BIOMATERIALS
ENT 311/4
Course overview
Prepared by: Nur Farahiyah Binti Mohammad
Date: 7th July 2008
Email : farahiyah@unimap.edu.my
Course structure
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Course code: ENT 311/4
Lecturer: Miss Nur Farahiyah Mohammad
Mr Nashrul Fazli Mohd Nasir
Teaching Engineer: Miss Adilah Hashim
Course synopsis
Course outcome
12 topics
Lesson plan
2
Course assessment
Final Exam
:
 Test/Quiz
:
 Lab assessment :
 Assignment
:
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50%
10%
30%
10%
100%
3
List of text book and
references
Text book:
1.
Buddy D. Ratner, Allan S. Hoffman, Frederick J. Schoen & Jack E.
Lemons. Biomaterials Science: An Introduction to Materials in
Medicine. 2nd Ed., Elsevier Academic Press, 2004.
2.
Johnna S. Temenoff and Antonios G. Mikos. Biomaterials: The
Intersection of Biology and Materials Science. Prentice Hall, 2008.
Reference book:
1.
Joon B. Park & Joseph D. Bronzino. Biomaterials: Principles and
Applications, CRC Press, 2002.
2.
Joyce Y. Wong & Joseph D. Bronzino. Biomaterials, CRC Press,
2007.
3.
Joon B. Park & Roderic S. Lakes. Biomaterials: An Introduction, 2nd
Ed., Plenum Press, 1992.
4.
Sujata V. Bhat. Biomaterials, 2nd Ed., Alpha Science International
Ltd, 2005.
5.
Donglu Shi. Biomaterials and tissue engineering, Springer, 2004.
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BIOMATERIALS
ENT 311/4
Lecture 1: Introduction to Biomaterials
Prepared by: Nur Farahiyah Binti Mohammad
Date: 7th July 2008
Email : farahiyah@unimap.edu.my
Objective
Define biomaterials
 Describe biomaterial applications
 Define and describe biocompatibility
principle
 Explain factors contribute to the
performance of biomaterials in the
body.
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6
What is it biomaterial?
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A material intended to interface with
biological systems to evaluate, treat,
augment, or replace any tissue, organ or
function of the body (Williams, 1999).
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Any substance (other than drugs) or
combination of substance , synthetic or
natural origin, which can be used for any
period of time, as a whole or as a part of a
system which treats, augments, or replace
any tissue, organ or function of the body
(Williams, 1987).
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What is it biomaterial?
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A biomaterial is any material, natural or
man-made, that comprises whole or part of
a living structure or biomedical device
which performs, augments, or replaces a
natural function" (Wikipedia).
“A systemically and pharmacologically inert
substance designed for implantation within
or incorporation with living system” (The
Clemson University advisory Board for Biomaterials).
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Biomaterial
Application in
Human Body
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Biomaterials history
Year
Development
Late 18th–19th century
Various metal device to fix bone fracture: wire and pins
from Fe(Iron), Au (gold), Ag(silver), Pt (platinum)
1860-1870
Aseptic surgical units
(The use of biomaterials did not become practical until
the advent of an aseptic surgical technique develop by
Dr J. Lister.)
Early 1900
Bone plates were introduced to aid in fixation of long
bone fracture.
However, many of these early plates broke due
unsophisticated mechanical design;
-too thin
-Had stress concentrating corners.
-Corrode rapidly in the body
Introduction of stainless steel and cobalt chromium
alloys
10
Biomaterials history
Year
Development
1930s
Introduction of stainless steel and cobalt chromium alloys
1938
First total hip replacement prosthesis.
1940s
First used polymethyl methacrylate (PMMA) for corneal
implant and replacement of section of damaged skull bone.
(During World War II shattered perspex in pilots didn’t cause
problem.)
1946
First biomechanically designed femoral head replacement
prosthesis: first plastic (PMMA) used in joint replacement.
1950s
First successful blood vessel replacement
1960s
First commercial heart valve replacement
Cemented joint replacement
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Current status of the field
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Today, biomaterials represent a
significant portion of the healthcare
industry, with an estimated market
size of over $9 billion per year in the
United States.
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Current status of the field
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Cardiovascular area:
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approximately 100,00
replacement heart valves and
300,000 vascular graft
implanted per year in US.
Artificial joints replacements:
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Over 500,000 artificial joint
replacements, such as knee or
hip, are implanted yearly in
United States.
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Future Directions
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Starting 1960s-1970s
The first generation of biomaterials was
designed to be inert, or not reactive with
the body
 Decreasing the potential for negative
immune response to the implant.
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In 1990’s until now
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Materials designed to be bioactive,
interacting in positive manner with the
body to promote localized healing.
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Future Directions
Development of “smart” material which
can help guide the biological response
in the implant area.
 Design of injectable materials that can
applied locally and with minimal pain
to the patient.
 New set of nano-structured
biomaterials for nano-scale objects as
reinforcing agents.
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Application of Biomaterials
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Biomaterials that will be used may be considered from the
point of view of the problem area that is to be solved:
Problem Area
Examples
Replacement of diseased or
damaged part
Artificial hip joint, kidney dialysis machine
Assist in healing
Sutures, bone plates, and screws
Improve function
Cardiac pacemaker, intraocular lens,
cochlear implant
Correct functional abnormality
Cardiac pacemaker
Correct cosmetic problem
Breast implant, soft tissue augmentation,
chin augmentation
Aids to diagnosis
Probes, catheter
Aid to treatment
Catheters, drains
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Application of Biomaterials
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Biomaterials that will be used may be considered from the
point of view of the organ that will need to be replaced or
improve:
Organ
Heart
Heart
Cardiac pacemaker, artificial
heart valve, total artificial heart
Oxygenator machine
Contact lens, intraocular lens
Cochlear implant
Bone plate, screw
Kidney dialysis machine
Catheter and stent
Lung
Eye
Ear
Bone
Kidney
Bladder
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Type of Biomaterials
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Biomaterials are classified as:
Organic if contain carbon
 Inorganic if they do not.
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More specifically biomaterials fall into
one of three of materials:
Metals (inorganic material)
 Ceramics(inorganic material)
 Polymers (organic material)
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Type of Biomaterials
Biomaterials
Inorganic
Metals
Ceramics
Organic
Polymers
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Type of Biomaterials
Materials
Polymers
Nylon,
Polyethylene,
Silicone,
Teflon,
Dacron,
Acrylates,
PGA, PLA
Metals
(Titanium and its
alloys,
Co-Cr alloys,
stainless steel,
Gold)
Advantages
Disadvantages
Examples
Resilient,
Easy to
fabricate
Not Strong,
Deforms with
time,
may degrade
Sutures,
vascular graft,
hip socket,
intraocular
lenses
Strong,
Tough,
Ductile
May corrode,
Dense,
Difficult to make
Joint
replacement,
Bone plates and
screws,
Dental root
implant
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Type of Biomaterials
Materials
Ceramics
Aluminum oxide,
Calcium
phosphates,
Carbon
Composites
Carbon-carbon
Ceramic-polymer
Advantages
Disadvantages
Examples
Very
biocompatible,
Inert,
Strong in
compression
Brittle,
Not resilient,
Difficult to make
Dental implant,
Femoral head of
hip replacement,
Coating of
dental and
orthopedic
implants
Strong,
less stiff than
metals,
Strong in
compression
Difficult to make,
Weak in tension
Joint implants
Dental fillings
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Performance of
biomaterials
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The success of biomaterials in the body
depends on factors such as:
Material properties
 Design of the implants
 Biocompatibility of the materials
 Technique used by the surgeon
 Health and condition of the patient
 Patient activities
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The Concept of
Biocompatibility
Definition
of biocompatibility:
“Biocompatibility is the ability of a material to
perform with an appropriate host response in
a specific application” (William, 1987).
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The Concept of
Biocompatibility
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Biocompatibility characteristic:
Biocompatibility involves the acceptance
of an artificial implant by the surrounding
tissues and by the body as a whole.
 Biocompatible materials
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 Do
not irritate the surrounding structures
 Do not provoke an abnormal inflammatory
response
 Do not incite allergic or immunologic reactions
 Do not cause cancer
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The Concept of
Biocompatibility
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Biocompatible materials have adequate
mechanical properties.
Biocompatible materials have appropriate
optical properties (eye).
Biocompatible materials have appropriate
density.
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The End
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Supplementary slide
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Course synopsis
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This course is designed to provide a basic
knowledge of biomaterials and to provide
understanding of interactions between
physiological components and biomaterials.
Ranges of materials currently being utilized
for various biomedical applications and their
biocompatibility with references to the
biological responses and environments
available will be discussed.
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Course Outcomes
CO1:
Ability to describe the concept of biocompatibility and basic
concepts of materials used in medical application.
CO2:
Ability to explain and evaluate the biocompatibility of biomaterials
utilized as implants or contact devices with human tissues.
CO3:
Ability to explain and illustrate tissue reactions to biomaterials.
CO4:
Ability to select biomaterials that can be used for different medical
applications and explain the criteria that will lead to a successful
implants.
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Examples of Biomaterials
application
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Artificial hip joint
Needed because natural joint
wear out.
 Replacement hip joint are
implanted in more than 90 000
humans each year in US.
 Fabricated from titanium,
ceramics, composite, UHMWPE.
 After 10-15 years, the implant
may loose, require another
operation.
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Examples of Biomaterials
application
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Prosthetic Heart valve
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Fabricated from carbon, metal, elastomers,
fabrics, natural valves and tissue chemically pretreated.
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Show good performance as soon as
the valve is implanted but have some
problems:
Degeneration of tissue
 Mechanical failure
 Postoperative infection
 Induction of blood cloth
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Examples of Biomaterials
application
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Intraocular lenses (IOL)
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Used to replace a natural lense
when it become cloudy due to
cataract formation.
Fabricated of poly (methyl
methacrylate), silicone
elastomer, soft acrylic
polymers or hydrogels.
Complication: IOL stimulate
outgrowth cells from the
posterior lens capsule → cloud
the vision.
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Week
Content / Lecture Topic
Week 1
Introduction to Biomaterials
Week 2
Properties of biomaterials
Week 3
Polymeric Biomaterials
Week 4
Metallic Biomaterials
Week 5
Ceramic Biomaterials
Week 6
Tissue Reaction to Biomaterials
Week 7
Semester Break
Week 8
Tissue Reaction to Biomaterials
Mid Semester Test
Week 9
Biological Testing of Biomaterials
Week 10
Blood Contacting Implant
Week 11
Non-blood Interfacing Implant
Week 12
Hard Tissue Replacement: Internal Fixation and Joint
Replacement
Week 13
Special Break
Week 14
Hard Tissue Replacement: Internal Fixation and Joint
Replacement
Week 15
Tissue Engineering
Week 16
Scaffolds for Tissue Engineering
Assignment Presentation
Week 17
Revision week
Week 18-20
Final Examination
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