6/4/2010
Biomaterials
in Medical device design
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Dr J o sep h B u h a g ia r
B.Eng (Hons.)
PhD (Bham)
Department of Metallurgy and Materials
Engineering
University of Malta
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
What is a biomaterial?
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A biomaterial is a nonviable material used in a
medical device intended to interact with biological
systems (Williams, 1987)
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
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What is a biomaterial?
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“medical” removed from definition:
growing cells in culture
processing biomolecules for biotechnology
diagnostic gene arrays
aquaculture of oysters
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
What is a biomaterial?
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“nonviable” removed from definition:
tissue engineering
hybrid artificial organ applications
living cells that are used as materials
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
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What is a biocompatibility?
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“Biocompatibility” is the ability of a material to
perform with an appropriate host response in a
specific application (Williams, 1987)
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
What is a biocompatibility?
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“host response”:
resistance to blood clotting
resistance to bacterial colonization
normal (uncomplicated) healing
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
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What is a biocompatibility?
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“specific application”:
haemodialysis membrane (blood 3hrs)
urinary catheter (inserted for a week)
hip-joint replacement (life of a patient)
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
Biomaterial performance requirements
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Performance requirements :
mechanical performance
mechanical durability
physical properties
biocompatibility
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
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Biomaterial a multidisciplinary endeavour
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Medicine
Biology
REQUIREMENTS
Chemistry
Manufacturing
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
Family of biomaterials
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Ceramic
Al2O3
ZrO2, TiO2
Composite
Metallic
Polymeric
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
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Metallic biomaterials
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Titanium Alloys
Shape Memory Alloys
Cobalt- Chromium
Austenitic Stainless Steels
Zirconium Alloys
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
Ceramic biomaterials
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Alumina (Al2O3)
Zirconia (ZrO2)
Calcium Phosphate
Hydroxyapatite (HA)
Bioactive Glasses
Glass-Ceramics
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
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Ceramic biomaterials
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Toxic
surrounding material dies
Nontoxic and biologically inactive (inert)
fibrous tissue of variable thickness forms
Nontoxic and biologically active (bioactive)
interfacial bond forms
Nontoxic and dissolves
surrounding tissue replaces it
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
Polymeric biomaterials
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Ultra High Molecular Weight Polyethylene
(UHMWPE)
Polymethyl-methacrylate (PMMA)
Silicone Biomaterials
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
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Nanotechnology in biomaterials
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Silver Antimicrobial protection
Biotextiles and dressings
Handles in hospitals
Medical devices
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
Degradation of biomaterials
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Pitting and crevice corrosion
Fretting and corrosion-wear
Fatigue
Deformation
Release of toxic elements
Nickel
Chromium (VI)
Cobalt
Vanadium
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
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Surface engineering of biomaterials
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Coat or alloy the surface for:
hardness
corrosion-wear resistance
fatigue resistance
corrosion properties
biocompatibility
osseointegration
hydrophilicity
antibacterial properties
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
Research in biomaterials (DMME)
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Surface engineering of biomaterials
Medical grade austenitic stainless steels
Ni-Ti Shape memory alloys
Development of dental biomaterials
Dental cement in collaboration with Dr. J Camilleri
Degradation evaluation of biomaterials
Crevice Corrosion
Pitting Corrosion
Fretting-wear
Corrosion-wear
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
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Collaboration interests (DMME)
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Biocompatibility
In-vitro and in-vivo testing
Wet chemical analysis
Ni and Cr content in solution
Clinical studies
Analysis of implant retrieval
Design and manufacturing
Prototypes manufacture and mechanical testing
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
Surface nano analysis and characterisation
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Low Energy Electron Diffraction
Scanning Electron Microscope
Secondary Ion Mass Spectroscopy
X-Ray Photoelectron Spectroscopy
Auger Electron Spectroscopy
Scanning Tunnelling Microscope
Atomic Force Microscope
Time of Flight
Funding ERDF:
Setting up a material testing & rapid
prototyping R&D facility
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
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Confocal laser scanning microscope
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Biological Samples
High Resolution Image Requisition
True Spectral imaging
32 Channels of fluorescence
Gentle on living cells
Funding ERDF:
Setting up a material testing & rapid
prototyping R&D facility
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
Scanning Electron Microscope (SEM)
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Field Emission
Energy Dispersive Spectroscopy
(EDS)
Wave Dispersive Spectroscopy
(WDS)
Electron Backscattering Diffraction
(EBSD)
Funding ERDF:
Setting up a material testing & rapid
prototyping R&D facility
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
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Nano-indentation and hardness
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Nano Indentation:
Hardness Testing of thin films
Hot stage
Cold Stage (-30°C)
Liquid Cell
Impact testing
Scratch testing
Other hardness testing:
Macro-hardness
Vickers micro-hardness
Shore hardness
Funding ERDF:
Setting up a material testing & rapid
prototyping R&D facility
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
X-Ray Diffraction
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Phase determination
Stress Analysis
Thin film analysis
Hot Stage
Funding ERDF:
• Setting up a material testing & rapid
prototyping R&D facility
• 4th Italian Protocol
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
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Mechanical and corrosion testing
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Tensile Tester
Compression Tester
Rotary Fatigue Tester
Tribometer (pin-on-disc)
Impact tester
Potentiostat (corrosion)
Salt spray cabinet
Funding ERDF:
• Setting up a material testing & rapid
prototyping R&D facility
• 4th Italian Protocol
Biomedical Device Design & Manufacture in Malta - 1st June 2010, Dolmen, Qawra
Email: [email protected]
Tel:
2340 2439
Room: 107: Engineering Building
Biomedical Device Design & Manufacture
26in Malta - 1st June 2010, Dolmen, Qawra
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