1 P8 037: Introduction to Biomaterials 生醫材料導論 (Taught in English) 葉明龍 Phone: 63429 Email: [email protected]

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P8 037: P8 037: Introduction to BiomaterialsIntroduction to Biomaterials

生醫材料導論生醫材料導論 (Taught in English)(Taught in English)

葉明龍葉明龍 Phone: 63429 Phone: 63429

Email: [email protected]: [email protected]

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Alternative:Alternative:P8 017P8 017

Chemistry of BiomaterialsChemistry of Biomaterials生物材料化學生物材料化學

張憲彰張憲彰Wed. 5-7Wed. 5-7

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Time:Time: Mon. 6-8 (2:10-5:00 PM) Mon. 6-8 (2:10-5:00 PM) Office hours: Office hours: Wednesday, Thursday Wednesday, Thursday

10AM -12PM (Biomedical Engineering 10AM -12PM (Biomedical Engineering 5751A)5751A)

Grade: Grade: Homework: 30%Homework: 30%Tests: 50%Tests: 50%Final paper and Presentation: 20%Final paper and Presentation: 20%

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TextbooksTextbooks: :

Intend for Non-Materials backgroundIntend for Non-Materials backgroundFundamentals of Materials Science and Fundamentals of Materials Science and

Engineering (Chap 2-9)Engineering (Chap 2-9)

By: William D. Callister Jr.By: William D. Callister Jr.

Biomaterials Science: An Introduction tBiomaterials Science: An Introduction to Materials in Medicine (Chap 1, 2)o Materials in Medicine (Chap 1, 2)

By: Ruddy D. Ratner; Allan Hoffman; Frederick By: Ruddy D. Ratner; Allan Hoffman; Frederick Schoen and Jack LemonsSchoen and Jack Lemons

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Introductory book:Introductory book: 生物醫學材料王盈錦生物醫學材料王盈錦

References: References: 1. Biomaterials 1. Biomaterials

by Sujata Bhatby Sujata Bhat

2. Biomaterials: An Introduction 2. Biomaterials: An Introduction

by Joon Bu Parkby Joon Bu Park

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Students Self IntroductionStudents Self Introduction

1.1. Fill your name, email, phone, Institute, Fill your name, email, phone, Institute, Grade (Year) and AdvisorGrade (Year) and Advisor

2.2. Name, Institute, Grade (Year)Name, Institute, Grade (Year)

3.3. AdvisorAdvisor

4.4. Main focus of your labMain focus of your lab

5.5. Possible research directionPossible research direction

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Curriculum:Curriculum:

Week Content1. Opening statement: Introduction (Biomaterials Page 1-9)2. I. Materials Science and Engineering

Chap 2 Atomic Structure and Interatomic BondingChap 3. Structures of Metals and Ceramics

3. Chap 4. Polymer StructureChap 5 Imperfections in Solids

4. Chap 6. DiffusionChap 7. Mechanical Properties

5. Chap 8. Deformation and Strengthening MechanismsChap 9. Failure

6. Test I

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7. II. Biomaterials1.4 Surface properties and surface characterization1.5 Role of water in biomaterials

8. 2.2 Polymers9. 2.3 Silicone Biomaterials

2.4 Medical fibers and biotextiles10. 2.5 Hydorgels

2.6 Smart Polymers11. 2.7 Bioresorbable and Bioerodible Materials

2.8 Natural Materials12. 2.9 Metals

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13. 2.10 Ceramics, Glasses, and Glass-Ceramics14. 2.11 Pyrolytic Carbon

2.12 Composite15. 2.13 Nonfouling surfaces

2.14 Physicochemical Surface modification16. 2.15 Textured and Porous Materials

2.16 Surface-Immobilized Biomolecules17. Final presentation 18. Test II

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Biomaterials: Definition Biomaterials: Definition

(1987, Williams) A biomaterial is a (1987, Williams) A biomaterial is a nonviable nonviable materialmaterial used in a used in a medical devicemedical device, intended to , intended to interact with biological system.interact with biological system.

(Bhat) (Bhat) Nondrug materialNondrug material that can be used to that can be used to trtreateat, , enhance or replace any tissue, organenhance or replace any tissue, organ, or f, or function in a organism.unction in a organism.

(Bhat) (Bhat) Biological derived materialBiological derived material that is used f that is used for its structural rather than its biological properor its structural rather than its biological properties.ties.

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Definition:Definition:

(Merriam-Webster) Materials used for or (Merriam-Webster) Materials used for or suitable for used in suitable for used in prosthesesprostheses that that comes in direct contact with living comes in direct contact with living tissues. tissues.

Biocompatibility:Biocompatibility: ability of a material to ability of a material to perform with an appropriate host perform with an appropriate host response in a specific applicationresponse in a specific application

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IntroductionIntroduction Biomaterials used in these devices: Biomaterials used in these devices:

ophthalmology, ophthalmology, cardiology, cardiology, neuromuscular surgery, neuromuscular surgery, orthopedics and orthopedics and dentistrydentistry. .

All biomaterials in common; All biomaterials in common; they must have they must have intimate contact with patient’s tissueintimate contact with patient’s tissue or body or body

fluid, fluid, providing a providing a real physical interfacereal physical interface..

The search for new, more reliable devices require a The search for new, more reliable devices require a disciplined scientific approach to the subject.disciplined scientific approach to the subject.

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Introduction: Introduction: BiocompatibilityBiocompatibility

Good biocompatibilityGood biocompatibility is achieved when the is achieved when the material exists within a living body material exists within a living body without without adversely or significantly affecting it or being adversely or significantly affecting it or being affected by itaffected by it. .

The material should have The material should have adequateadequate mechanical mechanical strengthstrength, , chemical and physicalchemical and physical properties. properties.

Thus biomaterials must be compatible with body Thus biomaterials must be compatible with body tissues tissues mechanically, chemicallymechanically, chemically as well as as well as pharmacologicallypharmacologically. .

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IntroductionIntroduction

To research these materials the To research these materials the investigator need to have arrange of investigator need to have arrange of techniques for techniques for

1.1. materials productionmaterials production, ,

2.2. measurement of strength and surface measurement of strength and surface propertiesproperties and and

3.3. in vitroin vitro and and in vivoin vivo techniques for techniques for biocompatibility evaluation.biocompatibility evaluation.

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IntroductionIntroduction

The The functions of implantsfunctions of implants fall into one the fall into one the following categories: following categories: Load bearingLoad bearing or transmission or transmission artificial joint, fracture artificial joint, fracture

fixation fixation The control of The control of fluid flowfluid flow in order to stimulate normal in order to stimulate normal

physiological function or situationphysiological function or situation vascular graft, vascular graft, stent stent

Passive Passive space fillingspace filling either for either for cosmeticcosmetic reasons or reasons or functional reasonsfunctional reasons bone filling, skin bone filling, skin

Generation of Generation of electric stimulielectric stimuli and transmission of and transmission of light light and soundand sound.. electrode electrode

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Biomaterials: General perspectiveBiomaterials: General perspective

Biomaterials was also used to Biomaterials was also used to grow cells in culture, grow cells in culture, in apparatus for handling protein in in apparatus for handling protein in

laboratory, laboratory, devices to regulate fertility in cattle, devices to regulate fertility in cattle, in aquaculture of oyster, cell-silicon in aquaculture of oyster, cell-silicon

“biochip“biochip”. ”. Biomaterials are rarely used as simple Biomaterials are rarely used as simple

materials, integrated into devicesmaterials, integrated into devices (final (final fabricated, sterilized form)fabricated, sterilized form)

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Biomaterials science Biomaterials science The The physical and biologicalphysical and biological study of materials study of materials and their and their

interaction interaction with the with the biological environmentbiological environment. . TraditionallyTraditionally investigation: investigation:

biomaterials synthesis, optimization, characterization, biomaterials synthesis, optimization, characterization, testingtesting

the biology of host-material interactions. the biology of host-material interactions. Most biomaterials introduce a Most biomaterials introduce a non-specific, stereotyped non-specific, stereotyped

biological reaction.biological reaction.

Current effort:Current effort: toward the development of engineered surfacestoward the development of engineered surfaces that could that could

elicit rapid and highly precise reactions with cells and elicit rapid and highly precise reactions with cells and proteinsproteins, ,

tailored to a specific application.tailored to a specific application.

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BiocompatibilityBiocompatibility

Indeed, a Indeed, a complementary definitioncomplementary definition essential for understanding the essential for understanding the goal (i.e., goal (i.e., specific end applications ) of biomaterialsspecific end applications ) of biomaterials science is that of science is that of “biocompatibility”.“biocompatibility”.

"Biocompatibility” is the ability of "Biocompatibility” is the ability of a material a material to perform with an appropriate host to perform with an appropriate host responseresponse in a specific application in a specific application (Williams, 1987).(Williams, 1987).

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Examples of "appropriate host responses" Examples of "appropriate host responses" include include the resistance to blood clotting, the resistance to blood clotting, resistance to bacterial colonization, and resistance to bacterial colonization, and normal, uncomplicated healing. normal, uncomplicated healing.

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This This general concept of biocompatibilitygeneral concept of biocompatibility has been has been extendedextended recently in the broad recently in the broad approach called "tissue engineering" approach called "tissue engineering" careful selection of careful selection of cells, materials, and cells, materials, and

metabolic and biomechanical conditionsmetabolic and biomechanical conditions to to regenerate functional tissues.regenerate functional tissues.

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Classic Examples of Classic Examples of BiomaterialsBiomaterials

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Classic Examples: Table 1 Classic Examples: Table 1 (Ratner) (Ratner)

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Classic Examples: Table 1 Classic Examples: Table 1 (Ratner)(Ratner)

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Classic Examples: Table 1 Classic Examples: Table 1 (Ratner)(Ratner)

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Biomaterials and Biomaterials and health care markethealth care market

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Classic ExamplesClassic Examples Substitute Heart Substitute Heart

valvesvalves:: Heart valve Heart valve prostheses are fabricated prostheses are fabricated from from carbons, metals, carbons, metals, elastomers, fabricselastomers, fabrics and and natural (e.g. pig) valves and natural (e.g. pig) valves and other tissues chemically other tissues chemically pretreated to reduce their pretreated to reduce their immunologic reactivity and immunologic reactivity and enhance durability. enhance durability.

Problem: Problem: degeneration of degeneration of tissuetissue, mechanical failure, , mechanical failure, postoperative infection, and postoperative infection, and induction of blood clot. induction of blood clot.

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Classic ExamplesClassic Examples Artificial Hip JointArtificial Hip Joint: The : The

human hip joint is subjected to human hip joint is subjected to high mechanical stress and high mechanical stress and undergoes considerable undergoes considerable abuse. abuse.

Hip joints are fabricated from Hip joints are fabricated from specific specific high-strength alloy, high-strength alloy, ceramics, composites, and ceramics, composites, and ultrahigh molecular weight ultrahigh molecular weight polyethylene. polyethylene.

In most cases, good function In most cases, good function is restored, and even athletic is restored, and even athletic activities are possible. activities are possible.

After 10-15 years, the implant After 10-15 years, the implant may loosen, necessitating may loosen, necessitating another operation.another operation.

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Classic ExamplesClassic Examples

Dental implantDental implant: : Titanium implants, which Titanium implants, which form an artificial tooth form an artificial tooth root on which crown is root on which crown is affixed. affixed.

A special requirement of A special requirement of a material in this a material in this application is the ability application is the ability to form a to form a tight seal tight seal against bacterial against bacterial invasioninvasion where the where the implant traverses the implant traverses the gingival (gum). gingival (gum).

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Classic ExamplesClassic Examples

Intraocular LensesIntraocular Lenses:: Intraocular Lenses (IO Intraocular Lenses (IOLs) made by Ls) made by poly (methpoly (methyl methacrylate), siliconyl methacrylate), silicone elastomer,e elastomer, or other m or other materials are used to replaterials are used to replaced a natural lens whaced a natural lens when it become cloudy anen it become cloudy and cataractous. d cataractous.

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Characteristics of Biomaterials Characteristics of Biomaterials ScienceScience

MultidisciplinaryMultidisciplinaryMany diverse materialsMany diverse materialsDevelopment of biomaterials devicesDevelopment of biomaterials devicesMagnitude of the fieldMagnitude of the fieldSuccess and failureSuccess and failure

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Characteristics of Biomaterials Characteristics of Biomaterials Science: Science: MultidisciplinaryMultidisciplinary

More than any other field of contemporary More than any other field of contemporary technology, biomaterials science brings technology, biomaterials science brings together researchers from diverse together researchers from diverse backgrounds who must communicate clearly.backgrounds who must communicate clearly.

Figure 6 lists some of the Figure 6 lists some of the disciplines disciplines that are that are encountered in the progression from encountered in the progression from identifying the need for a biomaterialidentifying the need for a biomaterial or or device to its manufacture, sale, and device to its manufacture, sale, and implantationimplantation..

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Many Diverse Materials:Many Diverse Materials:

The biomaterials scientist will have an The biomaterials scientist will have an appreciation of appreciation of materials sciencematerials science. .

This may range from This may range from an impressive command of the an impressive command of the theorytheory and and practicepractice of the field demonstrated by the of the field demonstrated by the

professional materials scientistprofessional materials scientist to to a general a general understanding of the properties of understanding of the properties of

materialsmaterials that might be demonstrated by the that might be demonstrated by the physician or biologist investigator involved in physician or biologist investigator involved in biomaterials-related researchbiomaterials-related research..

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A wide range of materials is routinely A wide range of materials is routinely used and used and no one researcherno one researcher will be will be comfortable synthesizing and designing comfortable synthesizing and designing with with all these materialsall these materials. .

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Hard tissueHard tissue replacement biomaterials: metals, replacement biomaterials: metals, ceramics, used in orthopedic and dental ceramics, used in orthopedic and dental materials. materials.

Soft tissueSoft tissue replacement biomaterials: polymers, replacement biomaterials: polymers, cardiovascular and general plastic surgery cardiovascular and general plastic surgery materials. materials.

Some devices involved both soft and hard Some devices involved both soft and hard tissue. tissue.

There is need for a general understanding of all There is need for a general understanding of all class of materials.class of materials.

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Development of biomaterials Development of biomaterials devices: Fig 6.devices: Fig 6.

It provides a perspective on It provides a perspective on how how different disciplines work togetherdifferent disciplines work together, ,

starting from the identification of a need for starting from the identification of a need for a biomaterial through a biomaterial through

development, development, manufacture, manufacture, implantation, and implantation, and removal from the patient.removal from the patient.

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Characteristics of Biomaterials Characteristics of Biomaterials ScienceScience

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Magnitude of the field.Magnitude of the field.

Magnitude expresses both a magnitude Magnitude expresses both a magnitude of of need need and magnitude of and magnitude of a commercial a commercial market. market.

Needless to say, a conflict of interest can Needless to say, a conflict of interest can arise with pressure from both arise with pressure from both the the commercial quartercommercial quarter and from the and from the ethical ethical consideration. consideration.

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Success and FailureSuccess and Failure

Most biomaterials and medical devices perform Most biomaterials and medical devices perform satisfactorilysatisfactorily, , improving the quality of lifeimproving the quality of life for the for the recipient or saving lives. recipient or saving lives.

However, no manmade construct is perfect. However, no manmade construct is perfect. All manufactured devices have a failure rate. All manufactured devices have a failure rate. Also, all humans are Also, all humans are different different with differing with differing

genetics, gender, body chemistries, living genetics, gender, body chemistries, living environment, and degrees of physical activityenvironment, and degrees of physical activity. .

Furthermore, Furthermore, physiciansphysicians implant or use these implant or use these devices with varying devices with varying degrees of skilldegrees of skill. .

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Success and FailureSuccess and Failure The other side to the medical device success The other side to the medical device success

story is that there are story is that there are problems, compromises, problems, compromises, and complicationsand complications that occur with medical that occur with medical devices. devices.

Central issues for the biomaterials scientist, Central issues for the biomaterials scientist, manufacturer, patient, physician, and manufacturer, patient, physician, and attorney attorney are, are, (1) what represents good design, (1) what represents good design, (2) who should be responsible when devices perform " (2) who should be responsible when devices perform "

with an with an inappropriate host responseinappropriate host response," and ," and (3) what are the (3) what are the cost/risk or cost/benefit ratioscost/risk or cost/benefit ratios for the for the

implant or therapy?implant or therapy?

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Success and FailureSuccess and Failure Some examples may clarify these issues. Some examples may clarify these issues. Clearly, Clearly, heart valve diseaseheart valve disease is a serious medical is a serious medical

problem. Patients with diseased aortic heart problem. Patients with diseased aortic heart valves have a valves have a 50 % chance of dying within 3 50 % chance of dying within 3 years. years.

Surgical replacement of the diseased valve Surgical replacement of the diseased valve leads to an expected survival of leads to an expected survival of 10 years in 70 10 years in 70 % of the cases. % of the cases.

However, of these patients whose longevity and However, of these patients whose longevity and quality of life have clearly been enhanced, quality of life have clearly been enhanced, approximately 60 % will suffer a serious valve-approximately 60 % will suffer a serious valve-related complication within 10 years after the related complication within 10 years after the operation. operation.

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Subjects Integral to Subjects Integral to Biomaterials ScienceBiomaterials Science

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Subjects Integral to Subjects Integral to Biomaterials ScienceBiomaterials Science

ToxicologyToxicology BiocompatibilityBiocompatibility Functional tissue structure and pathobiologFunctional tissue structure and pathobiolog

yy HealingHealing Dependence on specific anatomical siteDependence on specific anatomical site Mechanical and Performance requirementsMechanical and Performance requirements:: Industrial involvementIndustrial involvement Ethics Ethics (Table 3)(Table 3) RegulationRegulation

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ToxicologyToxicology::

It deals with the substances that migrate It deals with the substances that migrate out of biomaterials. Ex: for polymers, out of biomaterials. Ex: for polymers, many low-molecular-weight “many low-molecular-weight “leachablesleachables” ” exhibit some level of physiologic activity exhibit some level of physiologic activity and cell toxicity. and cell toxicity.

It is reasonable to say that a biomaterial It is reasonable to say that a biomaterial should not give off anything from its should not give off anything from its massmass unless it is specifically designed to unless it is specifically designed to do so. do so.

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Biocompatibility:Biocompatibility: The The understanding and measurement of understanding and measurement of

biocompatibilitybiocompatibility is unique to biomaterials is unique to biomaterials science. science.

Unfortunately, we do Unfortunately, we do notnot have have precise precise definitionsdefinitions or or accurate measurementsaccurate measurements of of biocompatibility. biocompatibility.

It is defined in terms of It is defined in terms of performance or performance or success at a specific task.success at a specific task.

However, this However, this operational definition offers us operational definition offers us littlelittle to use in designing new or improved to use in designing new or improved vascular prostheses. vascular prostheses.

In fact, biocompatibility may have to be In fact, biocompatibility may have to be uniquely defined for each applicationuniquely defined for each application..

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Functional tissue structure and pFunctional tissue structure and pathobiologyathobiology

Biomaterials incorporated into medical devices Biomaterials incorporated into medical devices are implanted into tissues and organs. are implanted into tissues and organs.

Critical considerations to workers in the field.Critical considerations to workers in the field.1.1. The key The key principlesprinciples governing thegoverning the structurestructure of of

normal and abnormal cells, tissues, and normal and abnormal cells, tissues, and organs, organs,

2.2. the the techniques techniques by which the by which the structure and structure and functionfunction of normal and abnormal tissue are of normal and abnormal tissue are studied, and studied, and

3.3. the the fundamental mechanismsfundamental mechanisms of of disease disease processes processes

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HealingHealing Injury to tissue will Injury to tissue will stimulate the well define stimulate the well define

inflammatory reactioninflammatory reaction sequence that lead to sequence that lead to healing. healing.

When a When a foreign bodyforeign body is involved, the reaction is involved, the reaction sequence is referred to as “foreign body sequence is referred to as “foreign body reaction”. reaction”.

The The normal response of bodynormal response of body will be will be modulated because of the modulated because of the solid implantsolid implant. .

This reaction will This reaction will differ in intensity and durationdiffer in intensity and duration depending upon the anatomical sites involved. depending upon the anatomical sites involved.

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Dependence on specific Dependence on specific anatomical siteanatomical site::

Each site challenges the biomedical Each site challenges the biomedical device designer with device designer with special special requirements for geometry, size, requirements for geometry, size, mechanical properties, and bioreactionmechanical properties, and bioreaction..

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Mechanical and Performance Mechanical and Performance requirements:requirements:

Each biomaterial and device has imposed Each biomaterial and device has imposed upon in upon in mechanical and performance mechanical and performance requirementsrequirements that originate from the that originate from the physical physical (bulk) properties of the material(bulk) properties of the material. .

These requirements can be divided into three These requirements can be divided into three categories: categories:

mechanical performance, mechanical performance, mechanical durability, and mechanical durability, and physical properties (functional). physical properties (functional).

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Industrial involvementIndustrial involvement

The balance between the The balance between the desire to desire to alleviate loss of lifealleviate loss of life and suffering, and and suffering, and the corporate imperative to the corporate imperative to turn a profitturn a profit force us to look further afield force us to look further afield (out of the way)(out of the way) for guidance.for guidance.

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Ethics (1)Ethics (1)

Is Is the use of animalsthe use of animals justified? Specifically, is the justified? Specifically, is the experiment well designed and important so that experiment well designed and important so that the the data obtaineddata obtained will justify the will justify the suffering and suffering and sacrificesacrifice of the life of a living creature? of the life of a living creature?

How should research using humans be How should research using humans be conducted to minimize risk to the patient and conducted to minimize risk to the patient and offer a reasonable offer a reasonable risk-to-benefit ratiorisk-to-benefit ratio? How can ? How can we best ensure informed consent?we best ensure informed consent?

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Ethics (2)Ethics (2) Companies fund much biomaterials research and own Companies fund much biomaterials research and own

proprietary biomaterials. proprietary biomaterials. How can the How can the needs of the patientneeds of the patient be best balanced with be best balanced with

the the financial goalsfinancial goals of a company? of a company? Consider that someone must manufacture devices - - Consider that someone must manufacture devices - -

these would not be available if a company didn’t choose these would not be available if a company didn’t choose to manufacture them. to manufacture them.

Since researchers often stand to benefit financially from Since researchers often stand to benefit financially from a successful biomedical device and sometimes even a successful biomedical device and sometimes even have devices named after them, how can have devices named after them, how can investigator investigator biasbias be minimized in biomaterials research? be minimized in biomaterials research?

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Ethics (3) Ethics (3)

For life-sustaining devices, what is the For life-sustaining devices, what is the trade-off between trade-off between sustaining life and the sustaining life and the quality of lifequality of life with the device for the with the device for the Patient? Should the Patient be permitted Patient? Should the Patient be permitted to to "Pull the plug""Pull the plug" if the quality of life is not if the quality of life is not satisfactory? satisfactory?

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With so many With so many unanswered questionsunanswered questions about the basic science of biomaterials, do about the basic science of biomaterials, do government government regulatory agenciesregulatory agencies have have sufficient information to define adequate sufficient information to define adequate tests for materials and devices and to tests for materials and devices and to properly regulate biomaterials?properly regulate biomaterials?

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Should the government or other "third-Should the government or other "third-party payers" of medical costs party payers" of medical costs pay for the pay for the health care of patientshealth care of patients receiving devices receiving devices that have not yet been formally approved that have not yet been formally approved for general use by the FDA and other for general use by the FDA and other regulatory bodies? regulatory bodies?

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Should the CEO of a successful multimillion Should the CEO of a successful multimillion dollar company that is the dollar company that is the sole manufacturer a sole manufacturer a polymer materialpolymer material (that is a minor but crucial (that is a minor but crucial component of the sewing ring of nearly all heart component of the sewing ring of nearly all heart valves ) yield to the stockholders, demands that valves ) yield to the stockholders, demands that he/she terminate the sale of this material he/she terminate the sale of this material because of litigation concerning one model of because of litigation concerning one model of heart valve with a large cohort of failures? heart valve with a large cohort of failures?

The company sells 32 Pounds of this material The company sells 32 Pounds of this material annually, yielding revenue of approximately $40, annually, yielding revenue of approximately $40, 000?000?

Cohort: a group of individuals having a statistical factor (as age or class membership) in common in a demographic study

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Should an orthopedic appliance company Should an orthopedic appliance company manufacture two models of hip joint manufacture two models of hip joint prostheses: one with an expected prostheses: one with an expected "lifetime” of 20 years"lifetime” of 20 years ( for young, active ( for young, active recipients ) and another that recipients ) and another that costs one-costs one-fourthfourth as much with an expected lifetime of as much with an expected lifetime of 7 years ( for elderly individuals7 years ( for elderly individuals ), with the ), with the goal of saving resources so that more goal of saving resources so that more individuals can receive the appropriate individuals can receive the appropriate care?care?

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RegulationRegulation

To prevent inadequately tested devices and To prevent inadequately tested devices and materials from coming on the market, and to materials from coming on the market, and to screen out individuals clearly unqualified to screen out individuals clearly unqualified to produce biomaterial, a complex national produce biomaterial, a complex national regulatory system has been erected by the regulatory system has been erected by the United States government through the United States government through the Food Food and Drug Administration (FDA). and Drug Administration (FDA).

Through the Through the International Standards International Standards Organization (ISO),Organization (ISO), international regulatory international regulatory standards have been developed for the world standards have been developed for the world community. community.

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The The cost to meet the standardscost to meet the standards and to and to demonstrate compliance with material, demonstrate compliance with material, biological, and clinical are enormous. biological, and clinical are enormous.

Introducing a new biomedical device to the Introducing a new biomedical device to the market require a regulatory investment of market require a regulatory investment of many millions dollarsmany millions dollars. .

Are the regulations and standards Are the regulations and standards truly truly addressing the safety issue addressing the safety issue ??

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Is the Is the cost of regulationscost of regulations inflating the cost inflating the cost of health care and preventing improved of health care and preventing improved devices from those who need them?devices from those who need them?

Under this regulation topic, we see the Under this regulation topic, we see the interaction of all the players in the interaction of all the players in the biomaterials community: biomaterials community: government, government, industry, ethics and basic scienceindustry, ethics and basic science. .

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SummarySummary::

A A broad overview of the biomaterials broad overview of the biomaterials fieldfield. It provides a vantage point from . It provides a vantage point from which the reader can gain a perspective which the reader can gain a perspective to see how the to see how the sub-themes fit into the sub-themes fit into the larger wholelarger whole..

Biomaterials science may be the Biomaterials science may be the most most multidisciplinarymultidisciplinary all the sciences. all the sciences.

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SummarySummary::

Consequently, biomaterials scientists must Consequently, biomaterials scientists must mastmaster certain key material from many fieldser certain key material from many fields of of scienscience, technology, engineering, and medicinece, technology, engineering, and medicine in ord in order to be competent and conversant in this profeser to be competent and conversant in this profession. sion.

The reward for mastering this volume of material The reward for mastering this volume of material is immersion in an intellectually stimulating endeis immersion in an intellectually stimulating endeavor that avor that advances a new basic scienceadvances a new basic science of bioint of biointeraction and contributes to reducing human sufferaction and contributes to reducing human suffering.ering.

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Summary:Summary:

Basic definition of biomaterialsBasic definition of biomaterialsExample of biomaterials applicationExample of biomaterials applicationCharacteristics of biomaterials ScienceCharacteristics of biomaterials Science

MultidisciplinaryMultidisciplinaryMany diverse materialsMany diverse materialsDevelopment of biomaterials DevicesDevelopment of biomaterials DevicesMagnitude of the fieldMagnitude of the fieldSuccess and failureSuccess and failure

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Summary:Summary:

Subjects Integral to Biomaterials ScienceSubjects Integral to Biomaterials Science ToxicologyToxicology:: BiocompatibilityBiocompatibility Functional tissue structure and pathobiologyFunctional tissue structure and pathobiology Healing:Healing: Dependence on specific anatomical siteDependence on specific anatomical site Mechanical and Performance requirements:Mechanical and Performance requirements: Industrial involvementIndustrial involvement: : Ethics Ethics (Table 3)(Table 3) RegulationRegulation

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Home work I:Home work I: Due: Next week (9/20/2010)Due: Next week (9/20/2010)

I.I. Find an abstract from the least issue of “Biomaterials” Find an abstract from the least issue of “Biomaterials” and write your opinion about this paper. (100-300 and write your opinion about this paper. (100-300 words) (30%)words) (30%)

II.II. End Note:End Note: Following question I, copy the text of Following question I, copy the text of Introduction or Discussion with 10-20 references from Introduction or Discussion with 10-20 references from that paper and use End Note to cite these reference. that paper and use End Note to cite these reference. Build a End Note file for these reference. (45%)Build a End Note file for these reference. (45%)

III. III. What is your opinion about the ethical concerns What is your opinion about the ethical concerns related to biomaterials science? Please answer “one” related to biomaterials science? Please answer “one” of the issues from Table 3 (in page 8). Choose of the issues from Table 3 (in page 8). Choose anyone from that table. (25 %) (100-300 words)anyone from that table. (25 %) (100-300 words)

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Some helpful dictionary sites:Some helpful dictionary sites: http://www.m-w.org/http://www.m-w.org/ http://dictionary.reference.com/http://dictionary.reference.com/ http://dict.vghtpe.gov.tw/search.phphttp://dict.vghtpe.gov.tw/search.php http://tw.dictionary.yahoo.com/http://tw.dictionary.yahoo.com/ http://www.hk-doctor.com/html/dict.php ????http://www.hk-doctor.com/html/dict.php ???? http://www.google.com.tw/http://www.google.com.tw/

7171

To be continued…….To be continued…….

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Success and FailureSuccess and Failure Another example involves LVADs. Another example involves LVADs. A clinical trial called Randomized Evaluation of A clinical trial called Randomized Evaluation of

Mechanical Assistance for the Treatment of ConMechanical Assistance for the Treatment of Congestive Heart Failure (REMATCH) led to the follogestive Heart Failure (REMATCH) led to the following important statistics (Roseetal., 2001). wing important statistics (Roseetal., 2001).

Patients with an implanted Heartmate LVAD (ThPatients with an implanted Heartmate LVAD (Thoratec Laboratories) had a 52 % chance of survioratec Laboratories) had a 52 % chance of surviving for 1 year, compared with a 25 % survival raving for 1 year, compared with a 25 % survival rate for patients who took medication. te for patients who took medication.

Survival for 2 years in patients with the HeartmatSurvival for 2 years in patients with the Heartmate was 23 % versus 8 % in the medication group.e was 23 % versus 8 % in the medication group.

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Also, the LVAD enhanced the quality of life for thAlso, the LVAD enhanced the quality of life for the patients e patients 一一 they felt better, were less depressthey felt better, were less depressed, and were mobile. ed, and were mobile.

Importantly, patients participating in the REMATImportantly, patients participating in the REMATCH trial were not eligible for a heart transplant. CH trial were not eligible for a heart transplant.

In the cases of the heart valve and the LVAD, loIn the cases of the heart valve and the LVAD, long ng 一一 term clinical complications associated witterm clinical complications associated with imperfect performance of biomaterials do not ph imperfect performance of biomaterials do not preclude clinical success overall.reclude clinical success overall.

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These five characteristics of biomaterials These five characteristics of biomaterials science : (1)multidisciplinary, (2)multimaterial, science : (1)multidisciplinary, (2)multimaterial, (3)need-driven, (4)substantial market, and (3)need-driven, (4)substantial market, and (5)risk-benefit, flavor all aspects the field. (5)risk-benefit, flavor all aspects the field.

In addition, there are certain subjects that are In addition, there are certain subjects that are particularly prominent in our field and help particularly prominent in our field and help delineate biomaterials science as a unique delineate biomaterials science as a unique endeavor · Let us review a few of these.endeavor · Let us review a few of these.

to describe, portray, or set forth with accuracy or in detail

Documents

1 P8 037: Introduction to Biomaterials 生醫材料導論 (Taught in English) 葉明龍 Phone: 63429 Email: [email protected]