Orthodontics fine element method analysis.ppt

Orthodontics fine element method.ppt

2. NOBILITY IN THOUGHTS
BELIEF IN ACTION
AIMED IN THE RIGHT DIRECTION

3. INTRODUCTION TO THE FINITE ELEMENT
METHOD
----DR. CHETAN JAYADE
ASST. PROF.
DEPARTMENT OF ORTHODONTICS
S.D.M. DENTAL COLLEGE

4. My involvement with FEM
FEM Course at B.V.B, Hubli
FEM Course at MSRSAS, Bangalore

5. Why the need for orthodontists to know about
FEM?
An increase in the scope for research
A need for basic understanding about the engineering
areas of application.

6. SCOPE OF THE TALK
•An overview of FEA and it’s increasing role in
research
•Tounderstandthecapabilitiesandthelimitations
•Theroleofaclinicianinaresearchstudyinvolving
FEA
•StudiesinvariousbranchesofMedicineand
dentistryinvolvingFEA

7. SCOPE OF THE TALK
•UsageofFEAinOrthodontics
•SourcesofunderstandingFEA
•AnintroductiontoRapidPrototyping
•UsesofRapidPrototypinginDentistry

8. BIOMEDICAL ENGINEERING
An amalgamation of the medical and
engineering specialties
--Thehumangenomeproject
--CAD/CAM and other computerised
applicationareas

9. BIOMEDICAL ENGINEERING
Basic Research Clinical
Combination

10. BASIC RESEARCH
Experimental
Numerical Analytical
---FEA
---NON-FEA

11. WHAT IS FEA?
It is a means of discretizing a continuous structure
into sub-domains called Finite Elements.

12. WHAT IS FEA?
Essentiallyanattemptatsimulatingaphysical
objectandanalysingit’sbehaviourwhen
subjectedtovariouscircumstances

13. WHY FEA?
•Accuracy
•Reproducibility
•Nousageofmaterials
•Generationofintra-materialresults

14. FINITE ELEMENT ANALYSIS(FEA)
Termed by Clough in 1960
Gained popularity in the civil and the
Aerospace industry

15. FINITE ELEMENT ANALYSIS(FEA)
First introduced to the dental arena in the 1970’s
Growth model documented by MOSS in 1980.

16. FINITE ELEMENT ANALYSIS(FEA)
Current upsurge in interest due to
a)Potential of applicability
b)Desktop management

17. FINITE ELEMENT ANALYSIS(FEA)
Basic steps---
a)Pre-processing
b)Processing
c)Post-processing

18. FINITE ELEMENT ANALYSIS(FEA)
Pre-Processingbasicallyinvolvesmodellingof
thestructurebeingstudied.
Probably the most crucial step.

19. FINITE ELEMENT ANALYSIS(FEA)
Pre-Processing---Newerpossibilitiesof
modellingofcomplexstructures
a)3-DCTscanning
b)3-DLaserscanner
c)Voxelmodelling

20. FINITE ELEMENT ANALYSIS(FEA)
In Pre-processing, the structure being studied
is discretised into smaller units termed the
elements.
Each element is free to get displaced in all the
three planes of space.

22. FINITE ELEMENT ANALYSIS(FEA)
The element co-ordinates (x,y,z) can be either
a)Global Co-ordinate system or
b)The Local Co-ordinate system

23. FINITE ELEMENT ANALYSIS(FEA)
Variouscategoriesofelementsexist.
Examplesare
---Shellelement
---Beamelement
---Trusselementetc.

24. FINITE ELEMENT ANALYSIS(FEA)
EXAMPLES OF ELEMENTS

25. FINITE ELEMENT ANALYSIS(FEA)
These elements are connected at certain points
termed ‘Nodes’.
The joining of elements into nodes and eliminating
duplicate nodes is termed as “Meshing”

26. FINITE ELEMENT ANALYSIS(FEA)
The mesh size is a crucial determinant of the
accuracy of the result.
However, it is inversely related to the time involved
in the analysis.

27. FINITE ELEMENT ANALYSIS(FEA)
The meshed model is now a free floating body. To
simulate the exact structure, the material
properties are assigned and boundary
conditions enforced.

28. FINITE ELEMENT ANALYSIS(FEA)
Material properties : The minimum properties to be
assigned are a) The Modulus of elasticity and
b)Poisson’s ratio.

29. FINITE ELEMENT ANALYSIS(FEA)
Material properties : Modulus of elasticity(Young’s
modulus)refers to the stiffness of the material
within it’s elastic range.
E = Stress
------------
Strain

30. FINITE ELEMENT ANALYSIS(FEA)
Modulus of elasticity of dental structures are :
a)Enamel ---65 GPa
b)Dentin --15 GPa
c)Alveolar bone –10 GPa
d)Periodontal ligament –0.05 GPa

31. FINITE ELEMENT ANALYSIS(FEA)
Material properties : Poisson’s ratio denotes the
strain imposed on the material relative to the
axis of the load applied.
P = Strain perp. to the force
------------------------------------
Strain parallel to the force

32. FINITE ELEMENT ANALYSIS(FEA)
Poisson’s ratio for dental structures are:
a) Enamel --0.32
b) Dentin --0.28
c) Alveolar bone –-0.33
d) Periodontal ligament--0.3

33. FINITE ELEMENT ANALYSIS (FEA)
After assigning the material properties, the material
is constrained identical to the real situation.
The freedom of the body to be displaced is termed
as the “degrees of freedom”.
Each element has six degrees of freedom.

34. FINITE ELEMENT ANALYSIS (FEA)
The final step in Pre-processing is the application
of loads. These can be either force or moments
and be directed at any node in all the three
planes of space.

36. FINITE ELEMENT ANALYSIS(FEA)
WhatDoesTheComputerDoDuringThe
Processing?
a)Solvingofdifferentialequations.
b)Assemblageintomatrices
c)Summationofthematrixequations

37. FINITE ELEMENT ANALYSIS(FEA)
Theequationforthesimplestlinearstatic
analysisisrepresentedas:
[F]={K}{u}
The non-linear analysis is solved usually by what
is termed as the “Newton-Raphson method”

38. FINITE ELEMENT ANALYSIS(FEA)
Post-Processing--
a)Graphicaloutput
b)Numericaloutput
c)Animatedoutput

39. FINITE ELEMENT ANALYSIS(FEA)
Post-Processing--
a)Graphicaloutput
b)Numericaloutput
c)Animatedoutput

41. ROLE OF A MEDICAL OR A DENTAL
PROFESSIONAL DURING A RESEARCH
WORK INVOLVING FEA
•Planningafeasiblestudy
•Softwaretobeused
•TypeofModel–2-Dor3-D
•Typeofanalysis

42. ROLE OF A MEDICAL OR A DENTAL
PROFESSIONAL DURING A RESEARCH
WORK INVOLVING FEA
Software to be used
•Accuracy
•Analysismodules
•Mainframecapabilities

45. AREAS OF APPLICATIONS
BIOMECHANICAL MECHANICAL
Orthodontics
Prosthodontics
Oral Surgery
Periodontics

46. AREAS OF APPLICATIONS
ORTHODONTIC USAGE
Alternativetocephalometry
Growthassessment
Stresspatterngeneration

47. AREAS OF APPLICATIONS
ORTHODONTIC USAGE
•Limitationsofconventionalcephalometryin
establishingtheexactareasofgrowth.
•AdvantagesofFEMinGrowthstudies

48. AREAS OF APPLICATIONS
ORTHODONTIC USAGE
•MelvinMossusedtheconceptofGrowth
tensors.
•Tensors,althoughbeingabstractentities,are
abletopinpointthelocalgrowth
extensions(strains)

49. CONCEPT OF GROWTH TENSORS

50. CONCEPT OF GROWTH TENSORS

51. AREAS OF APPLICATIONS
ORTHODONTIC USAGE
Stresspatterngeneration---
Nasomaxillaryregion
Mandibleandcondyle
Dento-alveolar
Attachmentsandothermaterials

52. AREAS OF APPLICATIONS
ORTHODONTIC USAGE
Stresspatterngeneration---
Nasomaxillaryregion

53. MODELLING OF THE MANDIBLE

54. ANALYSIS OF THE MANDIBLE

55. MODELLING OF HUMAN TEETH

56. MODELLING OF HUMAN TEETH

57. MODELLING OF HUMAN TEETH
MODELLING OF HUMAN TEETH

58. MODELLING OF HUMAN TEETH

59. MODELLING OF HUMAN TEETH

60. LOSS OF ATTACHMENT AND IT’S RELATION TO
THE M/F RATIOS

61. RELEVANCE OF USING TPA AS A SOURCE OF
ANCHORAGE

62. MODELLING OF ORTHODONTIC
BRACKETS

63. ANALYSIS OF STRESSES IN ORTHODONTIC
BRACKETS

64. ANALYSIS OF STRESSES IN ORTHODONTIC
BRACKETS AND ADHESIVES

65. A MODELLED STANDARD LOOP
F
R

66. DISPLACED SHAPE OF THE LOOP

67. T Loop and L loop with angulated legs

68. T Loop and L loop with angulated legs

69. A NEW FINDING

70. AREAS OF APPLICATIONS
PROSTHODONTIC USAGE
Stresspatterngeneration---
Edentulousjaws
Completedentures
Over-dentures
CrownsandFixedpartialdentures
Implants

71. STRESS ANALYSIS OF A CAST
RESTORATION

72. MODELLING OF AN IMPLANT IN THE
MANDIBLE

73. ANALYSIS OF THE IMPLANT

74. AREAS OF APPLICATIONS
ORAL AND MAXILLOFACIAL SURGERY
Surgicalstressesgenerated
StressesintheTMJ
Distractionosteogenesisstresses

75. MODELLING OF THE HUMAN TMJ

76. THE MODELLED TMJ

77. ANALYSIS OF THE TMJ-NORMAL MOVEMENTS

78. ANALYSIS OF THE TMJ -ENFORCED MOVEMENTS

79. AREAS OF APPLICATIONS
PERIODONTICS
Stressesintheperiodontium
Changesduetolossofbonesupport
Designingoforalresonators

80. ANALYSIS OF RESONATORS

81. USES OF FEA IN PALEONTOLOGY
--A MODELLED DINOSAUR CRANIUM

82. SOURCES OF DATA
INTERNET–www.femur.wpi.edu
www.anamedic.com
www.feainfo.com
TEXTS:-Chandrupatlaet.al
LakshminarayanH.V
ChampionJr.

83. RAPID PROTOTYPING
This refers to the process of production of
any physical object scanned via special
devices.

84. RAPID PROTOTYPING
USES:
a)Instrumentdesigning
b)Maxillofacialsurgery
c)Implantology

85. RAPID PROTOTYPING
Outputgeneration
a)3-Dprinting
b)Stereolithography
c)Vacuumcasting
Facility of Rapid Prototyping available at the
IISC,Bangalore

86. USES OF RAPID PROTOTYPING
--CRANIOFACIAL DEFECTS

87. USES OF RAPID PROTOTYPING

88. APPLICATIONS OF RAPID PROTOTYPING

89. APPLICATIONS OF RAPID PROTOTYPING

90. CONCLUSION
TheinteractionofDentalandEngineering
fieldsisatanewhelm;wehavetriedto
initiateafruitfultogetherness.

91. THANK YOU