INTRODUCTION TO
BIOMATERIALS
LECTURE 1
BME202-BIOMATERIALS
8/2/2021
NEU, ASSOC. PROF. DR. TERIN ADALI
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INTRODUCTION TO MATERIAL SCIENCE AND BIOMATERIALS
Properties and applications of materials (synthetic and
natural) that are used in contact with biological systems.
Material Science, is the discipline that study the nature of
materials;
In terms of their;
• Structure,
• Composition,
• Properties (structural, mechanical, physical, chemical,
biological),
General AIM;
• Understand the structure of material,
• Understand the relationship between structure
and properties of materials.
• Classify materials.
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NEU, ASSOC. PROF. DR. TERIN ADALI
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OBJECTIVES
To introduce the different materials & biomaterials used both in
Bioengineering, food & biomedical engineering, and provide
some fundamental properties of these materials, and indicate
how they are used.
OUTLINE
Introduction: *need for biomaterials, definition of
biocompatibility and introduce classes of
biomaterials.
****Material properties, Metals, Ceramics, Polymers.
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NEU, ASSOC. PROF. DR. TERIN ADALI
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MATERIALS & BIOMATERIALS COURSE
Interdisciplinary;
Medicine
Food
Biology
Chemistry
Materials Science
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NEU, ASSOC. PROF. DR. TERIN ADALI
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BIOMATERIAL
A biomaterial is a nonviable material used in a medical device,
intended to interact with biological systems (Williams, 1987).
BIOCOMPATIBILITY: Is the ability of a material to perform with an
appropriate host response in a specific applications (Williams,
1987)
Appropriate host responses: The resistance to blood clotting, resistance to bacterial colonization,
and normal, uncomplicated healing.
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NEU, ASSOC. PROF. DR. TERIN ADALI
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BIOMATERIALS;
Primarily used for bitechnology, food biotechnology,
medical bitechnology applications. (Integrated into
devices or implants)
Used to grow cells in culture.
To assay for blood proteins in the clinical laboratory.
In equipment for processing biomolecules for
biotechnological applications.
For implants to regulate fertility in cattle.
In diagnostic gene arrays.
In the aquaculture of ecosystems.
For investigational cell-silicon ‘biochips’.
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NEU, ASSOC. PROF. DR. TERIN ADALI
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Historical Development of Materials
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NEU, ASSOC. PROF. DR. TERIN ADALI
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ENGINEERING MATERIALS
METALS
IRON BASED
METALS
1- Welding Metals
2- Steels
2.08.2021
NON-METALS
OTHER
METALS
1- Light metals
(Al, Mg, Ti, Be)
2-Heavy Metals
(Cu, Ni, Zn, Pb)
Inorganic
materials
(Semi conductors,
Ceramics, Glasses)
Organic
Materials
(Polimers, skin,
wood)
YDÜ, MÜHENDISLIK FAKÜLTESI, DOÇ. DR. TERIN ADALI
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FOUR COMPONENTS OF MATERIAL SCIENCE AND
ENGINEERING DISCIPLINES
PROCESSES
STRUCTURE
PROPERTIES
PERFORMANS
PROCESSES: Processes, manufacturing,
SYNTHESIS: Naturally occured products by chemical or
biological processes.
STRUCTURE
: Structure of atoms and ions in the materials.
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YDÜ, MÜHENDISLIK FAKÜLTESI, DOÇ. DR. TERIN ADALI
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WHAT ARE BIOMATERIALS?
A biomaterial
 is a material used in a medical device, intended to interact with biological systems.
 is used to make devices to replace
a part of a function of the body in a
safe, reliable, economic, and
physiologically acceptable manner.
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NEU, ASSOC. PROF. DR. TERIN ADALI
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A haemodialysis' system; serving as an artificial kidney
requires materials that must function;
In contact with a patient’s blood.
Exhibit appropriate membrane permeability
Mass transport characterization.
It must employ mechanical and electronic systems to pump
blood and control flow rates.
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NEU, ASSOC. PROF. DR. TERIN ADALI
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NEU, ASSOC. PROF. DR. TERIN ADALI
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•
Pacemaker
BIOMATERIAL is any substance (other than a drug), natural or synthetic, that treats,
augments, or replaces any tissue, organ, and body function.
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NEU, ASSOC. PROF. DR. TERIN ADALI
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The need for biomaterials stems from an inability to
treat many diseases, injuries and conditions with
other therapies or procedures :




replacement of body part that has lost function (total hip, heart)
correct abnormalities (spinal rod)
improve function (pacemaker, stent)
assist in healing (structural, pharmaceutical effects: sutures, drug release)
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NEU, ASSOC. PROF. DR. TERIN ADALI
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EXAMPLES OF BIOMATERIALS APPLICATIONS
1.
SKELETAL SYSTEM APPLICATIONS
2.
CARDIOVASCULAR SYSTEM APPLICATIONS
3.
ARTIFICIAL ORGANS
4.
SENSES APPLICATIONS
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NEU, ASSOC. PROF. DR. TERIN ADALI
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1.
Skeletal system applications
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Applications
Types of Materials
Joint replacement (hip, knee)
Titanium, Ti-Al-V alloy, stainless
steel, polyetheylene
Bone plate for fracture,
fixation
Stainless steel, cobalt-chromium
alloy
Bone cement
Poly(methyl metacrylate)
Bone defect repair
Hydroxylapatite
Artificial tendon and ligament
Teflon, Dacron
Dental implant for tooth
fixation
Titanium, Ti-AliV alloy, stainless
steel, carbon
NEU, ASSOC. PROF. DR. TERIN ADALI
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2. Cardiovascular system
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APPLICATION
TYPES OF MATERIALS
Blood vessel prosthesis
Dacron, Teflon, polyurethane,
Heart valve
Reprocessed tissue, stainless
steel, carbon
Catheter
Silicon rubber, Teflon,
polyurethane
NEU, ASSOC. PROF. DR. TERIN ADALI
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3. Artificial Organs
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APPLICATIONS
TYPES OF MATERIALS
Artificial heart
Polyurethane
Skin repair template
Silicon-collagen composite
Artificial kidney (hemodializer)
Cellulose, polyacrylonitrile
Heart-lung machine
Silicon rubber
NEU, ASSOC. PROF. DR. TERIN ADALI
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4. Senses
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APPLICATIONS
TYPES OF MATERIALS
Cochlear replacement
Platinum electrodes
Intraocular lens
Poly(methymethacrylate),
silicon rubber, hydrıgel
Contact lens
Silicon-acrylate, hydrogel
Corneal Bandage
Collagen, hydrogel
NEU, ASSOC. PROF. DR. TERIN ADALI
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NEU, ASSOC. PROF. DR. TERIN ADALI
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Probability
of failure
Infection
Loosing
Fracture
Wear
0
5
10
15
Implant period (years)
A schematic illustration of probability of failure versus implant period
for hip joint replacements.
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NEU, ASSOC. PROF. DR. TERIN ADALI
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PERFOMANCE OF BIOMATERIALS
The perfomance of an implant after insertion can be considered in terms of
reliability.
e.g. Four major factors contributing to the failure of hip joint replacements.
1.
Fracture
2.
Wear
3.
Infection
4.
Lossing of implants
r=1-f where r is reliability, f is the probability of failure of a given system.
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NEU, ASSOC. PROF. DR. TERIN ADALI
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BACKGROUND
Historically, biomaterials consisted of materials common in the
laboratories of physicians, with little consideration of
material properties.
Early biomaterials:
 GOLD: Malleable, inert metal (does not oxidize); used in
dentistry by Chinese, Aztecs and Romans—dates 2000 years.
 IRON, BRASS: High strength metals; rejoin fractured femur
(1775).
 GLASS: Hard ceramic; used to replace eye (purely cosmetic).
 WOOD: Natural composite; high strength to weight; used for
limb prostheses and artificial teeth.
 BONE: Natural composite; uses: needles, decorative piercings.
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NEU, ASSOC. PROF. DR. TERIN ADALI
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HISTORY
• Important dates
– 1860's: Lister develops aseptic surgical technique
– early 1900's: Bone plates used to fix fractures
– 1930's: Introduction of stainless steel, cobalt chromium alloys
– 1938 : first total hip prosthesis (P. Wiles)
– 1940's: Polymers in medicine: PMMA bone repair; cellulose for
dialysis; nylon sutures
– 1952: Mechanical heart valve
– 1953: Dacron (polymer fiber) vascular grafts
– 1958: Cemented (PMMA) joint replacement
– 1960: first commercial heart valves
– 1970's: PEO (polyethyleneoxide) protein resistant thin film
coating
– 1976: FDA ammendment governing testing & production of
biomaterials /devices
– 1976: Artificial heart (W. Kolff, Prof. Emeritus U of U)
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NEU, ASSOC. PROF. DR. TERIN ADALI
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MOTIVATION
Improve quality of life..
Biomaterials is a 100 billion dolars + market, increasing at 57% /yr.
DEVICES CURRENTLY ON THE MARKET
8/2/2021
DEVICE
PATIENT
COST ($)
COST OF
ANNUAL
BIOMATERIAL REVENUE
($)
(USA) $
HEMODIALYER
18
6
110 M
PACEMAKER
6,000
75
6.75 M
HIP
3,000
100
0.5 M
Stent and
Catheter
3,000
30
1.75 M
NEU, ASSOC. PROF. DR. TERIN ADALI
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EXAMPLES OF USES OF BIOMATERIALS
Organ/Tissue Examples
heart
pacemaker, artificial valve, artificial heart
eye
contact lens, intraocular lens
ear
artificial stapes, cochlea implant
bone
bone plate, intramedullary rod, joint
prosthesis, bone cement, bone defect
repair
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kidney
dialysis machine
bladder
catheter and stent
muscle
sutures, muscle stimulator
circulation
artificial blood vessels
skin
burn dressings, artificial skin
endocrine
encapsulated pancreatic islet cells
NEU, ASSOC. PROF. DR. TERIN ADALI
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MATERIAL ATTRIBUTES FOR BIOMEDICAL
APPLICATIONS
Property
Desirables
Biocompatibility
Noncarcinogenic, nonpyrogenic,
nontoxic, nonallergenic, blood
compatible, non-inflammatory
Sterilizability
Not destroyed by typical sterilizing
techniques such as autoclaving, dry
heat, radiation, ethylene oxide
Physical characteristics Strength, elasticity, durability
Manufacturability
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Machinable, moldable, extrudable
NEU, ASSOC. PROF. DR. TERIN ADALI
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WHAT IS BIOCOMPATIBILITY?
Is the ability of a material to perform with an appropriate host
response in a specific applications (Williams, 1987).
Appropriate host responses;
• Resistance to blood clotting.
• Resistance to bacterial colonization
normal, uncomplicated healing.
Specific Applications;
• Haemodialysis membrane
• Urinary catheter
• Hip-joint replacement prosthesis.
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NEU, ASSOC. PROF. DR. TERIN ADALI
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BIOCOMPATIBILITY
1.
INTERACTION WITH –CELLS
--Muscles/Ligaments
--Fat
--Bones
--Organs
2. BIOMATERIALS
CHEMICAL, MECHANICAL, PHARMA-COLOGICAL, SURFACE: (Corrosion,
degradation, protein deposition, encapsulation, thrombus formation,
calcification, toxic leaching, embrittlement, cell lysis, systemic reaction.)
The success of a biomaterial or implant is highly dependent on three factors:
1.
The properties and biocompatibility of the implant.
2.
The health condition of the recipient
3.
The competency of the surgeon who implants and monitors its progress.
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NEU, ASSOC. PROF. DR. TERIN ADALI
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In general biocompatibility requirements are :
1. Acute systemic toxicity
2. Cytotoxicity
3. Hemolysis
4. Intravenous toxicity
5. Mutagenicity
6. Oral toxicity
7. Pyrogenicity
8. Sensitization
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NEU, ASSOC. PROF. DR. TERIN ADALI
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SURGICAL USES OF BIOMATERIALS
1.
PERMANENT IMPLANTS
Systems
Muscular skeletal system
Joint in upper (shoulder, elbow, finger)
and lower (hip, knee, ankle, toe)
extremities, permanently attached
artificial limb.
Cardiovascular system
heart, (valve, wall, pacemaker, entire
heart,) arteries, veins.
Respiratory system
Larynx, trachea, and bronchus, chest
wall, diaphragm, lungs
Digestive System
Tooth fillings, esophagus, bile ducts, liver
Genitouring system
Kidney, ureter, urethra, bladder
Nervous system
Dura, hydrocephalus shunt
Special senses
Corneal and lens prosthesis, ear cochlear
implant
Other soft tissues
Hernia repair sutures and mesh, tendons,
visceral adhesion
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Cosmetic
implants
NEU, ASSOC. PROF. DR. TERIN ADALI
Breast, eye, nose
,ear
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There is no general set of criteria, that if met, qualify a material
as being biocompatible.
The time scale over which the host is exposed to the material
or device must be considered.
MATERIAL
CONTACT TIME
Syringe needle
Tongue depressor
Contact lens
Bone screw/plate
Total hip replacement
Intraocular lens
1-2 s
10s
12hr-30 days
3-12 months
10-15 yrs.
30 + yrs
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NEU, ASSOC. PROF. DR. TERIN ADALI
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CHARACTERISTICS OF BIOMATERIALS
Multidisciplinary
Many Diverse Materials
Figure 1. Disciplines involved in biomaterials science and the
path from a need to a manufactured medical device
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NEU, ASSOC. PROF. DR. TERIN ADALI
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ACTION
1. Identify a need
IDEA
FACILITATOR
1. Physician/Dentist, Researcher,
Inventor
2. Device Design
2. Physician, Engineer
3. Materials Synthesis
3. Ceramicist, Metallurgist,
Polymer Chemist
5. Fabrication
6. Sterilization and
Packaging
7. Device Testing
IMPLEMENTATION
4. Materials Testing
4. Bioengineer, Mechanical
Engineer, Biochemist, Veterinarian
5. Engineer
6. Bioengineer, Industrial
designer
7. Bioengineer, physician/dentist
8. Regulatory Specialist, Agency,
Congress
8. Regulatory
9. Physician, Dentist, optometrist
9. Clinical Use
10. Pathologist, Bioengineer
10. Explant Analysis
PATIENT
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NEU, ASSOC. PROF. DR. TERIN ADALI
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CLASSES OF BIOMATERIALS
1. METALS; Stainless steel, cobalt alloys, titanium
alloys.
2. CERAMICS: Aluminium oxide, zirconia, calcium
phosphates.
3. POLYMERS: Silicones, poly(ethylene), poly(vinyl
chloride), polyurethanes, polylactides
NATURAL POLYMERS: Collagen, gelatin, elastin,
chitin, chitosan, silk, polysaccharides.
4. COMPOSITES:are those materials that contain two
or more constituent materials or phases, on
microscopic or macroscopic size scale.
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NEU, ASSOC. PROF. DR. TERIN ADALI
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MATERIAL PROPERTIES
OBJECTIVES
To introduce the fundamental mechanical and surface chemistry
properties of biomaterials.
OUTLINE
MECHANICAL PROPERTIES; Elasticity, viscoelasticity, brittle
fracture, fatique.
SURFACE CHEMISTRY
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NEU, ASSOC. PROF. DR. TERIN ADALI
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Materials testing
Mechanical properties
Toxicology
Bioreaction to the material protein interaction
Bioreaction to the material cell activation
Bioreaction to the material tissue reaction
Biostability mechanical
Biostability chemical
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