1.13 Metal Alloys for Orthodontics, Prosthodontics, and Pediatric Pedodontics

Non-noble

Which types of metals are used for instruments, to prepare teeth for restorations, and to place restorations?

Noble metals

Gold, platinum, and palladium are which types of metal that are used infrequently in orthodontics and pedodontics

• High strength and durability

• Ductility

• Stiffness

• Corrosion resistance

What are characteristics that base alloys should exhibit?

Stainless steel

What is the most popular metal used in orthodontics and pediatrics due to its cost and ease of handling?

• Crowns for primary molars

• Bands, brackets, and wires for orthodontics

• Space maintainers

• Retainers

• Restorative, orthodontics, and prophylactic instruments

• Burs, instrument trays

What are uses of stainless steel in dentistry?

Chromium

What is the element of stainless steel that makes it tarnish and corrosion resistant?

Passivation

A protective coating that’s formed from a reaction of chromium and oxide that creates a film over the metal

Titanium alloys

Which alloy type is the least susceptible to pitting?

• Orthodontics wires

• Frameworks for partials

What are uses of cobalt-chromium alloys?

True

T/F: Denture cleansers that have chlorine products should not be used on dentures or partials with any type of base metal

• Orthodontics wires

• Implant materials

• Instruments

What are uses of titanium and titanium alloys in dentistry?

• Stainless steel

• Cobalt-chromium

• Nickel-titanium

• Beta-titanium

What alloys are used for ortho wires?

True

T/F: Passivation is a process that also occurs in titanium and its alloys, making it corrosion resistant and biocompatible

• Base structure for PFMs

• Resin-bonded bridges

What are the uses of nickel-chromium alloys in dentistry?

Elastic limit

How much elastic deformation can take place before the wire is permanently deformed

Elastic modulus

How difficult it is to bend a wire

Resilience

How much energy is stored in the wire that can be used to move the teeth

Working range

How much tooth movement occurs before the wire must be repositioned/adjusted

Ductility

How much can the wire be shaped/bent before it breaks

True

T/F: In ortho, it is most ideal for tooth movement to occur slowly and with low force applications

Welding

The joining of 2 metals requiring no intermediate agent

Solder

A procedure to weld two metals using a metallic material to join the two metals

True

T/F: A disadvantage of base metal alloys that are greater than gold is that it can wear down opposing dentition and it’s more difficult to adjust