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SUMITA
FINAL YEAR BDS
1. CLASSIFICATION ACCORDING TO THE
STRUCTURE OF ORTHODONTIC MATERIAL
2. CLASSIFICATION ACCORDING TO USAGE
METALLIC MATERIAL CERAMIC MATERIAL POLYMERIC MATERIAL
1.Wire alloys 1.ceramic brackets 1.polycarbonates
for
2.Orthodontic bands 2.filler particles in cements brackets
3.Orthodontic brackets 2.adhesive resin
for
bonding
3.polyurethane
elastomers
for
tooth
movement
3.IMPRESSION MATERIAL:
Alginate
4. Ortho plaster
5.Bonding material:
GIC ( luting)
1.Metal alloys:
Gold,platinum,palladium
2.Stainless steel
3.cobalt-chromium alloys
4.nickel-titanium alloys
5.Beta titanium
6.Optiflex archwire
1. High strength
2. High range
3. High formability
4. Low stiffness
5. Reasonable cost
1. Gold alloys exhibit excellent formability
2. Biocompatibility
3. Low spring back
4. High cost
 COMPOSITION:
fe = 71%
chromium = 18%
nickel = 8%
carbon = <0.2%
1. It is most popular and widely used arch
wire in orthodontics
2. Inexpensive
3. Corrosion resistance due to increased
chromium content
4. It has good stiffness but poor spring back
because of rigidity
5. SS can be softened by annealing and
hardening by cold working
 COMPOSITION:
COBALT=40%
CHROMIUM=20%
Ni=15%
Fe=7%
 TYPES:
1. BLUE (SOFT/EASY TO BEND)
2. YELLOW(DUCTILE)
3. GREEN(SEMI RESILIENT)
4. RED(RESILIENT)
1. It is soft and formable
2. It can be hardened and strengthened by
heat treatment
3. Less spring back when compared to SS
4. Good stiffness
5. Good formability(doesn’t fracture)
 COMPOSITION:
Ni=52%
Ti=43%
cobalt=3%
 PROPERTIES:
1. Super elasticity
2. Shape memory ( it returns to its original shape after
deformation)
3. High spring back , high working range , low stiffness
4. Disadvantage is , it is resistant to taking a bend ,
helices or loops cannot be made on them
5. They cannot be soldered or welded.
 COMPOSITION:
Ti=79%
MOLYBDENUM=11%
Zn=6%
 PROPERTIES:
1. It is very good for nickel sensitive patients bcz it is
nickel free.
2. Modulus of elasticity is less than SS twice greater than
niti =good strength
3. Good formability = less fracture)
4. It can be welded but cannot be soldered
5. It has more friction compared to SS and Niti.
1. These arch wire are made of clear optical
fiber
2. Highly esthetic
3. Highly resilience
4. Draw back is it cannot accept a sharp bend
1. Bands are passive component that help in
fixing the various attachments onto the
teeth
2. Made up of stainless steel
1.Metallic bracket
2.Ceramic bracket
METALLIC BRACKETS
ADVANTAGES:
1. They can be recycled
2. They can be sterilized
3. They resist deformation and fracture
4. They exhibit the least friction at the wire bracket
interface
5. They are not very expensive
DISADVANTAGE:
1. They are not esthetically pleasing
2. They can corrode and cause staining of teeth
CERAMIC BRACKETS:
They are made up of aluminium oxide and zirconium
oxide.
ADVANTAGES:
1. Dimensionally stable
2. They are durable and resist staining in the oral
environment
DISADVANTAGES:
1. Brittle therefore fracture or crack occurs when
undue forces are applied
2. Greater friction
PLASTIC BRACKETS:
They are made up of polycarbonate or modified form of
polycarbonate
These were introduce for esthetic purpose
Available in tooth colored or transparent forms
DISADVANTAGES:
1. Discoloration in pts who smoke or drink coffee
2. Poor dimensional stability
3. Slots tend to distort
4. Friction is high
ELASTIC CHAIN:
Made up of synthetic polyeurythene material.
ELASTIC THREAD:
Made up of latex
< both are used for space closure.
1. Most widely used impression material
2. Irreversible hydrocolloid
ADVANTAGES:
1. Easy to manipulate
2. Relatively inexpensive
3. Comfortable for the patient
4. Pleasant taste
DISADVANTAGE:
1. Tear easily
2. Models should be poured immediately
DIRECT BONDING
THANKYOU

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Materials in orthodontics (2)

  • 2. 1. CLASSIFICATION ACCORDING TO THE STRUCTURE OF ORTHODONTIC MATERIAL 2. CLASSIFICATION ACCORDING TO USAGE
  • 3. METALLIC MATERIAL CERAMIC MATERIAL POLYMERIC MATERIAL 1.Wire alloys 1.ceramic brackets 1.polycarbonates for 2.Orthodontic bands 2.filler particles in cements brackets 3.Orthodontic brackets 2.adhesive resin for bonding 3.polyurethane elastomers for tooth movement
  • 4.
  • 5. 3.IMPRESSION MATERIAL: Alginate 4. Ortho plaster 5.Bonding material: GIC ( luting)
  • 6. 1.Metal alloys: Gold,platinum,palladium 2.Stainless steel 3.cobalt-chromium alloys 4.nickel-titanium alloys 5.Beta titanium 6.Optiflex archwire
  • 7. 1. High strength 2. High range 3. High formability 4. Low stiffness 5. Reasonable cost
  • 8. 1. Gold alloys exhibit excellent formability 2. Biocompatibility 3. Low spring back 4. High cost
  • 9.  COMPOSITION: fe = 71% chromium = 18% nickel = 8% carbon = <0.2%
  • 10. 1. It is most popular and widely used arch wire in orthodontics 2. Inexpensive 3. Corrosion resistance due to increased chromium content 4. It has good stiffness but poor spring back because of rigidity 5. SS can be softened by annealing and hardening by cold working
  • 11.  COMPOSITION: COBALT=40% CHROMIUM=20% Ni=15% Fe=7%  TYPES: 1. BLUE (SOFT/EASY TO BEND) 2. YELLOW(DUCTILE) 3. GREEN(SEMI RESILIENT) 4. RED(RESILIENT)
  • 12. 1. It is soft and formable 2. It can be hardened and strengthened by heat treatment 3. Less spring back when compared to SS 4. Good stiffness 5. Good formability(doesn’t fracture)
  • 13.  COMPOSITION: Ni=52% Ti=43% cobalt=3%  PROPERTIES: 1. Super elasticity 2. Shape memory ( it returns to its original shape after deformation) 3. High spring back , high working range , low stiffness 4. Disadvantage is , it is resistant to taking a bend , helices or loops cannot be made on them 5. They cannot be soldered or welded.
  • 14.  COMPOSITION: Ti=79% MOLYBDENUM=11% Zn=6%  PROPERTIES: 1. It is very good for nickel sensitive patients bcz it is nickel free. 2. Modulus of elasticity is less than SS twice greater than niti =good strength 3. Good formability = less fracture) 4. It can be welded but cannot be soldered 5. It has more friction compared to SS and Niti.
  • 15. 1. These arch wire are made of clear optical fiber 2. Highly esthetic 3. Highly resilience 4. Draw back is it cannot accept a sharp bend
  • 16. 1. Bands are passive component that help in fixing the various attachments onto the teeth 2. Made up of stainless steel
  • 18. METALLIC BRACKETS ADVANTAGES: 1. They can be recycled 2. They can be sterilized 3. They resist deformation and fracture 4. They exhibit the least friction at the wire bracket interface 5. They are not very expensive DISADVANTAGE: 1. They are not esthetically pleasing 2. They can corrode and cause staining of teeth
  • 19. CERAMIC BRACKETS: They are made up of aluminium oxide and zirconium oxide. ADVANTAGES: 1. Dimensionally stable 2. They are durable and resist staining in the oral environment DISADVANTAGES: 1. Brittle therefore fracture or crack occurs when undue forces are applied 2. Greater friction
  • 20. PLASTIC BRACKETS: They are made up of polycarbonate or modified form of polycarbonate These were introduce for esthetic purpose Available in tooth colored or transparent forms DISADVANTAGES: 1. Discoloration in pts who smoke or drink coffee 2. Poor dimensional stability 3. Slots tend to distort 4. Friction is high
  • 21. ELASTIC CHAIN: Made up of synthetic polyeurythene material. ELASTIC THREAD: Made up of latex < both are used for space closure.
  • 22. 1. Most widely used impression material 2. Irreversible hydrocolloid ADVANTAGES: 1. Easy to manipulate 2. Relatively inexpensive 3. Comfortable for the patient 4. Pleasant taste
  • 23. DISADVANTAGE: 1. Tear easily 2. Models should be poured immediately
  • 25.