Artificial teeth

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ARTIFICIAL TEETHARTIFICIAL TEETHARTIFICIAL TEETHARTIFICIAL TEETH PRESENTED BY

DR. HASHMAT GUL

DEMONSTRATOR, AMC,

DENTAL MATERIALS.

INTRODUCTIONINTRODUCTIONINTRODUCTIONINTRODUCTION� Constitute one of the main components of Denture....

�COMMONLY USED MATERIALSCOMMONLY USED MATERIALSCOMMONLY USED MATERIALSCOMMONLY USED MATERIALS

�Acrylic

�Porcelain

�Composite

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IDEAL REQUIREMENTS IDEAL REQUIREMENTS IDEAL REQUIREMENTS IDEAL REQUIREMENTS 1). ). ). ). ESTHETICSESTHETICSESTHETICSESTHETICS

� Should ideally match the Natural teeth in shape , color & translucency.

2). 2). 2). 2). GOOD ATTACHMENT TO DENTURE BASEGOOD ATTACHMENT TO DENTURE BASEGOOD ATTACHMENT TO DENTURE BASEGOOD ATTACHMENT TO DENTURE BASE

3). 3). 3). 3). LOW DENSITYLOW DENSITYLOW DENSITYLOW DENSITY

� Light weight dentures.

4). 4). 4). 4). STRONG & TOUGH STRONG & TOUGH STRONG & TOUGH STRONG & TOUGH To resist fracture.

5). 5). 5). 5). RESIST ABRASIONRESIST ABRASIONRESIST ABRASIONRESIST ABRASION during Chewing & Cleaning.

6). 6). 6). 6). ALLOW EASY CHAIRALLOW EASY CHAIRALLOW EASY CHAIRALLOW EASY CHAIR----SIDE ADJUSTMENTSSIDE ADJUSTMENTSSIDE ADJUSTMENTSSIDE ADJUSTMENTS to adjust occlusion....

7). 7). 7). 7). RESIST STAININGRESIST STAININGRESIST STAININGRESIST STAINING

COMPOSITIONCOMPOSITIONCOMPOSITIONCOMPOSITIONACRYLIC TEETHACRYLIC TEETHACRYLIC TEETHACRYLIC TEETH

POWDERPOWDERPOWDERPOWDER

�Polymer, Polymer, Polymer, Polymer, PMMA

�Initiator, Initiator, Initiator, Initiator, Benzyoyl peroxide

�PigmentsPigmentsPigmentsPigments

LIQUIDLIQUIDLIQUIDLIQUID

� MonomerMonomerMonomerMonomer, MMA

� CrossCrossCrossCross----linking agentlinking agentlinking agentlinking agent, Ethylene-glycol-dimethacrylate.

� Inhibitor, Inhibitor, Inhibitor, Inhibitor, Hydroquinone.

� Activator, Activator, Activator, Activator, N N′-dimethyl-p-toluidine.

PORCELAIN TEETHPORCELAIN TEETHPORCELAIN TEETHPORCELAIN TEETH

�Clay Clay Clay Clay (Kaolin)

�SilicaSilicaSilicaSilica

�BinderBinderBinderBinder (Feldspar)

�GlassesGlassesGlassesGlasses

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FABRICATIONFABRICATIONFABRICATIONFABRICATIONACRYLIC TEETHACRYLIC TEETHACRYLIC TEETHACRYLIC TEETH

�Reusable metal molds using

� Dough Molding Technique.

� Injection Molding Technique.

�Highly cross-linked resins used to resist crazing.

PORCELAIN PORCELAIN PORCELAIN PORCELAIN TEETHTEETHTEETHTEETH

�Fabrication involves

� Compaction

� Firing

�Standard shapes & sizes produced by using molds 30% larger than required to allow shrinkage during firing.

�Small holes or metal pins are incorporated in the base of Porcelain teeth during their production Mechanical attachment.

ADVANTAGES OF ADVANTAGES OF ADVANTAGES OF ADVANTAGES OF ACRYLIC TEETHACRYLIC TEETHACRYLIC TEETHACRYLIC TEETH

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ADVANTAGES ADVANTAGES ADVANTAGES ADVANTAGES OF ACRYLIC OF ACRYLIC OF ACRYLIC OF ACRYLIC TEETHTEETHTEETHTEETH 1) Easy to adjust and adjust and adjust and adjust and trimtrimtrimtrim

2)2)2)2) Chemical bondingChemical bondingChemical bondingChemical bonding to denture base, as they are made of the same material

3) Acrylic teeth are more compatiblecompatiblecompatiblecompatible with the denture base than porcelain teeth.

4) No clicking sound.

ADVANTAGES ADVANTAGES ADVANTAGES ADVANTAGES OF ACRYLIC OF ACRYLIC OF ACRYLIC OF ACRYLIC TEETHTEETHTEETHTEETH 5) Easy to fabricatefabricatefabricatefabricate

6)6)6)6) Less Less Less Less traumatraumatraumatrauma to denture-bearing area. This is particularly crucial for people with implants supporting the fake tooth. If they have lost bone or gum tissues around the implant, acrylic teeth are more forgiving when you grind your teeth, and will hold their position longer than porcelain teeth.

7) Dentures made with acrylic teeth are lighterlighterlighterlighter.

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DISADVANTAGES OF DISADVANTAGES OF DISADVANTAGES OF DISADVANTAGES OF ACRYLIC TEETHACRYLIC TEETHACRYLIC TEETHACRYLIC TEETH

DISADVANTAGES DISADVANTAGES DISADVANTAGES DISADVANTAGES OF ACRYLIC OF ACRYLIC OF ACRYLIC OF ACRYLIC TEETHTEETHTEETHTEETH 1) Acrylic teeth are susceptible to abrasionsusceptible to abrasionsusceptible to abrasionsusceptible to abrasion, e.g. if the

patient has a habit of teeth-grinding (bruxism) or eats rough diets, the teeth will wear down with time, causing changes in the length of the teeth.

2)2)2)2) Easily Easily Easily Easily stainedstainedstainedstained, as they contain microscopic pits that can hold bacteria

3) In rebasing, difficult to removedifficult to removedifficult to removedifficult to remove acrylic teeth from the denture base

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ADVANTAGES OF ADVANTAGES OF ADVANTAGES OF ADVANTAGES OF PORCELAIN TEETHPORCELAIN TEETHPORCELAIN TEETHPORCELAIN TEETH

ADVANTAGES ADVANTAGES ADVANTAGES ADVANTAGES OF PORCELAIN OF PORCELAIN OF PORCELAIN OF PORCELAIN TEETHTEETHTEETHTEETH 1) Although both acrylic and porcelain teeth can be made

to give a natural appearance, the slightly greater greater greater greater translucency and depth of colortranslucency and depth of colortranslucency and depth of colortranslucency and depth of color achieved with porcelain, gives this material a slight advantage.

2)2)2)2) HarderHarderHarderHarder than acrylic more durable.

3)3)3)3) Resist wearResist wearResist wearResist wear- this preserves the normal jaw movements and alignment for a longer period.

4)4)4)4) Resist stainingResist stainingResist stainingResist staining

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ADVANTAGES ADVANTAGES ADVANTAGES ADVANTAGES OF PORCELAIN OF PORCELAIN OF PORCELAIN OF PORCELAIN TEETHTEETHTEETHTEETH 5) Occasionally, due to resorption of the edentulous

ridges, the denture becomes loose and does not fit the mouth at all. Instead of remaking a new denture, the base of the denture can be replaced (called “rebasingrebasingrebasingrebasing”) while retaining the artificial teeth so that the Occlusion will not be altered. Because porcelain teeth do not bond chemically to the base, they are easily easily easily easily removed from the removed from the removed from the removed from the basebasebasebase for this purpose.

DISADVANTAGES OF DISADVANTAGES OF DISADVANTAGES OF DISADVANTAGES OF PORCELAINPORCELAINPORCELAINPORCELAIN TEETHTEETHTEETHTEETH

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DISADVANTAGESDISADVANTAGESDISADVANTAGESDISADVANTAGESOF PORCELAINPORCELAINPORCELAINPORCELAINTEETHTEETHTEETHTEETH

1) Noisyoisyoisyoisy: clicking sounds are made when porcelain teeth comes into occlusion with another porcelain tooth

2)2)2)2) BrittleBrittleBrittleBrittle – more likely to fracture than acrylic teeth

3)3)3)3) Do Do Do Do not bond chemicallynot bond chemicallynot bond chemicallynot bond chemically to denture base –Small holes or metal pins are incorporated in the base of porcelain teeth during their production to enable mechanical bonding mechanical bonding mechanical bonding mechanical bonding to the denture base.

DISADVANTAGESDISADVANTAGESDISADVANTAGESDISADVANTAGESOF PORCELAINPORCELAINPORCELAINPORCELAINTEETHTEETHTEETHTEETH

4)4)4)4) Not as compatibleNot as compatibleNot as compatibleNot as compatible as acrylic teeth with the basewith the basewith the basewith the base of the denture – There is a serious mismatch in coefficient of thermal and modulus of elasticity between porcelain and acrylic resin. This may lead to crazing and cracking crazing and cracking crazing and cracking crazing and cracking of the denture base in the region around the base of the porcelain teeth.

5) Its density value is about twice that of acrylic teeth; dentures constructed with porcelain teeth are much heavierheavierheavierheavier.

6) Difficult to fabricatefabricatefabricatefabricate

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DISADVANTAGES DISADVANTAGES DISADVANTAGES DISADVANTAGES OF PORCELAIN OF PORCELAIN OF PORCELAIN OF PORCELAIN TEETHTEETHTEETHTEETH

7) Difficult to trimtrimtrimtrim, due to the hardness of this material.

8) Porcelain teeth exert more force to the underlying supporting soft tissues, causing more traumatraumatraumatrauma to these tissues. This is a function of the greater modulus of elasticity of porcelain. This trauma is capable of accelerating the rate by which the underlying bone resorbs.

9) If a denture is going to be worn against opposing natural opposing natural opposing natural opposing natural teethteethteethteeth than plastic teeth should be selected because porcelain teeth, being harder, could excessively wear natural excessively wear natural excessively wear natural excessively wear natural teethteethteethteeth away.

DIFFERENCE BETWEEN DIFFERENCE BETWEEN DIFFERENCE BETWEEN DIFFERENCE BETWEEN ACRYLIC & PORCELAIN ACRYLIC & PORCELAIN ACRYLIC & PORCELAIN ACRYLIC & PORCELAIN TEETHTEETHTEETHTEETH

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DIFFERENCE BETWEEN ACRYLIC & DIFFERENCE BETWEEN ACRYLIC & DIFFERENCE BETWEEN ACRYLIC & DIFFERENCE BETWEEN ACRYLIC & PORCELAIN TEETHPORCELAIN TEETHPORCELAIN TEETHPORCELAIN TEETH

PROPERTIESPROPERTIESPROPERTIESPROPERTIES ACRYLIC TEETHACRYLIC TEETHACRYLIC TEETHACRYLIC TEETH PORCELAIN TEETHPORCELAIN TEETHPORCELAIN TEETHPORCELAIN TEETH

1). Aesthetics � A more realistic Customized

appearance can be achieved.

� Good but not long-lasting.

� Easily stained/discolored.

� A more realistic Customized

appearance can be achieved.

� Better & long-lasting.

�Greater translucency.

�Depth of color.

2). Clicking sound � Absent. � Present.

3). Attachment Mechanism � Chemical adhesion to DB.

� More Compatible with DB

material.

� Mechanical retention to DB.

� Less Compatible with DB.



4). Coefficient of Thermal

Expansion & Modulus of

Elasticity.

� Same as DB. � Serious mismatch With DB.

� Crazing or cracking of DB.

5). Density/weight � Match with DB.

� Dentures are lighter.

� Twice that of Acrylic Resin.

� Dentures are much heavier.

6). Brittleness/Strength � Less brittle.

� Better impact strength.

� More brittle so, easily

chip/fracture.

� Poor impact strength.

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PROPERTIESPROPERTIESPROPERTIESPROPERTIES ACRYLIC TEETHACRYLIC TEETHACRYLIC TEETHACRYLIC TEETH PORCELAIN TEETHPORCELAIN TEETHPORCELAIN TEETHPORCELAIN TEETH7). Hardness/Wear � Less hard , suffer abrasion.

� Wear out with time.

� Much harder, no abrasion.

� Much durable.

� Teeth easily removed for

re-basing if required.

8). Adjustability � Easily adjusted by grinding.

� Easily polished following

adjustment.

� Difficult to adjust

� On grinding glaze is lost.

� Difficult to polish.

9). Cost � Cheap � Costly



10). Biocompatibility � Inert in oral environment.

� Transmit less forces to

underlying tissues due to

low modulus of elasticity.

� Preferred for people having

bone loss in jaws/unhealthy

gums.

� Partial denture opposing

intact arch Acrylic

teeth preferred.

� Inert in oral environment.

� Transmit greater forces to

underlying tissues due to

high modulus of elasticity

leading to bone loss.

� Abrade/damage the

opposing Natural tooth, so

contraindicated in dentures

opposing intact dental arch.

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IMPORTANT TIPSIMPORTANT TIPSIMPORTANT TIPSIMPORTANT TIPS

CLEANING OF DENTURESCLEANING OF DENTURESCLEANING OF DENTURESCLEANING OF DENTURES

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CLEANING OF DENTURESCLEANING OF DENTURESCLEANING OF DENTURESCLEANING OF DENTURES

Health & Medicine

Artificial teeth