2. Dental waxes
variety of natural waxes and resins have been used in
dentistry for specific and well defined applications.
Waxes are thermoplastic materials which are solids at
room temperature but melt without decomposition to form
mobile liquids.
They consist of two or more components which may be
3. THERMAL PROPERTIES OF
WAXESMELTING RANGE
• Waxes have a melting range rather than a
melting point.
• Example : paraffin 44 – 62 C⁰
carnauba 50 – 90 C⁰
• Significance: Mixing of waxes can change their
melting range.
COEFFICIENT OF THERMAL EXPANSION
• Waxes expand when there is increase in
temperature and contract when there is decrease
in temp.
• Dental waxes have the greatest co-efficient of
thermal expansion than any other restorative
materials in dentistry .
• Eg : CTE of type 1 wax is[ between 22C⁰ and
37.5C ⁰] is 323 10-6
FLOW
• Is the slippage of wax molecules over each
other.
• Measure of flow is the measure of the degree of
4. MECHANICAL PROPERTIES
Compressive strength , proportional
limit, elastic modulus of waxes are
low.
These properties strongly depends
on the temperature
As the temp decreases mechanical
properties improveCHEMICAL NATURE
Two principle groups of organic
compounds :
• Hydrocarbons : saturated alkanes Esters
• myricyl palmitate [bees wax]
Some waxes in addition contains free
alcohol and acids
7. Inlay wax
• Classification(ADA Sp. No. 4)
• It is a type of pattern wax.
Type I: Medium wax employed in
direct technique.
Type II: Soft wax used for indirect
technique for inlays and crowns.
• Uses of inlay wax:
1. It is used to make patterns for
metallic restorations.
2. Patterns for inlays,
3. crowns and bridges is first made in
wax and then converted into metal or
ceramic by casting.
8.
9. Casting wax
• It is a type of pattern wax.
• Classification (According to FDI Specification No. 140).
Class I : 28 gauge, pink ,Flow of about 10 % at 35C˚ Easily
adaptable at 40 to 45C˚
Class II :30 gauge, green ,Minimum flow of 60 % at 38C˚
,adapts well to the surface ,not brittle on cooling
Class III: readymade shapes, blue Will burnout at 500C˚ leaving
no carbon residue ,Supplied As Sheets 0.40 and 0.32 mm
thickness.
• Used to produce the metallic component of partial denture on
the cast.
Class I Class II Class III
10.
11. Base Plate Wax
• Classification (ADA Sp. No. 24)
• It is a type of pattern wax.
• Uses: used mainly in preparing wax patterns
for prosthesis.
• Supplied as : Sheets of pink or red color.
12. Wax rim (bite rim):
• It is a type of pattern wax.
• The softening temp. is above the mouth
temp.
• It is tough & resist fracture during removal
from the cast.
• It used for :
1. Restoring the occlusal relationship.
2. Arrangement of teeth.
3. Check the denture inside the patient
mouth.
Bite blockBite stick
13.
14.
15. Shellac denture base:
• It is a type of pattern wax
• Wax like resin stable at mouth temp.
• It has high softening temperature than
other waxes.
• It is used as a temporary denture
base.
16.
17. Sticky wax:
• It is a type of processing wax.
• It is sticky when melted, with a
max 5 %flow at 30 Cº and 90 %
at 43 Cº .
• It adheres closely to the surfaces
when applied to it.
• If movement occurs the wax
tends to fracture than distort.
• At room temperature the wax is
brittle and breaks easily
• Uses
1. It is used to align fractured parts
of acrylic dentures .
2. It is used to align fixed partial
denture units before soldering .
3. It is used to seal a plaster splint
to the stone cast during
18. Utility Wax
• It is a type of processing wax
.
• Supplied as : It is available in
the form of sticks and sheets.
Orange or dark red in color.
In orthodontics, periphery
wax is white in color
• Flow at 37.5Cº- min. 65 %
and max. 80% .
• Pliable and tacky at 21-24Cº
• Uses:
It can be used to alter the stock
tray extensions . The following
alterations :
1. can be made Height of the
tray .
19.
20. Boxing & beading waxes:
It is a type of processing wax.
Use:
• Beading wax is adapted around the impression borders to
create the land area of the cast
• Boxing wax is used to build up vertical walls around the
impression in order to pour the gypsum product to make a
cast base.
Supplied as :
• Boxing wax as sheets.
• beading wax as strips.
25. Impression waxes:
Corrective wax :
• Wax in combination with resins of low
melting point can be used in corrective
impression technique in partial and
complete denture prosthesis.
• The peculiarity of impression wax is that
they flow at mouth temperature.
• Availability : sheets or cakes
• Used to restore the selected region in the
edentulous patients to reproduce the details
of mucous membrane.
• Its main disatvantage is that it is distorted
26. Impression waxes
Bite registration wax :
It is used to record the relationship of the upper
& lower teeth in dentulous patients .
28. Analog Wax Heater :
Dental Lab Equipment is a high quality wax pot
and ideal for all dental applications. Its
temperature controlled heating system gives you a
broad temperature range of 70 F to 237 F (21 C
to 112 C). In addition, this wax pot features an
insulated thermoplastic housing which remains
cool while wax stays hot!