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1. NATURAL WAXES:
Classified according to origin as:
a) Mineral- paraffin, microcrystalline, barnsdahl, ozokerite, cerecin, montan.
b) Plant- carnauba, ouricury, candellila, japan wax, cocoa butter
c) Insect- beeswax
d) Animal- spermaceti
Classified according to chemical composition as:
a) Waxes containing hydrocarbons
b) Waxes containing esters
c) Waxes containing free alcohol
d) Waxes containing acids.
 Chief constituents of mineral waxes- hydrocarbons(17-44 C atoms)
 Hydrocarbons in plant waxes- saturated alkanes(19-31 C atoms in odd no)
(these molecules having a range of molecular weight affect melting and flow property
of waxes)
 Plant and animal waxes contain esters as well in high concentration.
E.g. carnauba(plant wax) contains 85%alkyl esters of various kinds
Beeswax contains myricyl palmitate as the principal ester.
 Thus, natural waxes are complex combinations of organic compounds of high mol wt.
 The composition of these waxes varies, depending on the source and time of
collection. Hence manufacturers blend particular batches of waxes to obtain the
properties desired for particular application
Paraffin waxes:
 Obtained principally from high boiling point fractions of petroleum.
 Melting temperatures generally increase with inc. In molecular weight.
 Oils lower the melting temperature of the wax.
 Paraffin waxes used in dentistry are refined waxes and contain less than 0.5% oils.
 They crystallize in the form of plates, needles and malcrystals(uaually plates)
 Undergo cryatalline changes of transition from needles to plates on cooling(5-8°
below their melting temperatures)
 Volumetric contraction of 11%-15% is seen on cooling. Since the waxis a mixture
of hycrocarbons, yhis contraction is not uniform throughout the temperature range
from melting temperature to room temperature
Microcrystalline waxes:
 Similar to paraffin but obtained from heavier oil fractions, and as a result,
have higher melting points.

2.  Cryatallize in small plates and are tougher and more flexible than paraffin
waxes
 Have an affinity for oils and their hardness and tackiness can be altered by
adding oils
 Show less volumetric changes than paraffin during solidification
Barnsdahl:
 Type of microcrystalline wax.
 Used to increase melting range and hardness and reduce the flow of paraffin
wax.
Ozokerite:
 Earth wax found near petroleum deposits in central Europe and Western U.S.
 Similar to microcrystalline wax in having straight and branched chain
hydrocarbons but also contains some closed chain hydrocarbons.
 Has high affinity for oils.
 In conc. of 5%-15%, improves the physical characteristics of paraffins in the
melting range of 540C
Cerecin:
 Them used to describe waxes from wax bearing distillates from natural- mineral
petroleum refining or lignite refining.
 Are straight and branched chain paraffins.
 Have higher mol. Wt and hardness than waxes distilled from crude products.
 Used to inc. Melting range of paraffin waxes.
Montan wax:
 Obtained by extraction from various lignites.
 Although, they are mineral waxes, properties and composition are similar to
plant waxes.
 Hard brittle and lustrous.
 Blend well with other waxes, therefore, are often substituted for plant waxes to
improve the hardness and melting range of paraffin wax.
Carnauba and Ouricury:
 Composed of straight chain esters, alcohols, acids and hydrocarbons
 Characterized by high hardness, brittleness and high melting temperatures.
 Possess outstanding quality of increasing melting range and hardness of paraffin
waxes. E.g adding 10% carnauba to paraffin with melting range 200C increases
melting range to 460C

3.  Ouricury waxes are less effective than carnauba waxes, although have same
effect.
Candellila wax:
 Consist of 40-60% paraffin hydrocarbons containing 29-33 C atoms along with
free alcohols, acids esters and lactones.
 Like carnauba ouricury, they harden paraffin waxes but are not so effective for
increasing melting range.
Japan wax:
 Not a true wax, chiefly fats
 Contains glycerides of palmitic and stearic acid and high mol. Wt acids
 Tough, malleable and sticky material that melts at about 570C
 May be mixed with paraffin to improve tackiness and emulsifying ability
Cocoa butter:
 Not a true wax, chiefly fats
 Completely fat composed of glycerides of stearic, palmitic, oleic, lauric and lower
fatty acids.
 Brittle substance at room temperatures
 Used to protect against dehydration of soft tissues and to protect glass ionomer
products temporarily from moisture during setting or from dehydration after they
are set.
Beeswax:
 Primary insect wax used in dentistry.
 Complex mixtures of esters plus saturated and unsaturated hydrocarbons and high
mol wt. Organic acids.
 Brittle at room temp.
 Plastic at body temperature.
 Used to modify properties of paraffin waxes.
 Main component of sticky wax.
Spermaciti wax:
 Obtained from sperm whale and are mainly ester waxes
 Not used extensively in dentistry.
 Used as a coating in dental wax.
SYNTHETIC WAXES:
 Become available in the recent years.

4.  Still limited in dental formulations. Natural waxes continue to be the primary
components.
 Are complex organic compounds of various chemical composition.
 Differ from natural waxes in certain characteristics because of their high degree of
refinement, in contrast with the contamination that is common in natural waxes.
 Synthetic waxes include:
a) Ployethylene wax(mol wt = 2000-4000; melt at 100-1050C)
b) Polyoxyethylene hydrocarbon wax(37-630C)
c) Hydrogenated wax
d) Halogenated hydrocarbon wax
e) Wax esters from reaction of fatty acids and alcohols.
 Polyoxythylene waxes have limited compatibility with other waxes but do function as
plasticizers and tend to toughen films of wax
 Other synthetic waxes are produced by reactions with natural waxes or wax products
E.g chloride in preparation of halogenated waxes and hydrogen in preparation of
hydrogenated waxes.
GUMS:
 Many waxes obtained from plants and animals resemble in appearance a group of
substances described as gums.
 Gums are viscous amorphous exudated which harden on exposure to air.
 These are complicated substances, mainly carbohydrates
 When dissolved in water, they either dissolve or form sticky viscous liquids.
FATS:
 Although waxes are harder and have higher melting temperatures than fats, but in
some ways they resemble waxes:
 Both are colourless, tasteless o odourless in the pure form and usually feel
greasy.
 Chemically, fats are composed of esters of various fatty acids with glycerol
and are known as glycerides, which distinguishes them from waxes. Examples
are glycerides of stearic acids found in beef tallow. It may be used to increase
melting range and hardness of compounded wax.
 Hydrocarbon oils may be used to soften mixtures of waxes.
 Silicone oils may be used o improve ease of polishing with waxes.
RESINS:
 Although they form a distinct class of substances, in some respects, natural resins
resemble waxes in appearance and properties.
 Natural resins are exudates obtained from trees and plants E.g dammar, rosin,
sandarac. Shellac is produced by plants.

5.  Natural resins are insoluble in water but show varying solubility in certain organic
liquids.
 Numerous resins are mixed with waxes to develop waxes for dental applications
 Dammar and kauri are added to waxes to produce harder products
 Polyethylene and vinyl may be added to paraffin wax to improve their
toughness, filming characteristics and melting ranges.
 Used in organic solvents to produce film forming materials that may be used
as cavity liner E.g copal and polystyrene.
PROPERTIES OF WAXES:
Melting range:
 Because waxes contain several types of molecules having a range of molecular
weights, they have melting ranges rather than melting points.
Thermal expansion:
 Waxes expand when subjected to a rise in temp. and contract as the temp. Is
decreased.
 This property may be slightly altered when various waxes are blended.
 Dental waxes and their components have the largest coeff of thermal
expansion of any material used in restorative dentistry.
 The linear thermal expansion properties of waxes may be explained on basis
of strength of secondary valence force and transition points.
 Mineral waxes have a higher coeff of thermal expansion than plant waxes.
This is because they have weak secondary valence forces, which are easily
overcome by energy absorbed during rise in temperature. This permits more
movement of the wax components, thus allowing a greater amount of thermal
expansion.
 On the other hand, plant waxes have high secondary valence forces because of
their high conc. of esters. Because the secondary valence forces restrict
movement of wax components, small coeff of thermal expansion are observed
until the melting range of the wax is approached.
 Many waxes exhibit atleast two rates of expansion between 220Cvand 520C.
These changes in rates of expansion occur at transition points. At these points,
the internal structural components become free to move.
 Because the ingredient waxes are undergoing transitions that do not coincide
with one another, certain inlay waxes exhibit more than two changes in the
rate of expansion.
 Because the coeff. Of expansion of inlay wax is so great, temperature changes
in wax patterns after the critical dimensional relationships are set maybe ?????

6. MECHANICAL PROPERTIES:
 The elastic modulus, proportional limit and compressive strength of waxes are low
compared with those of other materials. These properties depend strongly on
temperature.
 Carnauba wax has the highest elastic modulus and beeswax has the lowest.
 The modulus of inlay wax is important in the hygroscopic expansion of casting
investments, in which the wax pattern is subjected to stresses resulting from
expansion of investment during setting.
 Non uniform deformation of wax patterns, such as crowns, can be minimized by using
waxes having different elastic moduli for particular parts of the pattern. E.g in a
crown, lateral walls can be prepared with inlay wax and occlusal surface can be
constructed of soft green casting wax. The modulus ratio of inlay and casting wax at
investing temperature is 7:1 which is the approximate ratio needed for many patterns
to obtain uniform expansion in occlusal and marginal areas.
 The proportional limits and compressive strengths of waxes exhibit the same trend as
their elastic moduli.
Flow:
 The property of flow results from slippage of molecules over each other.
 A measure of flow in the liquid state of wax would be synonymous with viscosity.
However, below the melting point of wax, the measure of flow would be the measure
of plastic deformation of the material at a given temperature.
 Flow is dependent upon: the temperature of the wax, force bringing about the
deformation, and the time for which force is applied.
 Flow increases as the melting point of the wax is reached.
 Although a high flow for a specific wax may be required at a given temperature, it
may be extremely deleterious at a temperature few degrees lower. This is especially
true for inlay wax( it should have a high flow a few degrees above mouth temperature
so that it is workable but not uncomfortably warm when placed in the patient’s
mouth. However, at mouth temperature, an inlay wax to be used for a direct pattern
must have essentially no flow to minimize the possibility of distortion of the pattern
during removal from tooth cavity.)
 Most mineral waxes have a 100C range between1% and 70% flow, which indicates
that these waxes soften gradually over a broad temperature range.
Residual stresses:
 Regardless of the method used to prepare a wax pattern, residual stresses exist in
the pattern.
 The presence of residual stresses can be demonstrated by comparing the thermal
expansion curves of annealed wax with wax that has been cooled under
compression or tension.

7.  When wax specimen is prepared by holding the softened wax under compression
during cooling, followed by the determination of thermal expansion, the thermal
expansion is greater than for annealed specimen.
 The extent of deviation from the curve for annealed wax is a function of the
magnitude of the residual internal stresses and the time and temperature of storage
of wax specimen before thermal expansion curve id=s determined.
 When the wax specimen is cooled while being subjected to tensile stresses, and the
thermal expansion is determined, the curve for the wax specimen is lower than that
for annealed specimen..
 If sufficient residual stress is introduced, a thermal contraction may result on
heating.
 These changes in the dimensions of wax patterns on heating them under
compression or tension can be explained as follows:
 When the specimen is held under compression, during cooling, the atoms
and molecules are forced close together than when they are under no
external atresses.
 After the specimen is cooled to room temperature, and the load is removed,
the motion of the molecules is restricted. This restriction results in residual
stresses in the specimen. When the specimen is heated, release of stresses is
added to the normal thermal expansion, and the total expansion is greater
than normal.
 When the specimen is cooled while under tensile stress, and expansion as
result of heating is measured, the release of the residual tensile stress results
in dimensional change that is opposite to the thermal expansion. The sum of
both these effects result in a lower expansion than for annealed wax.
Ductility:
 Like flow, ductility increases as the temperature of the wax specimen is increased.
 Waxes with lower melting temperatures have a greater ductility at any given
temperature than those with hogher temperature.
 The ductility of blended wax is greatly influenced by distribution of the melting
temperature of the component waxes.
 A blended wax with components having wide melting ranges generally has greater
ductility than blended waxes that have a narrow range.
 On heating, the softening point of the lowest component is reached first. A further
temperature rise begins to liquefy this component and approach still closer to the
softening points of the higher softening point components. This tends to plasticizt
the entire wax mass thereby enhancing ductility.
 Generally highly refined waxes are brittle.

8. DENTALWAXES:
Classification:
I Pattern wax
a) inlay wax
b) casting wax(sheets, ready shapes, waxups)
c) base plate wax
II Processing wax
a) boxing wax
b) utility wax
c) sticky wax
III Impression wax
a) corrective wax
b) bite registration wax.
 Pattern waxes are used to form the general predetermined size and contour of an
artificial dental restoration, which is to be constructed of a more durable material such
as cast gold alloys, Co-Cr-Nialloys or acrylic resins.
 All pattern waxes have two major qualities- thermal change in dimension and
tendency to warp or distort on standing, which creates serious problems whether inlay
pattern, crown or complete denture is being constructed.
 Processing waxes are used primarily as auxillary aids in constructing a variety
restorations and appliances, either clinically or in the laboratory.they help to simplify
dental procedures of denture construction and soldering.
Inlay pattern wax:
 the first procedure in the casting of an inlay or a crown for the lost wax process is the
preparation of a wax pattern.
 The cavity is prepared in the tooth and the pattern carved, either directly in the tooth
or on a die that is a reproduction of the tooth and prepared cavity. If the pqttern is
made within the tooth, it is said to be prepared with direct technique.
 The ANSI/ ADA specification no4 covers two types of inlay waxes:
Type I( medium wax) employed in direct technique
Type II(soft wax ) employed in the indirect technique.
 The pattern should be an accurate reproduction of the missing tooth structure. The
wax pattern forms the outline of the mould into which the alloy is cast.
 Consequently, the casting depende on the accuracy of the pattern.

9.  Before adaptationof wax pattern to the tooth or die, a separating medium must be used
to ensure the complete separation the wax pattern without distortion.
Composition:
 The essential ingredients are paraffin, microcrystalline wax, cerecin, carnauba,
candellila and beeswax. E.g inlay wax may contain 60% paraffin, 25% carnauba,
10% cerecin, and 5% beeswax.
 Some inlay waxes are described as hard medium or soft. This is a general indication
of their flow.
 Paraffin, which is derived from high boiling fractions of petroleum, can be obtained
in wide melting or softening range, depending on the mol.wt and distribution of
constituents. Thus, paraffin used for type I wax is has a higher melting point than
paraffin used for type II waxes
 One disadvantage of paraffin is that it is likely to flake when trimmed and does not
present a smooth glossy surface. Consequently, other waxes and resins are added as
modifying agents.
 In modern inlay waxes, carnauba wax is often replaced in part, with certain synthetic
waxes that are compatible with inlay wax. Atleast 2 waxes of this type can be used:
a) One is complex nitrogen derivative of the higher fatty acids
b) Other is composed of esters of acids derived from montan wax.
 Control of properties of wax is accomplished by a combination of factors including
amount of carnauba wax, melting range of hydrocarbon wax and the presence of
resins.
Desirable properties:
1. When softened, thw wax should be uniform. It should be compounded with
ingredients that blend well with each other so that there is no graininess or hard spot
when the wax is softened.
2. The colour should be such that it contrasts with the die material or prepared tooth. It is
necessary to carve the wax margins close to the die, therefore, a definite contrast in
colour facilitates proper finishing of margins.
3. There should be no flakiness or similar surface roughening when wax is bent or
moulded after softening.
4. The wax pattern should allow being carved to a thin layer because after the wax
pattern solidifies, it is necessary to carve the wax at margins so that the pattern
confirms exactly to the surface of the die.
5. The wax should completely burn out leaving no residue as the residue may orovidean
impervious coating on the walls of the mould which might adversely affect the final
cast inlay. ADA sp. No 4 requires that the melted wax, when it is vapourized, at 500
0C shall leave no solid residue in excess of 0.10% of the original weight of the
specimen.
6. Ideally, the wax pattern should be completely rigid and dimensionally stable at all
times until it is eliminated.

10. Flow:
 Inlay wax should exhibit a marked plasticity or flow at temperatureslightly above that
of the mouth.
 Inlay waxes do not solidify with a space lattice, as does a metal. Instead, the structure
is more likely to be a combination of crystalline and amorphous materials, displaying
limited ordering of molecules.
 The wax lacks rigidity and flows even at room temperature.
 Flow is measured by subjecting cylindrical specimens to a designated load at a stated
temperature and measuring % of elongation in length.
 Max. Flow permitted for type I wax at 37 0C is 1%. The flow at this temperature
permits carving and removal of the pattern from prepared cavity at oral temperatures
without distortion.
 Since the wax pattern (both typeI and type II)is inserted into the cavity at
approx.450C, they should have minimum 70% and maximum 90% flow at this
temperature to have sufficient plasticity and flow in all areas in the preparation to
reproduce the required details.
Mechanical properties:
 The thermal conductivity of waxes is low and time is required both, to heat them
uniformly throughout and to cool them to body/ room temperature.
 Characteristic property of inlay wax is high coeff of thermal expansion.
 Compared with thermal expansion of other dental materials, inlay wax expands and
contracts thermally more per degree temperature change than any other dental
material.
 This is one disadvantage inherent in waxes when they are used in direct technique.
This property is less significant when the waxes are used in indirect technique
because the pattern is not subjected to a change from mouth to room temperature.
Hence, ADA specification no 4 contains no requirements for thermal expansion of
typeII waxes. A max of 0.6% linear shrinkage in dimension is permitted for type I
wax.
 The amount of thermal dimensional change may be affected by the previous
treatment of the wax. E.g if the wax is not cooled under pressure, transition
temperature is not so pronounced when reheated.
 Glass transition temperature: temp. At which a change in rate of expansion occurs.
This is because some constituents of the wax probably change crystalline form at this
temperature, and the wax is more plastic at higher temperatures.
 However, there is another explanation for the difference in behaviour on reheating, of
the wax cooled under pressure and the same wax cooled without applying pressure. It
is related to behaviour of dissolved air or solvents. Certain waxes have a phenomenal
capacity for gas and solvent retention, which may remain undetected. The gas
expands on reheating causing pronounced expansion of the pattern.

11. Wax distortion:
 Most serious problem encountered when the pattern is removed from mouth
or die
 Results from thermal changes and release of stresses which result from
contraction on cooling, occluded air,, change of shape during moulding,
carving removal and time and temperature during storage
 Waxes tend to return to their original shape after manipulation- elastic
memory.
 This is more critical in inlay waxes than other impression materials, because
resulting metallic restorations must fit onto hard unyielding hard tooth tissue.
Manipulation of inlay wax:
 Dry heat is gen preferred to the use of a water bath,as the water can result in the
inclusion of droplets of water that could splatter on flaming, smear wax surface on
polishing and distort the pattern on thermal changes.
 Direct pattern technique:
 stick is softened over a flame. Take care not to overheat it.
 It shd be twirled until it becomes shiny and then removed from the flame.
 Repeat the process until the wax is warm throughout
 Wax is then kneaded and shaped to the prepared cavity.
 Type I wax has adequate plasticity in the temp range safely tolerated by the
pulp.
 Pressure is applied by the finger or by the patient biting on the wax.
 Gradually cool at mouth temperature, not by cold water.
 While removing, the pattern shd be hooked with an explorer and rotated out
of the cavity
 An MOD pattern can be removed by luting a staple so that each prong is
fastened above a corresponding step portion.
 Can be removed with a dental floss looped thru a staple amd withdrawn in
direction parallel to the axial walls.
 After removing, avoid touching with fingers as much as possible to prevent
any temperature changes.
 Indirect pattern technique:
 First lubricate the die, preferably with a lubricant containing a wetting
agent.
 Molten wax is added in layers with a spatula or a waxing instrument,
or painted on with a brush.
 Prepared cavity is overfilled and wax is then carved to the proper
contour.
 While carving the margins, extreme care shd be taken to avoid
abrading any surface of stone die.
 Silk cloth may be used for polishing of the pattern, rubbing towards
the margins.

12.  Another excellent method is to swage the pattern
 Die and pattern are mounted in closed vessel with a piston and
containing water at 380C
 When pressure is applied to the piston, a hydrostatic pressure is
applied entirely over the finished pattern. This minimizes final
distortion.
CASTING WAX:
 Used to fabricate the pattern for metallic framework of RPD and other similar
structures
 Available in the form of sheets, (28-38guage),ready made shapes and in bulk.
 The ready made shapes are supplied as round, half round and half pear shape.
 Exact composition not known. Similar to inlay wax, with various combinations and
proportions of paraffin , cerecin, beeswax, resins, and other waxes.
 Other uses are- post damming of complete denture impressions, checking high points
in the articulation, producing wax bites of cusp tips for articulation of stone casts etc.
BASE PLATE WAX:
 Derives its name from the baseplate tray to establish the vertical dimension, plane off
occlusion,and initial arch form in the technique for complete denture construction.
 Pink colour provides esthetic colour for initial stage of construction of the denture
before processing
 Patterns for orthodontic appliances and prosthesis other than CD are also made of
base plate wax
 Composition: may contain paraffin based waxes or commercial cerecin with small
quantities of other waxes, resins and additives to develop specific qualities.. a typical
composition may include: cerecin 80%, beeswax12%, carnauba 2.5%, natural or
synthetic resin 3%, microcrystalline or synthetic wax 2.5%.
 Practical requirements:
 Softened sheets shall cohere readily without becoming flaky or adhering to
fingers
 No irritation to oral tissues
 Trim easily with a sharp instrument at 23 degrees
 Soft glossy surface after gentle flaming
 No residue on porcelain/ plastic teeth
 Colouring shall not separate
 No adhesion to other sheets of wax during storage.
BOXING WAX:
 Used to form a wax box around the impression into which the freshly mixes plaster os
stone is poured.

13.  Requirements:
 Should be pliable at 21 degrees
 Should retain its shape at35 degrees
 Should easily adapt to impression at room temp. Without causing its distortion
 Should be slightly tacky and have sufficient strength
UTITITY WAX:
 Supplied in both stick and sheet form in dark red and orange colour.
 Have highest ductility and flow of all waxes.
 May be used to bring perforated tray to a desired contour
 May be used on the lingual portion of a bridge pontic to stabilize it while a labial
plaster splint is poured.
 Requirements:
 Should be easily workable, soft, pliable and adhesive
 Flow should not be less than 65% nor more than 80%
 Sufficient adhesiveness is required because building one layer on the other is
often desired.
STICKY WAX:
 Formulated from a mixture of resins or other additive ingredients.
 Such a material is sticky when melted and adheres closely to the surfaces on which it
is applied.
 This wax shd fracture rather than flow if it is deformed during soldering or repair
procedures.
 Specifications:
 Should have a dark or vivid colour so that it is readily distinguishable from
light coloured gypsum materials.
 Sticky when melted, adheres closely
 Not more than .2% residue on burnout
 Not more than 0.5% shrinkage from 43-28 degrees