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www.indiandentalacademy.com
ACKNOWLEDGEMENT
INDIAN DENTAL ACADEMY
Leader in continuing dental education
www.indiandentalacademy.com
www.indiandentalac...
Introduction
Orthodontic therapy is a force
management procedure, largely
based on the use of wires.
Wires are a mainstay ...
•Ideally, archwires are designed to
move teeth with light continuous forces.
•It is important that the forces do not
decre...
LOOPED VS NiTi
• Tissue injury
• Unhygienic
environment
• Fabrication complexity
• Time consuming
www.indiandentalacademy....
Evolution of NI-TI alloys
Buehler’s preliminary results led to the
development of the first Ni-Ti orthodontic
alloy by pio...
• Chinese Ni-Ti – the General Research Institute
for Non-ferrous Metals –(1978)
• Japanese Ni-Ti – the Furukawa Electric
C...
Wire characteristics and
clinical relevance.
• Large spring back
• Low stiffness
• High Formability
• High Stored Energy
•...
Atomic structure of Ni-Ti
The crystallographic,tri-dimensional lattice of
the Ni-Ti alloy is present in 2 phases:
Martensi...
• Ni-Ti alloys has a specific
temperature range in which the phase
transition takes place from the
austenite to the marten...
SHAPE MEMORY is a
phenomenon whereby the
alloy is soft and readily
formable at a low temp.,but
can easily be returned to i...
…An interesting feature of shape
memory
• Through deflection and repeated temp.
cycles, the wire in the austenitic phase i...
Superelasticity
Superelasticity is a phenomenon wherein the
stress remained nearly constant despite the strain
change with...
Pseudoelasticity –stress-related
behavior of Ni-Ti
• The deflection in an austenitic archwire at oral temp.
generates a lo...
Cu Ni-Ti…Advancing towards
ideal archwire
• Cu Ni-Ti alloy wire
represents a major
advancement in shape
memory wires by
re...
Role of Copper :-
• Cu enhances the thermal reactive
properties of Ni-Ti alloys thus
providing equal loading (engaging)
an...
Configuration of available Superelastic
Ni-Ti and Heat-activated Ni-Ti
Round Ni-Ti Rectangular & Square
Ni-Ti
www.indiande...
After
Before
www.indiandentalacademy.com
After
Before
www.indiandentalacademy.com
www.indiandentalacademy.com
www.indiandentalacademy.com
Recycling of Ni-Ti
Recycling involves
• Repeated exposure of the wire for
several weeks or months to mechanical
stresses a...
• Heat sterilization is the most reliable
method - (Steam autoclaving at
1210
C,15-20psi for 20 min)
• Chemical sterilizat...
Advantages of Ni-Ti
Fewer archwire changes
Less chair side time
Reduction in time required to
accomplish rotations and ...
Limitations to use of Ni-Ti
Poor formability
Fractures readily when bent over sharp
edge and effects springback property...
…and to conclude
In contemporary
practice no one
archwire material
meets all ideal
requirements and the
best results are
o...
www.indiandentalacademy.com
Thank you
For more details please visit
www.indiandentalacademy.com
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Intelligent archwire 3 /certified fixed orthodontic courses by Indian dental academy

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The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.

Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078

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Intelligent archwire 3 /certified fixed orthodontic courses by Indian dental academy

  1. 1. www.indiandentalacademy.com
  2. 2. ACKNOWLEDGEMENT INDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com www.indiandentalacademy.com
  3. 3. Introduction Orthodontic therapy is a force management procedure, largely based on the use of wires. Wires are a mainstay in storing and distributing the therapeutic force to the teeth thus bringing them to the ideal function and esthetic position. www.indiandentalacademy.com
  4. 4. •Ideally, archwires are designed to move teeth with light continuous forces. •It is important that the forces do not decrease rapidly. •Light forces reduce patient discomfort, tissue hyalinization and undermining resorption. www.indiandentalacademy.com
  5. 5. LOOPED VS NiTi • Tissue injury • Unhygienic environment • Fabrication complexity • Time consuming www.indiandentalacademy.com
  6. 6. Evolution of NI-TI alloys Buehler’s preliminary results led to the development of the first Ni-Ti orthodontic alloy by pioneers such as ANDREASEN and his colleagues. The engineering of nickel- titanium alloys has made remarkable progress since the original work of BUEHLER for the Naval Ordinance Laboratory in the early 1960’s. www.indiandentalacademy.com
  7. 7. • Chinese Ni-Ti – the General Research Institute for Non-ferrous Metals –(1978) • Japanese Ni-Ti – the Furukawa Electric Company Ltd – Japan (1978) • Copper Ni-Ti – Rohit Sachdeva (1995) These advanced alloys have different transition temperatures and present a phase transformation. Further research led to the advent of Superelastic and Thermodynamic Ni-Ti alloys. www.indiandentalacademy.com
  8. 8. Wire characteristics and clinical relevance. • Large spring back • Low stiffness • High Formability • High Stored Energy • Biocompatibility • Environmental Stability www.indiandentalacademy.com
  9. 9. Atomic structure of Ni-Ti The crystallographic,tri-dimensional lattice of the Ni-Ti alloy is present in 2 phases: Martensite phase:the lattice is body-centered (cubic or tetragonal) Austenitic phase: the lattice is face - centered (hexagonal close packed) An intermediate rhombohedral ‘R’phase with a simple hexagonal lattice has also been identified.www.indiandentalacademy.com
  10. 10. • Ni-Ti alloys has a specific temperature range in which the phase transition takes place from the austenite to the martensitic phase(reversible change) and this TTR contributes to the shape memory effect of Ni-Ti alloys. www.indiandentalacademy.com
  11. 11. SHAPE MEMORY is a phenomenon whereby the alloy is soft and readily formable at a low temp.,but can easily be returned to its original configuration when heated to a suitable TTR. www.indiandentalacademy.com
  12. 12. …An interesting feature of shape memory • Through deflection and repeated temp. cycles, the wire in the austenitic phase is able to “memorize”a preformed shape. • By lowering the temp.,the alloy is transformed into martensite and becomes pliable and easily deformed. • However, every time the temp. rises above austenitic phase,the wire will remember and recover the ideal arch-form.www.indiandentalacademy.com
  13. 13. Superelasticity Superelasticity is a phenomenon wherein the stress remained nearly constant despite the strain change within a specific range. • This allows a constant force to be delivered over an extended portion of the deactivation range,and is therefore more likely to generate physiologic tooth movement and greater patient comfort. www.indiandentalacademy.com
  14. 14. Pseudoelasticity –stress-related behavior of Ni-Ti • The deflection in an austenitic archwire at oral temp. generates a local martensitic transformation and produce stress induced martensite-SIM. • SIM is unstable and undergoes reverse transformation as soon as stress is removed. • In clinical application SIM forms where the wire is tied to brackets on misaligned teeth so that the wire becomes pliable ,with seemingly permanent deformation. www.indiandentalacademy.com
  15. 15. Cu Ni-Ti…Advancing towards ideal archwire • Cu Ni-Ti alloy wire represents a major advancement in shape memory wires by reducing hysteresis and by providing precise transformation temperature at four different levels.www.indiandentalacademy.com
  16. 16. Role of Copper :- • Cu enhances the thermal reactive properties of Ni-Ti alloys thus providing equal loading (engaging) and unloading (tooth driving) forces. • Cu gives precise control of the transformation temperature. • Cu produces lubricants to the system and decreases friction.www.indiandentalacademy.com
  17. 17. Configuration of available Superelastic Ni-Ti and Heat-activated Ni-Ti Round Ni-Ti Rectangular & Square Ni-Ti www.indiandentalacademy.com
  18. 18. After Before www.indiandentalacademy.com
  19. 19. After Before www.indiandentalacademy.com
  20. 20. www.indiandentalacademy.com
  21. 21. www.indiandentalacademy.com
  22. 22. Recycling of Ni-Ti Recycling involves • Repeated exposure of the wire for several weeks or months to mechanical stresses and elements of the oral environment • Sterilization between uses www.indiandentalacademy.com
  23. 23. • Heat sterilization is the most reliable method - (Steam autoclaving at 1210 C,15-20psi for 20 min) • Chemical sterilization are corrosive &attack metals immersed in them (2% acidic Glutaraldehyde) www.indiandentalacademy.com
  24. 24. Advantages of Ni-Ti Fewer archwire changes Less chair side time Reduction in time required to accomplish rotations and leveling Less patient discomfort www.indiandentalacademy.com
  25. 25. Limitations to use of Ni-Ti Poor formability Fractures readily when bent over sharp edge and effects springback property Bending loops and stops in Ni-Ti is therefore not recommended.(cinch- backs can be obtained by flame – annealing the end of wire) www.indiandentalacademy.com
  26. 26. …and to conclude In contemporary practice no one archwire material meets all ideal requirements and the best results are obtained by using specific archwire material for specific purposeswww.indiandentalacademy.com
  27. 27. www.indiandentalacademy.com Thank you For more details please visit www.indiandentalacademy.com

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