
203

204. TROUBLE SHOOTING13 (Rudd & Morrow)
 PROBLEM:
204
Voids or bubbles
in cast
Stone not vacuum
mixed
Stone added to
impression too
rapidly

205. TROUBLE SHOOTING13 (Rudd & Morrow)
 PROBLEM:
205
Removable dies
fracturing at neck
Dowel pin placed
too deep in
impression
Die ditched too
deeply

206. TROUBLE SHOOTING13 (Rudd & Morrow)
 PROBLEM:
206
Removable die
rotating in
working cast
Dowel pin too
short in base of
cast
Base of die
lacking positive
seat

207. TROUBLE SHOOTING13 (Rudd & Morrow)
 PROBLEM:
207
Unable to remove
dies after saw
cuts are made
Saw cuts not
tapered
Adjacent natural
teeth restricting
removal of die

208. TROUBLE SHOOTING13 (Rudd & Morrow)
 PROBLEM:
208
Removable die
unable to seat
completely on die
Debris in pinhole,
on pin, on base,

209. Dies for CAD CAM systems30
30. Christensen GJ. Will Digital Impressions Eliminate the Current
Problems With Conventional Impressions. Canadian Journal of
Restorative dentistry and prosthodontics 2009 209

210. Problems with conventional methods30
210
Remake dies
digital impression concept allows retention of
the digital information in appropriate computer
storage as soon as it is received

211. CERECSYSTEM
(SironaDental
System,
Germany)
211

212. 212
INTRAORAL CAMERA TO TAKE
OPTICAL IMPRESSION OF THE
PREPARATION

213. 213
PREPARATION COVERED
WITH OPAQUE POWDER
( Titanium dioxide )

214. 214
Image as
viewed on monitor Cavity outlines are identified for
formation of future restoration

215. 215
Cerec milling unit

216. PROCERA ALL CERAM SYSTEM
(Nobel Biocare)
216

217. 217
Scanning of the die
Scanner probe with a
ball tip

218. 218
Displayed image

219. 219
•Spacer thickness programmed
•Designing of the restoration done

220. 22031. Youtube. Available from: https://www.youtube.com/watch?v=L6Ornv6a79w

221. CONCLUSION
221

222. REFERENCES
1. The Glossary of Prosthodontic Terms. J Prosthet Dent 2005 Jul;94(1):10-92.
2. Phillips, RW. Skinner’s science of dental materials. 11th ed., Philadelphia: The WB Saunders Co;
1982.
3. Rosensteil SF, Land FM, Fujimoto J. Contemporary fixed prosthodontics. 3rd ed. St.Louis: Mosby;
2001.
4. Craig RG. Restorative dental materials. 9th ed. St. Louis: Mosby; 1993.
5. Mason HJ. Impregnation of stone dies with acrylic resin. J Prosthet Dent 1970;23:96-8.
222

223. REFERENCES
6. Myers GE. Electroformed die technique for Rubber base impressions. J Prosthet
Dent 1958;8:531-5.
7. Crispin et al. Silver-plated dies. Part II: Marginal accuracy of cast restorations. J
Prosthet Dent 1984;51(6):768-73.
8. Cassimaty EM et al. Effect of three variables on the accuracy and variability of
electroplated copper dies. Int J Prosthodont 1996; ;9(6):547-54.
9. Gerrow JD , Price RB. Comparison of the surface detail reproduction of flexible
die material systems. J Prosthet Dent 1998;80(4):485-9.
223

224. REFERENCES
10. O’Briene WJ. Dental materials and their selection. 3rd ed. Quintessence Publication; 2002.
11. McCabe JW, Walls AWG. Applied dental materials. 8th ed. Blackwell Science; 1998.
12. Cho SH, Chang WG, Lim BS, Lee YK. Effect of die spacer thickness on shear bond strength of porcelain
laminate veneers. J Prosthet Dent 2006;95(3):201-8.
13. Morrow RM, Rudd KD, Rhoads JE. Dental laboratory procedures fixed partial dentures. 2nd ed. USA
Mosby;1986
14. Eames WB, G’Neal SJ, Monteiro J, Miller C, Roan JD Jr, Cohen KS. Techniques to improve the seating of
castings. J Am Dent Assoc 1978;96:432-7.
15. Fusayama T, Ide K, Hosada H. Relief of resistance of cement of full cast crowns. J Prosthet Dent 1964;14:95-
106.
16. Bassett RW. Solving the problems of cementing the full veneer cast gold crown. J Prosthet Dent
1966:16(4);740-7. 224

225. REFERENCES
17. Campagni WV, Preston JD, Reisbick MH. Measurement of paint-on die spacers used for casting relief. J
Prosthet Dent 1982;47:606-11.
18. Shillingburg HT. Fundamentals of fixed prosthodontics. 4th ed. Quintessence Publishing; 2012.
19. Fukui H, Lacy AM, Jendresen MD. Effectiveness of hardening films on die stone. J Prosthet Dent
1980:44(1);57-63.
20. Li-Hong et al. A micro-mechanical evaluation of the effects of die hardener on die stone. Dental Materials
Journal 2010;29(4): 433–7.
225

226. REFERENCES
21. Miranda FJ, Diltis WE, Duncanson MG, Collard EW. Comparative stability of two removable die
systems. J Prosthet Dent 1976;36(3):326-33.
22. Serrano et al. An accuracy evaluation of four removable die systems. J Prosthet Dent 1998;80:575-
86.
23. Sivakumar et al. A comparison of the accuracy of three removable die systems and two die materials.
European Journal of Prosthodontics and Restorative Dentistry 2013;21(3):115-9.
24. Dykema RW, Goodacre CJ,Phillips RW. Modern practice in fixed prosthodontics. 4th ed. Philadelphia:
W B Saunders Company; 1986.
25. Tanquist RA. Die trimming : a guide to physiologic contour. J Prosthet Dent 1982;48(8):485-9.
226

227. REFERENCES
22. Li-Hong et al. A micro-mechanical evaluation of the effects of die hardener on die stone. Dental
Materials Journal 2010; 29(4): 433–437.
23. Shillingburg HT. fundamentals of fixed prosthodontics. 3rd ed. Quintessence Publishing
24. Available at: http://www.usdentaldepot.com
25. Millstein P. A Comparison of Two Die Systems Using Prepour and Postpour Pin Placement.
Quintessence of Dental Technology 2004:195-200.
26 Comparative stability of two removable die systems: J Prosthet Dent 1976;36;326
27. Serrano et al. An accuracy evaluation of four removable die systems. J Prosthet Dent 1998;80:575-86.
28. Sivakumar et al. A comparison of the accuracy of three removable die systems and two die materials.
European Journal of Prosthodontics and Restorative Dentistry 2013;;21(3):115-119.
29. Available at: http://whipmix.com/wp-content/uploads/via-product-catalog/product_docs/Gypsum
30. Christensen GJ. Will Digital Impressions Eliminate the Current Problems With Conventional
Impressions. Canadian Journal of Restorative dentistry and prosthodontics 2009.
31. Available at: https://www.youtube.com/watch?v=L6Ornv6a79w
227