ceramics for dental use

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Ceramics for dental use

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ICB

Dental School

classification of ceramics for dental use

Dra. Analy Solano Zaragoza Dr. Alfredo Nevárez Rascón

Ceramics

Formed from inorganic nature nonmetals, which are obtained by the action of heat and whose final structure is partially or completely crystalline.

Main components: • Feldspar (81%)

• Quartz (15%)

• kaolin (4%)

•Metal oxides

FIG 1:

http://www.google.com.mx/imgres?q=

feldespato

FIG 2:

http://www.google.com.mx/imgres?q=cuarzo

FIG 3:

http://www.google.com.mx/imgres?q=caolin

Feldspar

When broken glass, is responsible for the translucency of porcelain.

Serve as a matrix of quartz

Melts at 1300 C

Tends to react with heat, spent time distorting the piece turn white and shade.

FIG 4: http://www.google.com.mx/imgres?q=feldespato

The quartz Constitutes

the crystalline

face

Hardening of

the mass

Is used as filler

The kaolin Increases the ability of the porcelain mold

before baking

Reacts with the feldspar and gives rigidity

Facilitates mixing with water while

maintaining the form during drying and

firing.

FIG 5: Mat Caolin

http://www.google.com.mx/imgres?q=caolin

Metal oxides

Copper: green

Cobalt: blue

Titanium: yellow-brown

Magnesium lavender blue

Zirconium, titanium and tin:

opacacidad

Iron oxide: brown

Majority of dental ceramics:

Have a mixed structure.

Formed by a glassy matrix (whose atoms are disordered).

Massive particles are more or less large crystallized minerals (whose atoms are arranged uniformly if).

FIG 6

http://scielo.isciii.es/pdf/rcoe/v12n4/revision1.pdf

Classification by chemical composition.

Feldspathic ceramics:

composition. feldspar: translucency

Quartz: Crystalline

The kaolin: confer plasticity and facilitates the management of the ceramic when not yet sintered.

FEATURES:

Excellent optical properties

Relative fragile.

Mainly used for coating metal or ceramic structures.

FIG 7 :

http://www.google.com.mx/imgres?q=ceramicas+f

eldespaticas

PROPERTIES OF feldspathic

Greater resistance.

Contain the quartz and kaolin

Ceramic mass incorporated elements that

increase the mechanical strength

In1965, Hughes joined M

cLean

and feldspathic porcelain

quantities of aluminum

oxide by reducing the

proportion of quartz.

Improved toughness.

Exceeds 50% alumina is

produced a significant

increase in opacity

Zirconia Ceramics

Composed of highly sintered zirconia (95%), partially

stabilized with yttrium oxide (5%).

High toughness by the crystalline microstructure

Opaque (no glassy phase)

Main structure for the core of the restoration.

FIG 8: Diferencie

http://www.google.com.mx/imgres?q=ceramicas+zirconi

o

vitro ceramic

Molded to desired shape.

Translucent glassy aesthetic.

Fragile.

Manufacture in glassy state, non-crystalline and is subsequently converted to the crystalline state by heat treatment.

FIG 9:

http://www.google.com.mx/imgres?q=vitroceramicas

Classification according to the preparation technique

Refractory dye and Condensation Design model of primary impression resistant,

to dimensional changes during the heat treatment.

porcelain is applied to refractory models to sintered

And final corrections.

FIG 10:

http://www.google.com.mx/imgres?q=mu

%C3%B1%C3%B3n+refractario

FIG 11:

http://www.google.com.mx/imgres?q=mu%C3%

B1%C3%B3n+refractario

Replacing a lost wax technique

Waxed the

pattern which may be the inner cap or full restoration introduced into a cylinder and calcined wax.

The ceramic is heated to its melting point

Ceramic injection is pushes it into the mold.

Fig 12:

http://www.google.com.mx/imgres?q=cera+p%C

3%A9rdida+de+uso+odontologico

Fig 13:

http://www.google.com.mx/imgres?q=cera

Computer-assisted technology

Composed of 3 phases:

scanning, design and machining.

Scanning: Recorded three-dimensional by using cameras or sapphire tip.

Design: In the computer using specialized software.

Machining: milling in a unit that transfers the dimensions of the software and makes the model.

Fig 14: CAD CAM

http://metal-engravings.com/metal-

engraving/cad-cam-2.html

ADVANTAGES DISADVANTAGES

• Translucency • Low resisteance to the impact

• Chemical Stability • Low tencional resisteance

• Thermal expansion

coefficient close to the tooth

• Fragil

• Biocompatibility • Porosity

• High compressive strength and

abrasion.

• Contraction

• Good marginal fit

Trade marcs

DC-Zircon

In- Ceram YZ

Lava (3M Espe)

Biodent (dentsply)

Cerinat ( Dent- mat)

Ceramco ll ( Ceramco)

Fortune ( Williams)

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