Inlay_Casting_Wax-BDS_II_Year-31-12-14.ppt

Casting waxes are important material to prepare a cast.

1. Dr. Raghuwar D Singh
Associate Professor
Prosthodontic Department
King George’s Medical University UP, Lucknow
Dental Materials Lecture
BDS II Year

2. 
First procedure in the casting of an inlay or First procedure in the casting of an inlay or
crown is the preparation of a wax pattern.crown is the preparation of a wax pattern.

TECHNIQUES for WAX PATTERN TECHNIQUES for WAX PATTERN
Preparation::Preparation::
** Direct Technique Direct Technique
** Indirect Technique Indirect Technique

3. 
TYPES OF INLAY CASTING WAX --TYPES OF INLAY CASTING WAX --
** According to ADA Specification No. 4 ::According to ADA Specification No. 4 ::
TYPE I = Medium Wax for Direct TechniqueTYPE I = Medium Wax for Direct Technique
TYPE II = Soft Wax for Indirect Technique TYPE II = Soft Wax for Indirect Technique

4. COMPOSITIONCOMPOSITION

Paraffin wax = 40 to 60 %Paraffin wax = 40 to 60 %

Gum dammar Gum dammar

Carnauba waxCarnauba wax

Coloring agent Coloring agent

5. 
PARAFFIN WAX : PARAFFIN WAX :
** Derived from high boiling fraction of petroleum.Derived from high boiling fraction of petroleum.

** Depending upon Molecular Wt. & Distribution Depending upon Molecular Wt. & Distribution
can be obtained in a wide melting or softening can be obtained in a wide melting or softening
range.range.
** Paraffin used for Type I waxes have higher Paraffin used for Type I waxes have higher
melting point than the Paraffin used for Type II melting point than the Paraffin used for Type II
waxes.waxes.

6. DISADVANTAGES –DISADVANTAGES –

Flake when it is trimmed.Flake when it is trimmed.

Does not present Smooth, Glossy surface.Does not present Smooth, Glossy surface.

7. 
GUM DAMMAR or DAMMAR RESIN :GUM DAMMAR or DAMMAR RESIN :

Natural Resin.Natural Resin.

Added to improve the smoothness in molding.Added to improve the smoothness in molding.

Resistant to Cracking & Flaking.Resistant to Cracking & Flaking.

Increases the Toughness of the wax.Increases the Toughness of the wax.

Enhances the Smoothness of the surface.Enhances the Smoothness of the surface.

8. 
CARNAUBA WAX :CARNAUBA WAX :

Occurs as fine powder.Occurs as fine powder.

Quite Hard in nature.Quite Hard in nature.

High Melting point.High Melting point.

Combined with paraffin to Decrease the flow Combined with paraffin to Decrease the flow
at mouth temperature.at mouth temperature.

Give more Glossiness to wax surface than Give more Glossiness to wax surface than
dammar resin.dammar resin.

9. CANDELILLA WAX CANDELILLA WAX can also be added to can also be added to
replace the Carnauba wax. replace the Carnauba wax.

Its Melting point is lower.Its Melting point is lower.

Not as hard as Carnauba wax.Not as hard as Carnauba wax.
CERESINCERESIN may replace part of Paraffin to modify may replace part of Paraffin to modify
the toughness & carving characteristics of wax. the toughness & carving characteristics of wax.

10. 
In modern Inlay Waxes, the Carnauba Wax is In modern Inlay Waxes, the Carnauba Wax is
often replaced in part with certain Synthetic often replaced in part with certain Synthetic
Waxes that are compatible with Paraffin wax.Waxes that are compatible with Paraffin wax.
Two waxes of this Types are ::Two waxes of this Types are ::

Complex Nitrogen derivatives of higher fatty Complex Nitrogen derivatives of higher fatty
acids.acids.

Esters of acids derived from Montan wax.Esters of acids derived from Montan wax.

11. PROPERTIES OF INLAY WAXPROPERTIES OF INLAY WAX

When softened wax should be uniform.When softened wax should be uniform.

Color should contrast with the die material.Color should contrast with the die material.

No Flakiness or similar surface roughness No Flakiness or similar surface roughness
when wax is bent & molded after softening.when wax is bent & molded after softening.

12. 
Should Vaporize completely during burnout Should Vaporize completely during burnout
(500(500
00
c).c).

Wax should not pull or chip during carving.Wax should not pull or chip during carving.

Wax pattern should be completely rigid & Wax pattern should be completely rigid &
dimensionally stable.dimensionally stable.

13. 
FLOWFLOW

THERMAL PROPERTIESTHERMAL PROPERTIES

WAX DISTORTIONWAX DISTORTION

MANIPULATION OF INLAY WAXMANIPULATION OF INLAY WAX

OTHER DENTAL WAXESOTHER DENTAL WAXES

14. 
FLOWFLOW – –
Requirements according to ADA Specification no. 4,Requirements according to ADA Specification no. 4,
At 45At 45
00
C -- Both Type I & II should have a flow b/w C -- Both Type I & II should have a flow b/w
70 to 90 %.70 to 90 %.
At 37At 37
00
C -- Type I should not flow more than 1 %.C -- Type I should not flow more than 1 %.
At 30At 30
00
C -- Type II should not flow more than 1 %.C -- Type II should not flow more than 1 %.

15. 
THERMAL PROPERTIESTHERMAL PROPERTIES – –

THERMAL CONDUCTIVITYTHERMAL CONDUCTIVITY : :

Low. Low.

Takes time to heat the wax uniformly.Takes time to heat the wax uniformly.

16. 
COEFFICIENT OF THERMAL EXPANSION COEFFICIENT OF THERMAL EXPANSION ::

High.High.

Thermal changes are higher than any other Thermal changes are higher than any other
materials.materials.

Linear expansion of 0.6 % when heated from 25Linear expansion of 0.6 % when heated from 25
to 37to 37
00
C is permitted for Type I waxes.C is permitted for Type I waxes.
This property is more significant in Direct Tech.This property is more significant in Direct Tech.

17. ** Other Factors that influence the Coefficient of Other Factors that influence the Coefficient of
Thermal Expansion are –Thermal Expansion are –

Temperature of the Die.Temperature of the Die.

Method used for applying pressure to the wax.Method used for applying pressure to the wax.

18. 
WAX DISTORTION –WAX DISTORTION –

Most serous problem in Inlay wax.Most serous problem in Inlay wax.

It is due to Release of Stresses in pattern due to,,It is due to Release of Stresses in pattern due to,,
* Contraction on cooling.* Contraction on cooling.
* Occluded gas bubbles.* Occluded gas bubbles.
* Change of shape of wax during moulding.* Change of shape of wax during moulding.
* From Manipulation, Carving, Pooling & * From Manipulation, Carving, Pooling &
Removal.Removal.

19. 
CAUSES OF DISTORTIONCAUSES OF DISTORTION : :

If wax is not at uniform temp. when inserted in the If wax is not at uniform temp. when inserted in the
cavity.cavity.

If wax is not help under uniform pressure during If wax is not help under uniform pressure during
cooling.cooling.

If wax is added in an area of deficiency.If wax is added in an area of deficiency.

20. 
TO AVOID DISTORTION OF WAXES :TO AVOID DISTORTION OF WAXES :

Minimal carving & change in temperature.Minimal carving & change in temperature.

Minimal Storage of pattern.Minimal Storage of pattern.

Use warm instrument for carving.Use warm instrument for carving.

Store it in a Fridge if necessary.Store it in a Fridge if necessary.

21. MANIPULATION OF MANIPULATION OF
INLAY WAXINLAY WAX

TECHNIQUES –TECHNIQUES –

DIRECT TECHNIQUEDIRECT TECHNIQUE

INDIRECT TECHNIQUEINDIRECT TECHNIQUE

22. 
DIRECT TECHNIQUE ::DIRECT TECHNIQUE ::


Softened the stick of wax over the flame.Softened the stick of wax over the flame.

Inserted into the cavity & held under finger Inserted into the cavity & held under finger
pressure.pressure.

Allow to cool gradually at mouth temperature.Allow to cool gradually at mouth temperature.

Withdraw the wax pattern carefully.Withdraw the wax pattern carefully.

23. 
INDIRECT TECHNIQUE ::INDIRECT TECHNIQUE ::

Pattern is prepared over a lubricated die.Pattern is prepared over a lubricated die.

If molten wax used, very little stresses occur.If molten wax used, very little stresses occur.

24. METHODS OF INDIRECT TECHNIQUE –METHODS OF INDIRECT TECHNIQUE –

Dipping Method – Dipping Method –
* In full crowns.* In full crowns.
* Die is dipped in hot liquid wax.* Die is dipped in hot liquid wax.

Softening In Warm Water – Softening In Warm Water – Not recommended.Not recommended.


Adding in Layer – Adding in Layer – Using spatula orUsing spatula or brush.brush.

25. OTHER DENTAL WAXESOTHER DENTAL WAXES

26. 
RPD WAXESRPD WAXES

PRECESSING WAXESPRECESSING WAXES
* Boxing & Beading Waxes.* Boxing & Beading Waxes.
* Utility Wax.* Utility Wax.
* Sticky Wax.* Sticky Wax.

IMPRESSION WAXESIMPRESSION WAXES
* Corrective impression Wax* Corrective impression Wax
* Bite Registration Wax* Bite Registration Wax

27. RPD WAXESRPD WAXES
USES –USES –

To make patterns of metallic framework of RPD.To make patterns of metallic framework of RPD.

Pattern for RPD is made on a special cast known as the Pattern for RPD is made on a special cast known as the Refractory CastRefractory Cast..

28. 
SUPPLIED AS --SUPPLIED AS --
** Sheets Sheets .40 and .32 mm thickness. .40 and .32 mm thickness.
** Readymade shapesReadymade shapes, Round, Half round, Round, Half round
Grid or MeshformGrid or Meshform
Clasp shapesClasp shapes
Other forms.Other forms.
** Bulk.Bulk.

29. 
PROPERTIES –PROPERTIES –

Highly Highly DuctileDuctile, as they must adapt easily and, as they must adapt easily and
stick onto the refractory cast.stick onto the refractory cast.

Must Must VaporizeVaporize during burnout. during burnout.

30. BASEPLATE WAXBASEPLATE WAX
oror
MODELING WAXMODELING WAX
Supplied as,
Sheets of pink or red colour.

31. 
USES –USES –

To make Occlusion rim.To make Occlusion rim.

To form the desired contour of denture after To form the desired contour of denture after
teeth are set.teeth are set.

To make patterns for Orthodontic appliances.To make patterns for Orthodontic appliances.

32. 
CLASSIFICATION –CLASSIFICATION –
Type I = Soft ; for building Veneers.Type I = Soft ; for building Veneers.

Type II = MediumType II = Medium
Type III = HardType III = Hard

33. 
COMPOSITION –COMPOSITION –
Paraffin wax or Ceresin = 80 %Paraffin wax or Ceresin = 80 %
Beeswax = 12 %Beeswax = 12 %
Carnauba wax = 2.5 %Carnauba wax = 2.5 %
Natural or Synthetic resin = 3 %Natural or Synthetic resin = 3 %
Microcrystalline = 2.5 %Microcrystalline = 2.5 %

34. PROCESSING WAXPROCESSING WAX
**** Used mainly as accessory aids. Used mainly as accessory aids.

35. 
Examples are ,Examples are ,

Boxing Wax & Beading Wax.Boxing Wax & Beading Wax.

Utility Wax.Utility Wax.

Sticky Wax.Sticky Wax.

36. BOXING & BEADING WAXBOXING & BEADING WAX
USES --USES --
To build up vertical walls around the impression.To build up vertical walls around the impression.
SUPPLIED AS –SUPPLIED AS –
Boxing wax Boxing wax as sheets.as sheets.
Beading waxBeading wax as strips. as strips.

37. UTILITY WAXUTILITY WAX

Supplied as – Supplied as – Sticks and Sheets.Sticks and Sheets.

Uses –Uses – To adjust the contour of perforated tray. To adjust the contour of perforated tray.

Composition – Composition – Petrolatum & other waxes.Petrolatum & other waxes.

**** It is adhesive and can stick to the tray.It is adhesive and can stick to the tray.

38. STICKY WAXSTICKY WAX
USES --USES --

To join metal parts before soldering.To join metal parts before soldering.

To join fragments of broken dentures before To join fragments of broken dentures before
repair.repair.

39. COMPOSITION --COMPOSITION --
Mainly Yellow Beeswax, Rosin & Natural resins Mainly Yellow Beeswax, Rosin & Natural resins
such as Gum dammer. such as Gum dammer.
PROPERTIES –PROPERTIES –

Sticky when melted & Adheres closely to surface.Sticky when melted & Adheres closely to surface.

Firm and Brittle at room temperature.Firm and Brittle at room temperature.

40. IMPRESSION WAXESIMPRESSION WAXES

Used to record non – undercut edentulous Used to record non – undercut edentulous
portions of the mouth.portions of the mouth.

Examples are ,Examples are ,
** CORRECTIVE IMPRESSION WAX** CORRECTIVE IMPRESSION WAX
** BITE REGISTRATION WAX** BITE REGISTRATION WAX

41. CORRECTIVE IMPRESSION WAXCORRECTIVE IMPRESSION WAX

USES --USES --

To make functional impression of RPD.To make functional impression of RPD.

To record Posterior Palatal Seal.To record Posterior Palatal Seal.

Functional Impression for Obturatures.Functional Impression for Obturatures.

42. COMPOSITION --COMPOSITION --
• Paraffin waxParaffin wax
• Ceresin waxCeresin wax
• BeeswaxBeeswax
May contain metal particles.May contain metal particles.
PROPERTIES –PROPERTIES –
• FLOW at 37 FLOW at 37
0 0
C is 100 %.C is 100 %.
• Should be poured immediately.Should be poured immediately.

43. BITE REGISTRATION WAXBITE REGISTRATION WAX
USES --USES --
To record the relationship between the upper andTo record the relationship between the upper and
lower teeth.lower teeth.
SUPPLIED AS --SUPPLIED AS -- U shaped rods. U shaped rods.
COMPOSITION -- COMPOSITION -- Beeswax, Paraffin, Ceresin.Beeswax, Paraffin, Ceresin.

44. MCQsMCQs

1. The role of gum dammar in Inlay casting wax is:1. The role of gum dammar in Inlay casting wax is:
a) To improve cracking resistancea) To improve cracking resistance
b) To provide strength to waxb) To provide strength to wax
c) To impact smoothness to patternc) To impact smoothness to pattern
d) All of the aboved) All of the above

45. 
2. Carnauba was is preffered to candelila wax as:2. Carnauba was is preffered to candelila wax as:
a)a)It is harder and has less flowIt is harder and has less flow
b)b)It has low melting temperatureIt has low melting temperature
c)c)It provides luster to the patternIt provides luster to the pattern
d)d)All of the aboveAll of the above

46. 
3. Inlay wax should have following requisites:3. Inlay wax should have following requisites:
a)a)Its colour should be in contrast with tooth or die Its colour should be in contrast with tooth or die
materialmaterial
b)b)It should have capability to be carved according It should have capability to be carved according
to tooth anatomy and there should be no flaking.to tooth anatomy and there should be no flaking.
c)c)When heated, it should be completely eliminated When heated, it should be completely eliminated
from the mould.from the mould.
d)d)All of the above.All of the above.

47. 
4. Which of the following waxes is used for 4. Which of the following waxes is used for
making of casting pattern:making of casting pattern:
a)a)Boxing waxBoxing wax
b)b)Inlay waxInlay wax
c)c)Modeling waxModeling wax
d)d)Utility waxUtility wax

48. 
5. The minimum flow of inlay wax at 455. The minimum flow of inlay wax at 45
00
C C
should be:should be:
a)a)60%60%
b)b)6%6%
c)c)70%70%
d)d)100%100%

49. 
6. Which of the following correctly describe type 6. Which of the following correctly describe type
I inlay casting wax:I inlay casting wax:
a)a)Soft wax used for direct techniqueSoft wax used for direct technique
b)b)Medium wax used for indirect techniqueMedium wax used for indirect technique
c)c)Soft wax used for indirect techniqueSoft wax used for indirect technique
d)d)Medium was used for direct techniqueMedium was used for direct technique

50. 
7. The maximum ingredient of inlay casting wax:7. The maximum ingredient of inlay casting wax:
a)a)Paraffin waxParaffin wax
b)b)CeresinCeresin
c)c)Carnauba waxCarnauba wax
d)d)Gum dammarGum dammar

51. 
8. Which of the following is added inlay casting 8. Which of the following is added inlay casting
was to improve the smoothness:was to improve the smoothness:
a)a)CeresinCeresin
b)b)Candellila waxCandellila wax
c)c)Gum dammarGum dammar
d)d)Synthetic waxSynthetic wax

52. 
9. Percentage of Carnauba wax in inlay casting 9. Percentage of Carnauba wax in inlay casting
wax is:wax is:
a)a)40%40%
b)b)60%60%
c)c)25%25%
d)d)10%10%

53. 
10. Inlay casting wax is supplied as:10. Inlay casting wax is supplied as:
a)a)Sheets onlySheets only
b)b)Mesh form onlyMesh form only
c)c)Both of the aboveBoth of the above
d)d)None of the aboveNone of the above