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WAXESDR. FEBEL HUDA, M.D.S,DICOI,FICOI,FAD,DLD.
ORAL MAXILLOFACIAL PROSTHODONTIST AND IMPLANTOLOGIST DIPLOMATE FROM THE INTERNATIONAL CONGRESS OF ORAL
IMPLANTOLOGY FELLOW FROM THE INTERNATIONAL CONGRESS OF ORAL
IMPLANTOLOGY DIPLOMATE IN LASER DENTISTRY (UNIVERSITY OF GENOVA -
ITALY) FELLOW IN AESTHETIC DENTISTRY (UNIVERSITY OF GREIFSWALD -
GERMANY)
HISTORY
3000 B.C
60 MILLION YEARS AGO INSECT WAX USED TO BE A DIET SOURCE
GREEK AND ROMAN
HISTORY• Matthaeus Gottfried Purmann in 1700 used
wax as models for prosthodontic purpose.• 1711 – Matthaeus Gottfried Purmann,first to
use bee wax as a impression material• The English term 'wax' is derived from the
Anglo-Saxon 'weax‘• 1935 - Fischer-Trop’s
CLASSIFICATIONS• ACCORDING TO THE ORGIN:
• NATURAL
• Minerals• Paraffin• Microcrystalline• Montan• Ceresin • Barnsdehl• Ozokerite•
• Plants • Carnuba• Ouricury• Candelilla• Japan wax• Cocoa butter• Insect• Beewax • Animal• Spermaceti
• SYNTHETIC WAXES
• Aerosol OT• Albacer• Acrawax • Durawax 1032• Castorwax• Flexo-wax C• Epolene N-10
• ACCORDING TO USE:
• Pattern waxes• Inlay casting• RPD casting• Base plate • Dipping wax• Margin wax• Sprue wax
• Processing waxes• Boxing wax• Modeling wax• Sticky wax• Occlusal rim wax• Spool wire wax • Impression waxes• Corrective• Bite registration
• ACCORDING TO ORGANIC COMPOUNDS:
• Hydrocarbons• Paraffin wax• Microcrystalline• Ozokerite• Carnauba • Ouricury• Candelilla• Beewax
• Esters • Beewaxes• Montan wax • Carnauba• Ouricury • Candelilla
• Alcohols • Montan wax• Carnauba • Ouricury • Candelilla
• Acids• Montan wax• Carnauba• Ouricury• Candelilla• Japan wax• Cocoa butter• Bees wax
PROPERTIES:
• Melting range• Thermal expansion• Mechanical properties• Flow• Residual stress• Ductility• Wettability
MELTING RANGE WAXES MELTING POINT in ˚C
Paraffin wax 40-71Microcrystalline 60-91
Barnsdahl 70-74Ozokerite 65Ceresin No valueMontan 72-92
Carnauba 84-91Ouricury 79-84Candelilla 68-75Japan wax 51
Cocoa butter No valueBeeswax 63-70
THERMAL EXPANSION
WAXMINERAL
WAX(weak
secondary Valence force)
PLANT WAX
Presence of
ESTHER
THERMAL EXPANSION
Carnauba Montan
Carnauba
Montan
22˚C AND 52˚C
THERMAL EXPANSION
18 28 38 48
MECHANICAL PROPERTIES
Temperature
Proportional limit(P)
Compressive strength Modulus of
elasticity (E)
MODULUS OF ELASTICITYWAXES E
(↓)TEMPERATURE
(↑)Carnauba wax 1790 to 760
MPa 23˚ to 37˚ C
Paraffin wax 310 to 28 MPa 23˚ and 30˚ C.
Inlay wax (75% paraffin
and 25% carnauba wax)
760 to 48 MPa 23˚ and 40˚ C
MODULUS OF ELASTICITY
PROPORTIONAL LIMIT (P)WAXES P
(↓)TEMPERATUR
E(↑)
carnauba wax 11 to 5.5 Mpa 23˚ to 37˚ C.
Inlay casting wax
4.8 to 0.2 MPa
23˚ to 40˚ C
COMPRESSIVE STRENGTH
x
83 to 0.5 MPa
23˚ to 40˚ C.INLAY WAX
HENCE INLAY WAX IS A BRITTLE MATERIAL
Flow
Time for which the force is
applied
Temp of waxFlow is greatly increased as melting point is approached
The force applied
FLOW
DIRECT INLAY WAX
NO FLOW AT ORAL
TEMP
↑FLOW ABOVE ORALTEMP
FLOW (Yellow Bee Wax)
HENCE USED IN IMPRESSION WAX
7% FLOW↑
40˚C
NO FLOW ↓ 38˚C
RESIDUAL STRESS
RESIDUAL STRESS
RESIDUAL STRESS CAN BE APPRECIATED ON THE EXPANTION CURVE
MAGNITU
DETIMETEM
PERATURE
EFFECT OF COMPRESSION ON RESIDUAL STRESS
COOLED UN
DER
COMPRESSION
ATOMS & MOLECULES ARE
FORCED TOGETHER
INCRESEDRESIDUAL STRESS,
INCREASING THE
EXPANSION
EFFECT OF TENSION ON RESIDUAL STRESS
COOLE
D UNDER
TENSION
ATOMS & MOLECULE
S MOVE AWAY IN OTHER
DIRECTION
ON HEATING,
RESUDIAL STRESS
RELEASED,
DECREASES EXPANSION
DUCTILITY
• It increases as the temperature of the wax is increased.
• Waxes with a lower melting temperatures have a greater ductility
WETTABILITY
• The wetting which occurs at the surface of the wax pattern during investing is generally poor.
NATURAL WAXES
MINERAL WAXES
PARAFIN WAXES
melting point – 52˚C weight ↓ at 157˚C till the contents vapours at
300˚C
26 – 30 carbonFRACTION
PARAFIN WAXES
OIL0.5%
PARAFFIN
↓ MELTING POING
75% CARNAUBA
↓ MELTING PIONT BY 1.5˚CFlow 28˚C – 31˚C
PARAFFIN WAXPARAFFINWAX
>0.5 103MN/m²11-15%5˚C – 8˚C
1gm - USED TO COLLECT SALIVA FOR SALIVA TEST
MICROCRYSTALLINE WAXES
SIMILLAR TO
PARAFIN WAX
MICROCRYSTALLINE WAXES
FROM HEAVIER OIL
FRACTION
MELTING POINT
MICROCRYSTALLINE WAXES
MICROCRYSTALLINE WAXES
OIL MICROCRYSTALLINE WAXES
OIL
HARDNESS AND
TACKINESSALTERED
VOLUMETRICCONTRACTION
TO PARAFIN WAXES
BAMSDAHL WAXES
1. BAMSDAHL WAXES IS A MICROCRYSTALLINE WAX
BAMSDAHL
MELTINGPOINTHARDNESSFLOWPARAFIN WAX
OZOKERITE WAXES
Ozokerite is similar to microcrystalline
wax
Earth wax
Central Europe Western United States
OIL OZOKERITE WAXES
IMPROVES PHYSICAL
PROPERTIES AT 54˚C
5% to15%
PARAFIN WAX
CERESINE WAXES
Natural-mineral petroleum refining Lignite refining
CERESINE WAXES
MELTINGPOINTPARAFIN WAX
MONTAN WAXES
Montan wax is also known as lignite wax or OP wax. Their composition and properties are similar to those of the
plant waxes. Found in Germany, and in the Ione Basin, California. It can be used for making car and shoe polishes, different
paints, and phonograph records, and also as lubricant for paper and plastics.
MONTAN WAXES
MELTINGPOINTHARDNESS
PARAFIN WAX
PLANT WAXES
CARNAUBA WAXES
Carnauba palm
Grows only in the northeastern Brazilian states
Also known as the queen of waxes
It is obtained from the leaf of the carnauba palm by gathering them, beating to loosen the wax, and then through refining and bleaching
Hard yellow-brown flakes
COMPOSITION
CARNAUBAWAX
STRIGHT CHAIN OF ESTERS
ALCOHOL ACID
HYDROCARBONS
HARDNESS
BRITTLENESS
MELTING RANGE
CARNAUBA WAXES
10%CARNAUBA
MELTINGPOINT
BY26˚C
TRANSITION TEMPFLOWPARAFIN WAX
246˚C - LOSS OF WEIGHT 485˚C – COMPLETE VAPOURS OF WAX
CARNAUBA WAXES
25%PARAFIN
WAX
MELTING TRANSITIONBY 5˚C – 6˚C
26%PARAFIN
WAX
NO EFFECTCARNAUBA WAX
OURICURY WAXES
• Has the same structures as carnauba wax
• Adding ouricury waxes produces a similar effect, but they are less effective than carnauba wax.
CANDELILLA WAXES
CANDELILLA WAXES
40% - 60% PARAFIN
HYDROCARBONLACTONES
WITH 29 – 33 CARBON
ALCOHOL ACID
ESTHER
LACTONES
CARNAUBA WAXES
CANDELILLA WAX
HARDNESSPARAFIN WAX
JAPAN WAX
• NOT A TRUE WAX - CHEIFLY FAT
JAPAN WAX
GLYCERIDES
PALMITIC STERICACID
HIGHER MOLECULAR WEIGHT ACID
JAPAN WAX
TOUGH
MALLEABLE
STICKY
JAPAN WAX
JAPAN WAX
EMULSIFYINGABILITYTACKINESSPARAFIN WAX
JAPAN WAXJAPAN WAX
COCOA BUTTER
• NOT A TRUE WAX - CHEIFLY FAT
COCOA BUTTER
GLYCERIDES&
STEARIC
PALMITIC
OLEIC
LAURIC
LOWER FATTY ACIDS
COCOA BUTTER
PREVENT DHYDRATION OF SOFT TISSUES
PROTECTS GIC FROM MOISTURE AND DEHYDRATION
INSECT WAXES
BEES WAX
SATURATED & UNSATURATED
HYDROCARBONS
HIGH MOLECULAR
WEIGHT ORGANIC
ACID
ESTERS
BEES WAX
• Beeswax is a natural wax created in the bee-hive of honey bees
• The wax of honeycomb is nearly all white, but becomes progressively brown or yellow by the introduction of pollen oils
BEES WAX
3mm
0.1 mm THICK
About 1200 are needed to make a single gram of wax.ITS BRITTLE AT ROOM TEMPERATUREBUT PLASTIC AT ORAL TEMPERATURE
BEES WAX
BEESWAX
20 – 500 ˚C34˚C AND 400˚C
ANIMAL WAXES
SPERMACETI WAXES
• SYNTHETIC WAXES
SYNTHETIC WAXES
SYNTHETIC WAXESPOLYETHYLENE WAXES (ml wt = 2000-4000,mp 100 – 105˚C)
POLYOXYETHYLENE GLYCOL WAXES (mp – 37 – 63˚C)
HALOGENATED HYDROCARBON WAXES
HYDROGENATED WAXES
WAX ESTERS FROM REACTION OF FATTY ALCOHOLS AND ACIDS
ACCORDING TO USE
PATTERN WAXES
INLAY WAXES
Inlay casting
DEEP BLUE, GREEN, PURPLE AND WHITE
INLAY CASTING WAXES
INLAY CASTING
WAX
PARAFFIN 60%
CARNAUBA 25%
CERESIN 10%
BEE WAX 5%
CANDELILLA &
MICROCRYSTALLINE
CLASSIFICATION
BY FLOW
HARD
REGULAR
SOFT
INLAY WAX (ADA-NO:4)
HARD
• LOW FLOW• WARM
WEATHER• LESS
SHRINKAGE
REGULAR
• MODERATE FLOW
• TYPE I• DIRECT
TECHINQUE
SOFT
• TYPE II• INDIRECT
TECHNIQUE• MORE
SHRINKAGE• WORKED AT
ROOM TEMPETATURE/COLD WEATHER
DESIRABLE PROPERTIESSHOULD SOFTEN UNIFORMLY
COLOUR SHOULD BE IN CONTRAST TO DIE MATERIAL
SHOULD NOT COME IN FLAKES WHILE WORKING
SHOULD NOT BE VERY STICKY OR SHOULD NOT CHIP WHILE CARVING
SHOULD MELTS COMPLETELY WITHOUT RESIDUE AT 500˚C
IF RESIDUE SHOULD NOT EXCED 0.10% IT ORIGINAL WEIGHT
SHOULD BE RIGID AND DIMENTIONALLY STABLE TILL ELIMINATED
FLOW
TEMP 30˚C 37˚CMIN40˚C
MAX40˚C
MIN45˚C
MAX45˚C
TYPE I 1.0% 20% 70% 90%
TYPE II1.0% 50% 70% 90%
THERMAL EXPANSION – 0.7% ABOVE 20˚C
VOLUMETRIC CONTRACTION – 0.35% ( COOLED FROM 37˚C- 25˚C )
AVERAGE COEFFICENT OF TERMAL EXPANSION – 350X10-6/˚C
THIS IS LESS IN INDIRECT WAX AS THERE IS NO TRANSITION FROM MOUTH TEMP TO ROOM TEMP
TYPE-I
LOW FLOW AT 37˚C
WORKING TEMPERATURE – 45˚C
SHOULD NOT BE HIGH TO AVOID PULPAL DAMAGE
TYPE-I
INSUFFICIENT FLOW
LACK OF DETAILS
EXCESS STRESS WITHIN
THE PATTERN
EXCESS FLOW BY
OVER HEATING MAKES
COMPRESSION OF
WAX DIFFICULT
LINEAR CONTRACT
ION MOUTH –
ROOM TEMP
TYPE I
MILDLY HEATED
PLACED IN PATIENTS MOUTH
FINGER PRESURE/BIT
E
COOLED GRADUALLY TO MOUTH
TEMP
SHOULD NOT USE COLD
WATER
TYPE II
TYPE II
HIGHER FLOW THAN THAT OF TYPE I
SHOULD USE DRY HEAT THAN WET HEAT
HAS LESS SHRINKAGE THAN TYPE I
TYPE II
DIE SHOULD BE
LUBRICATED
WAX IS MELTED AND
ADDED IN LAYERS
WAX IS CARVED
SILK / FINE CLOTH IS USED
FOR POLISHING
PATTERN IS REMOVED WITH
EXPLORER /THREAD
RPD CASTING WAXES
RPD CASTING WAXES
PARAFFIN 60%
CARNAUBA 25%
CERESIN 10%
BEE WAX 5%
CANDELILLA &
MICROCRYSTALLINE
RPD CASTING WAX (FEDERAL SPECIFICATION NO:140)FLOW 35˚C – 10%
FLOW 38˚C – 60%
BREAKING POINT - 23˚C ± 1˚C
WORKING PROPERTIESPLIABLE & ADAPTABLE AT 40˚C - 45˚C
COPY ACURATELY
NOT BRITTLE
VAPORIZE AT 500˚C
BASE PLATE WAX
COMPOSITION
80% ceresin or 70% paraffin
12% bees wax2.5% carnuaba
3% synthetic resins2.5%
microcrystalline wax
DIPPING WAX
MICROCRYSTALLINE
PROPER DETAIL AND SEALED MARGIN
HIGH ELASTICITY (MEMORY)
CLEAN BURNOUT MIN- SHRINKAGE
EXCELLENT SCRAPING ABLITY
WARPAGE: PATTENS DISTORT DUE TO STRESS RELEASE
MINIMIZING WARPAGE
•USE HIGHER TEMPERATURE AT TIME OF FORMING – LESS FORCE TO SHAPE – LESS RESIDUAL STRESSES
•SOFTEN THE WAX UNIFORMLY AT 50˚C FOR 15min
•USE WARMED CARVING INSTRUMENTS & DIE
• Provides extremely stable copings
• Material is firm to the touch but flexible like plastic
• High precision right to the margin line
• Easy to handle like normal dipping waxes
• Leaves no residue• Use only in dipping units
with UV protection covers
NEW
A LIGHT CURE DIPPING WAX
CERVICAL WAX
CERVICAL WAX
PARAFFINNATURAL
WAXES RESINS
GOOD FLOW , FITS PERFICTLY TO CERVICAL AREA
SEMI TRANSPARENT, NON- GUMMY, MEDIUM HARD & HIGH ADAPTABLITY
LOW SHRINKAGE AND LOW CONTRATION
MARGINAL WAX
SEAL MARGINS OF COPING ,CROWN & INLAY ONLAY
SPRUE WAX
MELTS COMPLETELY WITHOUT RESIDUE AT 78˚C
SCULPTURING WAX
PONTICS WAX
• Blocks of 4 Pontics• Anatomic form of the
pontics• Easy separating according
to esthetic demands• 100% wax, burns without
residue• Occlusal depth, for a
natural result• Color: Blue
PROCESSING WAXES
BOXING WAX
MELTS AT 80˚C
REGULAR – 16 mmTHIN – 14 mm
BEADING WAX
PERIPHERY WAX
• USED FOR BORDER MOLDING• FOR HYDROCOLLOID IMPRESSIONS• TACKY BUT NOT GREASY• ADHERES EASILY TO TRAYS
MODELING WAX
MODELING WAX
chewing on wax for 3 min.
( Gingival Inflammation Induced by Food and Short-chain Carboxylic Acids; J DENT RES 1998 77: 412)
The gingival crevicular fluid (GCF) then the inflammation is measured by the change in temperature
“BUT THIS IS WHAT WE DO WITH MODELING WAX”
STICKY WAX
“MODEL CEMENT” WAX GLUE
MELTS CLEAN AT 73˚C
STICKY WAX
Gum dammar (colouring matter)
Yellow bees waxRosin
Resin content
• STRONG
STRONGHARD
VERY ADHESIVE
FAST SETTING
FLOWS EASILY
OCCLUSAL RIM WAX
1.SOFT2. REGULAR3. HARD
WAX PALATE PATTERNS
• For gold, chrome, acrylic , partial or full palates
• Improves denture quality by obtaining natural living tissue finish , beautiful esthetics and greater comfort
• Less waxing and finishing (saves hand waxing)
• Convenient to use
IMPRESSION CORRECTIVE WAX
CORRECTIVE WAX
ParraffinCeresin
Bees wax
THERMOPLASTIC WAX
PENETRATION IS 100%
PENETRATION IS EXCELLENT AT 250kPa
DISTORTION SHOULD BE AVOIDED
FLUID WAX TECHNIQUE
BITE REGISTRATION WAX
Paraffin
Ceresin Bees waxTraces of
aluminium or copper particle
OTHER WAXES
RELIEF WAX
BLOCKOUT WAX
REFERENCES
• Anusavice, Philipps’: Science of dental materials, 11th edition, Elsevier• Craig RG, Powers JH: Restorative dental materials, 11th edition, Mosby• William J. O’ brien: Dental materials and their selection, 2nd edition.• Text book;Rheological Characterization of Dental Waxes; Dr. H. Weber, Dr.
J. Geis-Gerstorfer.• Thermogravimetric Analysis of Waxes; R.G. Craig, J.M. Powers and F.A.
Peyton; J DENT RES 1971 50: 450.• Dental Casting Technic: Theory and Practice : A Report To the Research
Commission of the American Dental Association; Geo C. Paffenbarger and W.T. Sweeney; J DENT RES 1931 11: 681.
REFERENCES• Differential Thermal Analysis of Commercial and Dental Waxes; R.G. Craig, J.M. Powers
and F.A. Peyton; J DENT RES 1967 46: 1090.• Effects of Changing Body Position on Dental Occlusion; Lewis F. Mc Lean, Henry S.
Brenman and M.G.F. Friedman; J DENT RES 1973 52: 1041.• Flow of Binary and Tertiary Mixtures of Waxes; R.G. Craig, J.D. Eick and F.A. Peyton; J
DENT RES 1966 45: 397.• Neutronographic Investigation of Wax Elimination from High-Temperature Investment
Molds; J.F. Walsh; J DENT RES 1977 56: 448.• Penetration of Commercial and Dental Waxes; J.M. Powers and R.G. Craig; J DENT RES
1974 53: 402.• Prosthesis of the Mouth and Face: A Symposium; V.H. Kazanjian, Arthur T. Rowe and
Harry A. Young; J DENT RES 1932 12: 651.• The Effect of Water Swaging on Stress and Strain in Dental-Wax Pattern; Gordon J.
Christensen; J DENT RES 1965 44: 930.• Thermogravimetric Analysis of Waxes; R.G. Craig, J.M. Powers and F.A. Peyton; J DENT
RES 1971 50: 450.
REFERENCES• Materials Science : Wetting Effects of Surface Treatments on Inlay Wax-
investment Combinations; J.T. Morrison, M.G. Duncanson, Jr and H.T. Shillingburg, Jr; J DENT RES 1981 60: 1858.
• Calorimetric Analysis of Commercial and Dental Waxes; J.M. Powers, R.G. Craig and F.A. Peyton; J DENT RES 1969 48: 1165.
• Characterization of Components of Dental Materials and Components of Tooth Structure by Differential Thermal Analysis; G.M. Brauer, D.J. Termini and C.L. Burns; J DENT RES 1970 49: 100.
• Dimensional Change in Wax Patterns During Setting of Gypsum Investments; George Mumford and Ralph W. Phillips; J DENT RES 1958 37: 351
• Pain Responses to Experimental Chewing in Myofascial Pain Patients; T.T.T. Dao, J.P. Lund and G.J. Lavigne; J DENT RES 1994 73: 1163.
REFERENCES• Properties of Natural Waxes Used in Dentistry; R.G. Craig, J.D. Eick and
F.A. Peyton; J DENT RES 1965 44: 1308.• Thermal Analysis of Dental Impression Waxes; John M. Powers and
Robert G. Craig; J DENT RES 1978 57: 37.• Strength Properties of Waxes at Various Temperatures and Their
Practical Application; R.G. Craig, J.D. Eick and F.A. Peyton; J DENT RES 1967 46: 300.
• Saliva, Salivary Micro-organisms, and Oral Health in the Home-dwelling Old Elderly-A Five-year Longitudinal Study; T.O. Narhi, N. Kurki and A. Ainamo; J DENT RES 1999 78: 1640
• Gingival Inflammation Induced by Food and Short-chain Carboxylic Acids; S. Kashket, J. Zhang and R. Niederman; J DENT RES 1998 77: 412
THANKYOU