Transcript Dental alloys

Dental alloys
• A number of alloys are used in Dental
technology to suit multiple applications
A typical high Gold (Au) alloy for
ceramics ( BIOclus 4)
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Typical Components
Au 85.8%
Platinum 11%
Zinc 0.5%
Indium 1.7% (Soluble with porcelain)
Rhodium 0.7%
• Melting range 1040-1140°C
A typical white Au alloy for ceramics
(Degudor)
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Will include
Au 55.1%
Palladium 34.5%
Indium 9%
Iridium 0.2%
• Melting range 1190-1275°C
A Non-precious bonding alloy
(Matchmate NP10) contains…
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Cobalt 61%
Chromium 28%
Tungsten 8.5%
Silicon 1.6%
Carbon 0.1%
Manganese 0.25%
Iron 0.5%
• Melting range 1320-1420°C
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A high Au (Gold-coloured) crown &
bridge alloy (Degulor C)… may
contain
Au 74%
Platinum 2.4%
Palladium 2.0%
Ag 13.5%
Copper (Cu) 7.0%
Zinc 1.0 %
Iridium
• Melting range 900-975°C
A reduced Au (silver-coloured) crown &
bridge alloy (Stabilor IV plus)… will contain
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Au 62.2%
Platinum 4.4%
Silver 22.5 %
Copper 9.8%
Zinc 1%
Iridium 0.1%
• Melting range 870-925°C
A typical Chrome alloy for a denture
(Biosil I) ..may include
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Cobalt 62.5%
Chrome 30.5%
Molybdenum 5.0%
Silicon (Si) 1.0%
Manganese 0.4%
Carbon 0.3%
Nitrogen 0.3%
• Melting range 1290-1390°C
An Orthodontic Stainless Steel wire
for cold working will contain…
Containing a chemical range of…
• Iron 70.8%
• Nickel (Ni) 10%
• Chromium 16%
• Molybdenum 2%
• Silicon 1%
• Carbon 0.08%
• Phosphorous (P) 0.045
• Sulphur 0.03%
Properties of constituents…
Copper
• Increases alloy hardness and strength…increases
the CTE (thermal co-efficiency) important for a
ceramic bonding alloy.
Gold Au
• Main component of precious-metal dental
alloys. Extremely stable intraorally, extremely
resistant to corrosion
Indium
• Improves mechanical properties, increases the
CTE, excellent flow characteristics
Iridium
• Decreases alloy grain size. Heat resistance,
temperability (to alter properties) and melting
range are all increased.
Manganese
• Decreases the grain size and increases the
strength of the alloy
Palladium
• Homogenizes the alloy and increases its
hardness, strength, corrosion resistance and
overall intraoral stability, increases the melting
range
Platinum
• Increases intraoral stability, hardness and heat
resistance and decreases particle size, reduces
the oxide layer.
Rhodium
• Decreases the grain size, increases hardness,
improves flow characteristics and temperability
Silver
• Improves flow characteristics and increases
hardness, improves soldering properties and
increases the CTE.
Zinc
• Improves mechanical properties and flow
characteristics, decreases the melting
temperature
Cobalt
• Extremely hard element protected from
oxidizing through a passive forming protective
oxide.
Chromium
• Most abundant element, odourless and tasteless
extremely hard and corrosion resistant
Molybendum
• Hard and stable, often a key component in highstrength alloys.
Steel
• Formed from Iron & carbon