Dental waxes are composed of natural and synthetic components that contribute different properties depending on temperature. They are classified as pattern, processing, or impression waxes depending on their intended use. Pattern waxes like inlay, casting, and baseplate waxes are used to construct dental restorations. Processing waxes aid clinical and laboratory procedures. Impression waxes are used to take impressions. Proper manipulation and control of temperature is important when working with waxes. The lost wax technique uses a wax pattern, investment, and casting process to produce dental restorations.

1. Composition and Properties
of Dental Waxes
CHAPTER 16

2. Dental Waxes
 Composed of a mixture of components from natural and synthetic
sources
 Natural waxes are produced from palnts, used in carnauba wax; insects, used
in beeswax; and minerals, used in paraffin and ceresin wax
 Contribute properties to the wax, but are rarely used in their pure form
 They are combined or mixed with synthetic waxes, gums, fats, oilts, resins
and coloring agents.

3. Dental Waxes
 Components of the waxes allow them to be
 Sticky
 Solid
 Liquid
 Depending on the temperature

4. Important Properties of Waxes
Melting range
Flow
Excess residue
Thermal expansion

5. Melting Range
Range of temperatures at which each component of the wax will
start to soften and then flow
Lower melting points will soften first; then, as the temperature is
increased, more components will soften and the wax will eventually
flow and become liquid or vaporize
Wax is unstable
Must be careful to prevent its distortion
Controlling temperature allows operator to control viscosity and flow
Flame source is needed if flowable state is desired
5

6. Flow
 Movement of wax as molecules slip over each other
 As the temperature increases, the viscosity decreases until the wax becomes liquid
 If a wax were capable of flow at room temperature, it would be very difficult to control
 If you’re using the wax for wax bite registration, you would not want it to flow at room
temperature, but you would also not want the melting range to be much higher than mouth
temperature.
 If you’re using wax in the lab to box an impression, it is much more desirable to mold the wax,
using the heat of your hands or warm water, rather than a flame
 Different waxes have different properties and uses.

7. Excess residue
 It is important that all wax be removed from
the object onto which its melted
If excess residue remains after the wax is
removed, this may result in inaccuracies in the
object being produced.

8. Thermal expansion
 Waxes expand when heated and contract when cooled
 Thermal expansion and contraction of waxes is greater than that of any other
dental material
 Especially important for pattern waxes
 If wax is heated too far above the melting range or is heated unevenly, expansion
above the acceptable standards will result
 If waxes are allowed to stand, dimensional changes occur from the release of
residual stress
 Wax patterns should be invested within minutes of carving

9. Classification of Waxes
Three classifications:
Pattern waxes
Processing waxes
Impression waxes
Manufacturers produce these waxes in several forms:
Sticks, sheets, blocks, and tins are used
9

10. Pattern Waxes
Used in the contruction of metal
castings and bases for dentures
Three types of PATTERN WAXES
Inlay wax
Casting wax
Baseplate wax
10

11. Pattern Wax- Inlay
 Inlay waxes are used to prepare patterns
for metal casting through the lost wax
technique.
 They may be used directly in the mouth
(type I), placed onto the prepared tooth
in the direct waxing technique, or, more
frequently, melted onto a die outside
the mouth in the indirect technique
(type II).

12. Pattern Wax-Casting
 Casting waxes are used to construct
the metal framework of partial and
complete dentures.
 These waxes come in sheets and
preformed shapes.
 The physical properties of casting
waxes are similar to those of inlay
waxes, with the exception of melting
range.

13. Pattern Wax--Baseplate
 Baseplate wax is used mainly to make
occlusion rims and to hold artificial
teeth to baseplates during the
fabrication of dentures.
 Baseplate wax is composed mainly of
beeswax, paraffin, and coloring
matter, which are mixed together,
cast into blocks, and rolled into
sheets.

14. Processing Waxes
 Used primarily to aid in dental procedures both clinically and in the
laboratory
 Three Types of Processing waxes
 Boxing wax
 Used to form a box around impressions of the mouth when a cast is made
 Utility wax
 Comes in long ropes that are easily manipulated at room temperature
 May be used with boxing wax to aid in the pouring of an impression
 Sticky wax
 Comes in orange sticks that at room temperature are hard and brittle, but when heated
under flame become soft and sticky
14

15. Processing Wax- Boxing
 The boxing wax limits the flow of the
stone/gypsum material.
 Boxing wax usually is issued in red strips
measuring 1½ inches wide, 12 inches
long, and 1/8 inch thick.
 Boxing wax is soft and pliable enough at
room temperature to be formed into a
desired shape without heating.

16. Processing Wax-Utility
 Utility wax is used to provide rim locks and otherwise to
adapt impression trays for individual impressions, to
build up post-dam areas on impressions, and to form a
bead or border on preliminary and final impressions.
 Can also be used to block out undercuts around teeth
or tissues prior to impression making, to prevent the
impression from locking in place
 AKA periphery wax
 Utility wax is pliable enough at room temperature to be
used without heating.
 Utility wax normally is issued in long ropes and usually
is red.
 Clear utility wax is used to cover orthodontic brackets

17. Sticky wax- processing
 Sticky wax has the property of
adhering components of metal,
gypsum or resin together
temporarily during fabrication or
repair
 Hard and brittle at room
temperature
 Heated under flame to become soft
 It is composed of beeswax, paraffin,
and resins.

18. Impression Wax
 Thermoplastic materials used to
obtain impressions of the oral
structures
 When heated, they become soft
 Able to take on a new form in the
mouth
 When cooled, they harden and
can be removed

19. Impression wax
 Corrective impression wax
 used in conjunction with other impression materials in the process of taking edentulous
impressions.
 This wax flows at mouth temperatures and is used to correct undercuts, to fill small voids, or to
help develop a functional posterior palatal seal for complete dentures
 Bite registration wax
 used to produce wax bite registrations for articulation of models.
 The preformed horseshoe shapes often are reinforced with metal particles to provide stability.
 Susceptible to distortion at temperatures only slightly higher than the mouth and must be
carefully monitored
19

20. Manipulation of Waxes
 Softening of wax should be done:
 Evenly in dry heat
 With warm hands
 With a warm water bath
 By flame
Rotated above so that it evenly softens or flows
 Melted wax should be added in layers
 Store waxes at or slightly below room temperature to avoid
distortion
20

21. Lost Wax Technique
 Primary steps to the lost wax and casting procedure are as follows:
1. Pouring the die
1. An exact impression of the prep is first obtained and poured into a high-strength die stone forming the
die
2. Waxing the die
1. A detailed wax pattern of the restoration is carved on the die including all anatomy, contours,
occlusion, and proximal contacts
3. Spruing the die
1. A wax or plastic sprue is attached to the pattern to form the channel into which the molten metal will
be forced
4. Attaching the sprue base
1. The sprue is attached to the sprue base; this forms the funnel to help guide the flow of molten metal
into the wax pattern.
21

22. Lost Wax Technique
5. Investing the wax pattern
5. The pattern and attached sprue are encased in an investment ring into which gypsum-based
investment is poured
6. Burning out the wax
1. Once hardened, the sprue base is removed and the investment-enclosed pattern and sprue are
heated in a burnout oven at high temperatures (500-700ºC), causing the wax and the sprue to
vaporize (lost wax), leaving an impression of the wax pattern in the now-empty space
7. Casting the restoration
1. The molten metal is moved by centrifugal force through the empty channel formed by the sprue
and into the empty wax patter space
8. Final steps
1. The metal cools, the sprue is removed, and the casting is cleaned and polished

23. Lost Wax Technique
 Artisans have used the lost wax technique for several hundred
years.
 In the 1500s, artisans, in conjunction with medical practitioners,
invented a method for casting gold for dental restorations in
molds; today’s techniques are much the same.
 https://youtu.be/LinG4dZilxw