die system

1. DIE AND DIE SYSYTEM
Dr.shiva sai vemula
1st year MDS
Dept.of PROSTHODONTICS
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2. CONTENTS
• DIE:-
• INTRODUCTION
• TERMINOLOGY
• CLASSIFICATION
• IDEAL PROPORTIES
• DIE (HARDNER,SPACER AND LUBRICANT)
• DIE SYSYTEM:-
• CLASSIFICATION
• DI LOC TRAY SYSTEM
• PINDEX SYSTEM
• DVA SYSTEM
• ZEISER MODEL SYSTEM
• MONOTRAC ARTICULATION SYSTEM
• DIE PINS 2

3. Direct fabrication of extra coronal restoration in the
mouth is inconvenient, difficult, time consuming and
virtually impossible. A cast and die system captures
the necessary information so that can be transferred
to the laboratory.
An accurate working cast with removable dies is
essential to make a well fitting restoration.
INTRODUCTION
3

4. Die :- It is the positive reproduction of the form of
the prepared tooth in any suitable substance.
Cast :- A life-size likeness of some desired form. It
is formed within or is a material poured into a
matrix or impression of the desired form
Dowel pin:- A metal pin used in stone casts to
remove die sections and replace them accurately
in the original position
4

5. MATERIALS USED FOR
MAKING DIES
NON
METALLIC
METALLIC
• Gypsum materials
• Cements(Silicophospate cement)
• Refractory die materials
• Polymers (epoxy resin, polyurethane)
• Electroformed dies
• Amalgam
• Sprayed metals
5

6. 6
Hydrocal
Densite
Crystocol
impression

7. Ideal properties
• It should be dimensionally accurate.
• It should have high abrasion resistance and smooth
surface.
• Toughness:- it should resist to breakage (burnishing
foil)
• Ability to reproduce all the fine details in the
impression.
• Compatibility with all the impression material.
• Easy and quick manipulation and rapid fabrication.
• Non toxic.
• Ecominical
7

8. ADA TYPE 4
stone
•Dimensional
accuracy Most
situations
Accurate
proportioning
Eessential
• Straight
forward
Technique
• Low cost
Low abrasion
resistance
ADA TYPE 5
stone
•Straight
forward
technique
Increased
expansion
Base metal
alloy
situations
Accurate
proportioning
essential
• Low cost
•Improved
strength than
type4
Materials Advantages Disadvantage Use Precaution
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NON METALLIC

9. Materials Advantages Disadvantage Use Precaution
Electroplating High strength
Good abrasion
resistance
•Time
consuming
Complete
ceramic
crowns
•Silver uses
toxic cyanide
•Incompatible
with many
impression
materials
Amalgam •High strength
•Good abrasion
resistance
• low setting
time
• high thermal
conductivity(
wax pattren
will cools
fast-
distertion)
Complete
ceramic
crowns
9
METALLIC

10. A low viscosity
polyvinyl siloxane
duplicating
material is used to
reproduce dies
Adapt a strip of
putty around the
prepared teeth on
working cast and
dies to limit the flow
of mold material.
RefractoryDies:-
These are made for preparation of all ceramic restorations.
Advantages – Excellent marginal adaptation
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11. • The duplication material should be at least 3.00mm thick and it
should extend 3 mm beyond incisal edges of teeth to provide
adequate support refractory material.
• The duplicating material is allowed to set for about 30 minutes.
• The master dies removed
from cast and duplicating
material.
By applying pressure on
base of tray, master cast is
loosened with duplicating
material intact.
11

12. Allow the refractory
dies set for about 1-2
hours.
The refractory material
is poured and vibrated in
the area of missing dies.
12

13. Die Hardener
• Materials applied on the surface of die to
increase the surface hardness.
• Should have low viscosity
• Commonly used materials as die
hardeners:
 Cyanoacrylate resins (Eg: Premabond)
 Acrylic resin lacquer (Eg: Die Prep die hardener)
• Optimal Thickness  2-3 mm, but if not properly
manipulated10 mm
13

14. Die Spacer :-
An agent applied to a die to provide space for the
luting agent in the finished casting.
Types of die spacers :
• Resins
• Paint or liquids
• Model paint
• Coloured nail polish
• Thermoplastic resins dissolved in volatile solvents.
14

15. Should be applied
0.5-1mm short of margin
Brush strokes in one direction
Wait for 2 mins before
applying next coat
• W.V.Campagni et al (JPD 1986;55;324) concluded that grooves did
not disrupt seating when die spacer application was specifically
omitted from grooves
• Optimal thickness:-20-40 micro meter
15

16. die lub
Die Separator
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
preparations.
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17. Cast & Die
Systems
17

18. Die systems
Working cast
with separate
die
Working cast
with
removable die
Without die
pins
With die pins
Pre pour
technique
Post pour
technique
18

19. Working cast with separate die
Method of
Simplest
fabrication
between
Advantages:
• Easy to fabricate
Keeps relation
abutments fixed.
• Better contours and
emergence profile while
wax pattern fabrication. 19

20. 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
- Different thickness of spacers
Procedure:-
Both working cast and sectional die can be obtained by:
- Pouring impression twice
- Making two impressions 20

21. Trim sectional cast
Octagonal in shape
Sides parallel or slightly
taper towards base
Handle 1 inch long
Pear shaped acrylic bur
 trimmed apical to finish line
21

22. Contour be approximately like root 
To facilitate good axial contours in
restoration
Philippe A. et al (IJP 1993:6;533) compared 2 removable die systems
(Zeiser system (Girrbach Dental), Pindex (Coltene-Whaledent) and
working cast with separate die. They concluded that the Zeiser system
was the most accurate of the three systems studied, followed by
working cast with separate die.
22

23. WORKING CAST WITH REMOVABLE DIE
Advantage:
Convenient to use
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
23

24. 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
24

25. WORKING CAST WITH REMOVABLE DIE
working cast with die pins preformed plastic trays
working cast without die pins
25

26. 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
Systems using die pins
26

27. Pre pour technique
27

28. Procedure
Positioning of dowel pins
A) Marking to act
as guide in
placement of pins
Mann paralleling instrument
Clamps holding
Dowel pins
B)
28

29. C) Disposable anesthetic needles
D) Straight pins with
modeling clay
E) Matchsticks
F) Bobby pins
29

30. Die stone impression poured into filling the of teeth and
covering the knurled end of the dowel pin
V- shaped orientation
grooves made
Separating media-area
adjacent to each dowel pin
Small wax ball placed
on tip of each dowel
30

31. 31

32. Using metal strips
Thin metal strips (0.001 gauge) were
carefully wedged in the impression
Placement and tapering
of matrix band
Matrix band kept parallel
in case of multiple
preparations
2 mm of band exposed
32

33. Post pour techniques
33

34. Di lok tray system
34

35. Snap apart plastic tray with internal orienting
grooves and notches to reassemble the working
cast and die.
Before using check for
space in articulator
Cast poured1inch
height
Trim to fit Di lok tray
35

36. Fill tray ¾ with stone
Seat the cast  cervical area
of teeth be about 4mm above
the edge of tray
Disassemble the
tray 36

37. 37

38. PINDEX SYSTEM
(Coltene / Whaledent)
Light beam
director
Work table
Drill hole
Handle bar
Motor housing
38

39. Bottom should be flat to ensure that the
Pins will be parallel Faciolingual width – 20 mm
Two pins for each die
Two for each pontic area
One /Two pins in each terminal
segment containing unprepared
teeth
39

40. 40

41. 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.
Ends of shorter sleeves  place wax
41

42. 42

43. DVA System
(dental ventures of america)
Pre manufactured base system
43

44. Marking dowel pin locations On clear
plate with twin tip marker
Impression on alignment fixture
Secured with putty
Drill holes for dowel pins
Using drilling press
44

45. Insert dowel pins Impression is poured and stone
is placed around dowel pin
Alignment fixture is replaced over
poured impression
Set cast is removed from
baseplate with gentle tapping
45

46. Cast is trimmed Cast is sectioned
Definitive cast trimmed with
DVA model system 46

47. 47

48. Zeiser model
system
48

49. Impression leveled, blocked out
with silicone putty
positioned over the base
Pin locations determined Pin holes drilled in base
49

50. Pins inserted into base Impression is poured
Base inverted The cast is separated
from the impression 50

51. Monotrac Articulation
Vertical single pour base (VSP) Pour stone
Spray silicone spray on VSP
Cones.
Separator on stone
51

52. Trim impression –fit the
base molds
Pin –act as guide for placement
52

53. Remove base mold
and impression
VSP base removed by tapping
53

54. 54

55. Conventional dowel pin systems
Dowel pin (GPT 8): a metal pin used in stone
casts to remove die sections and replace them
accurately in the original position
Straight Curved
55

56. Straight dowel pins
Flat sided
dowel
Double straight
dowel with
common head
(Bi pin)
Rounded single
dowel pin
BI-PIN with case
BI-FIXED-pin
Doubles straight dowel
with fixing wire for
accurate positioning
in impression 56

57. 57
REFRENCES
• Anusavice K.J.-“Phillips’Science of Dental materials” 11th edition ,
2003
• Craig’s R.G., Powers J.M. – “Restorative Dental Materials”
11thedition, 2002
• RosenstielS.F., Land M.F.–“Contemporary fixe prosthodontics”
3rd edi. 2001.
• Rudd K.D., Morrow R.M. – “Dental laboratory procedures” FPD
2nd edi, 1986.
• Shillingburg H.T. – “Fundamentals of fixed Prosthodontics.”3rd
edition
• Juan Glen Serrano, Xavier Lepe, John D. Townsend, Glen H. Johnson,
Stephen Thielke-An accuracy evaluation of four removable die
systems-J Prosthet Dent 1998;80:575-86.
• C, Douglass Smith,Arun Nayyar, David L. Koth-Fabrication of
removable dies using cemented dowel pins J Prosthet Dent:
1992:68:372-4

58. Thank you
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