Bio Materials
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Biomaterials Biomaterials
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Tentang bagaimana suatu bahan bisa dijadikan material yang akan digunakan untuk tubuh manusia
Transcript of Bio Materials
BiomaterialsBiomaterials
DefiniDefinisisi
BBiomaterial merupakan bahan iomaterial merupakan bahan nonviable digunakan dalam nonviable digunakan dalam perangkat medis, dimaksudkan perangkat medis, dimaksudkan untuk berinteraksi dengan sistem untuk berinteraksi dengan sistem biologi biologi
Karakteristik Karakteristik BiomaterialBiomaterial
Syarat fisisSyarat fisis Material KerasMaterial Keras.. Material lenturMaterial lentur..
Syarat kimiawiSyarat kimiawi Harus tidak bereaksi dengan Harus tidak bereaksi dengan
sebarang jaringan di dalam tubuh.sebarang jaringan di dalam tubuh. Harus tidak beracun di tubuh.Harus tidak beracun di tubuh. Untuk pengganti jangka panjang Untuk pengganti jangka panjang
tidak boleh bersifat tidak boleh bersifat biodegradable.biodegradable.
SejarahSejarah Lebih dari 2000 tahun yang lalu, Lebih dari 2000 tahun yang lalu,
bangsa bangsa RomaRomawiwi, Cina, , Cina, mengmenggunakan gunakan emas emas untukuntuk implantimplant gigi. gigi.
Dalam perjalanannyaDalam perjalanannya, , bahan implant bahan implant sintetis mulai tersedia.sintetis mulai tersedia.
1937 Poly(methyl methacrylate) 1937 Poly(methyl methacrylate) (PMMA) (PMMA) diperkenalkan dalam diperkenalkan dalam dentistry.dentistry.
1958, Dacron 1958, Dacron mulai digunakan untuk mulai digunakan untuk arterial prosthetic.arterial prosthetic.
SejarahSejarah ......
1960 Charnley 1960 Charnley menggunakanmenggunakan PMMA, PMMA, ultrahigh-molecular-weight ultrahigh-molecular-weight polyethylen, polyethylen, dan dan stainless stestainless steeel l untuk untuk pengganti sendi/ tulang pengganti sendi/ tulang pinggulpinggul. .
Akhir Akhir 1960 – 1960 – awal awal 19701970 biomaterial biomaterial padatanpadatan
1975 1975 Asosiasi biomaterial dibentuk. Asosiasi biomaterial dibentuk.
Metals
Semiconductor Materials
Ceramics
Polymers
Synthetic BIOMATERIALS
Orthopedic screws/fixation
Dental Implants Dental Implants
Heart valves
Bone replacements
BiosensorsImplantable Microelectrodes
Skin/cartilageDrug Delivery Devices
Ocular implants
Biomaterial ScienceBiomaterial Science
GenerasipertamaGenerasipertama Biomaterial Biomaterial
Ditentukan Ditentukan hanya hanya oleh dokter .oleh dokter . Kebanyakan keberhasilan secara Kebanyakan keberhasilan secara
kebetulan , tidak dengan kebetulan , tidak dengan design.design.
Second Generation of Second Generation of BiomaterialsBiomaterials
Developed through collaborations Developed through collaborations of physicians and engineers. of physicians and engineers.
Engineered implants using common Engineered implants using common and borrowed materials.and borrowed materials.
Built on first generation Built on first generation experiences.experiences.
Used advances in materials science Used advances in materials science (from other fields).(from other fields).
Third generation implantsThird generation implants
Bioengineered implants using Bioengineered implants using bioengineered materials.bioengineered materials.
Few examples on the market.Few examples on the market. Some modified and new polymeric Some modified and new polymeric
devices.devices. Many under development.Many under development.
Examples of Biomaterial Examples of Biomaterial ApplicationsApplications
Heart ValveHeart Valve Artificial TissueArtificial Tissue Dental ImplantsDental Implants Intraocular LensesIntraocular Lenses Vascular GraftsVascular Grafts Hip ReplacementsHip Replacements
Heart ValveHeart Valve
Fabricated from carbons, metals, Fabricated from carbons, metals, elastomers, fabrics, and natural elastomers, fabrics, and natural valves.valves.
Must Must NOTNOT React With Chemicals in React With Chemicals in Body.Body.
Attached By Polyester Mesh.Attached By Polyester Mesh. Tissue Growth Facilitated By Polar Tissue Growth Facilitated By Polar
Oxygen-Containing Groups. Oxygen-Containing Groups.
Heart ValveHeart Valve Almost as soon as valve implanted Almost as soon as valve implanted
cardiac function is restored to near cardiac function is restored to near normal.normal.
Bileaflet tilting disk heart valve Bileaflet tilting disk heart valve used most widely.used most widely.
More than 45,000 replacement More than 45,000 replacement valves implanted every year in the valves implanted every year in the United States. United States.
Bileaflet Heart ValvesBileaflet Heart Valves
Problems with Heart Problems with Heart Valve’sValve’s
Degeneration of Tissue.Degeneration of Tissue. Mechanical Failure.Mechanical Failure. Postoperative infection.Postoperative infection. Induction of blood clots.Induction of blood clots.
Artificial TissueArtificial Tissue
BiodegradableBiodegradable Polymer Result Polymer Result
of Condensation of Condensation of Lactic Acid of Lactic Acid and Glycolyic and Glycolyic AcidAcid
Small titanium fixture that serves as the replacement for the root portion of a missing natural tooth.
Implant is placed in the bone of the upper or lower jaw and allowed to bond with the bone.
Most dental implants are: pure titanium screw-shaped cylinders that act as roots for crowns and bridges, or as supports for dentures.
Dental ImplantsDental Implants
Dental ImplantsDental Implants
Capable of bonding to bone, a phenomenon known as "osseointegration”.
Bio-inert, there is no reaction in tissue and no rejection or allergic reactions.
Dental ImplantsDental Implants
Intraocular LensesIntraocular Lenses
Made of PMM, silicone elastomer, and Made of PMM, silicone elastomer, and other materials.other materials.
By age 75 more than 50% of By age 75 more than 50% of population suffers from cataracts.population suffers from cataracts.
1.4 million implantations in the United 1.4 million implantations in the United States yearly.States yearly.
Good vision is generally restored Good vision is generally restored almost immediately after lens is almost immediately after lens is inserted. inserted.
Intraocular LensesIntraocular Lenses Implantation often performed on Implantation often performed on
outpatient basis.outpatient basis.
Vascular GraftsVascular Grafts
Must Be Flexible.Must Be Flexible. Designed With Designed With
Open Porous Open Porous Structure.Structure.
Often Recognized Often Recognized By Body As By Body As Foreign.Foreign.
Hip-ReplacementsHip-Replacements
Most Common Medical Practice Using Most Common Medical Practice Using Biomaterials.Biomaterials.
Corrosion Resistant high-strength Corrosion Resistant high-strength Metal Alloys.Metal Alloys.
Very High Molecular Weight Polymers.Very High Molecular Weight Polymers. Thermoset Plastics.Thermoset Plastics.
Some hip replacements ambulatory Some hip replacements ambulatory function restored within days after function restored within days after surgery.surgery.
Others require an extensive healing Others require an extensive healing period for attachment between bone period for attachment between bone and the implant.and the implant.
Most cases good function restored.Most cases good function restored. After 10-15 years, implant loosens After 10-15 years, implant loosens
requiring another operation.requiring another operation.
Hip-ReplacementsHip-Replacements
Hip-ReplacementsHip-Replacements
Vascular GraftsVascular Grafts Achieve and maintain homeostasis.Achieve and maintain homeostasis. Porous.Porous. Permeable.Permeable. Good structure retention.Good structure retention. Adequate burst strength.Adequate burst strength. High fatigue resistance.High fatigue resistance. Low thrombogenecity.Low thrombogenecity. Good handling properties.Good handling properties. Biostable.Biostable.
Vascular GraftsVascular Grafts Braids, weaves, and knits.Braids, weaves, and knits.
PorosityPorosity PermeabilityPermeability Thickness Thickness Burst strengthBurst strength Kink resistanceKink resistance Suture retentionSuture retention Wall thicknessWall thickness Tensile propertiesTensile properties Ravel resistance Ravel resistance
Vascular Grafts Vascular Grafts PermeabilityPermeability
BraidsBraids 350 to 2500 ml cm350 to 2500 ml cm22/min /min
KnitsKnits Loosely Woven KnitsLoosely Woven Knits
1200 to 2000 ml cm1200 to 2000 ml cm22/min /min Tightly Woven Knits Tightly Woven Knits
2000 to 5000 ml cm2000 to 5000 ml cm22/min /min WeavesWeaves
Below 800 ml cmBelow 800 ml cm22/min /min
Knit GraftsKnit Grafts
Filtration and FlowFiltration and Flow µ viscosity of µ viscosity of
fluidfluid t thickness of t thickness of
membranemembrane V velocity of fluidV velocity of fluid ΔΔp pressure drop p pressure drop
across across membranemembrane
ptvB
Void Content Kozeny-Void Content Kozeny-Carmen EquationCarmen Equation
KKo o is the Kozeny constant.is the Kozeny constant. SSo o is the shape factor.is the shape factor. ΦΦ is the porosity. is the porosity.
2
3
2 11
ooSK
B
2
3
2 11
ooSK
B
Shape FactorShape Factor
VolumeaSurfaceAreSo
Biomaterials: An Biomaterials: An ExampleExample
Biomechanics of Artificial Biomechanics of Artificial Joints Joints
Normal versus Arthritic Normal versus Arthritic HipHip
Sir John Charnely: 1960's, fundamental principles of the artificial hip
Frank Gunston: 1969, developed one of the first artificial knee joints.
Hip replacements done in the world per year: between 500,000 and 1 million.
Number of knee replacements done in the world per year: between 250,000 and 500,000.
Of all the factors leading to total hip replacement, osteoarthritis is the most common, accounting for 65% of all total hips.
Normal versus Arthritic Normal versus Arthritic HipHip
Normal Hip: note the space between the femur and
acetabulum, due to cartilage
Arthritic Hip: No space visible in joint, as
cartilage is missing
Two design issues in Two design issues in attaching materials to boneattaching materials to bone
1)1) the geometric and material the geometric and material design of the articulating design of the articulating surfacessurfaces
2)2) design of the interface between design of the interface between the artificial joint and the the artificial joint and the surrounding bone. surrounding bone.
using a Polymethylmethacrylate (PMMA) cement to adhere the
metal to the bone
using a porous metal surface to create a bone
ingrowth interface
Two attachment methodsTwo attachment methods
the acetabulum and the proximal femur have been replaced. The
femoral side is completely metal. The acetabular side is composed
of the polyethylene bearing surface
Overview of femoral Overview of femoral replacementreplacement
The two materials are bonded and equal force is
applied to both
Load transfer in Composite Load transfer in Composite materialsmaterials
Comparison: Modului of Comparison: Modului of ElasticityElasticity
Modulus of elasticity of different implant materials and bone (in GPa)
Implant bondingImplant bonding
A bonded interface is characteristic of a
cemented prosthesis (left)
non-bonded interface is characteristic of a non-
cemented press fit prosthesis (right)
Degradation ProblemsDegradation Problems
Example of fractured artificial cartilage from a failed hip replacement
BiocompatibilityBiocompatibility
The ability of a material to elicit The ability of a material to elicit an appropriate biological an appropriate biological response in a specific application response in a specific application by by NOTNOT producing a toxic, producing a toxic, injurious, or immunological injurious, or immunological response in living tissue.response in living tissue. Strongly determined by primary Strongly determined by primary
chemical structure.chemical structure.
Host Reactions to Host Reactions to BiomaterialsBiomaterials
ThrombosisThrombosis HemolysisHemolysis InflammationInflammation Infection and SterilizationInfection and Sterilization CarcinogenesisCarcinogenesis HypersensitivityHypersensitivity Systemic EffectsSystemic Effects
What are some of the What are some of the Challenges?Challenges?
To more closely replicate complex tissue To more closely replicate complex tissue architecture and arrangement architecture and arrangement in vitro.in vitro.
To better understand extracellular and To better understand extracellular and intracellular modulators of cell function.intracellular modulators of cell function.
To develop novel materials and To develop novel materials and processing techniques that are processing techniques that are compatible with biological interfaces. compatible with biological interfaces.
To find better strategies for immune To find better strategies for immune acceptance.acceptance.
Biomaterials - An Biomaterials - An Emerging IndustryEmerging Industry
Next generation of medical implants Next generation of medical implants and therapeutic modalities.and therapeutic modalities.
Interface of biotechnology and Interface of biotechnology and traditional engineering.traditional engineering.
Significant industrial growth in the Significant industrial growth in the next 15 years -- potential of a multi-next 15 years -- potential of a multi-billion dollar industry.billion dollar industry.
Biomaterials Companies
•Baxter International develops technologies related to the blood and circulatory system.
• Biocompatibles Ltd. develops commercial applications for technology in the field of biocompatibility.
• Carmeda makes a biologically active surface that interacts with and supports the bodys own control mechanisms
• Collagen Aesthetics Inc. bovine and human placental sourced collagens, recombinant collagens, and PEG-polymers
• Endura-Tec Systems Corp. bio-mechanical endurance testing ofstents, grafts, and cardiovascular materials
• Howmedica develops and manufactures products in orthopaedics.
• MATECH Biomedical Technologies, development of biomaterials by chemical polymerization methods.
• Medtronic, Inc. is a medical technology company specializing in implantable and invasive therapies.
• Molecular Geodesics Inc., biomimetic materials for biomedical, industrial, and military applications
• Polymer Technology Group is involved in the synthesis, characterization, and manufacture of new polymer products.
• SurModics, offers PhotoLink(R) surface modification technology that can be used to immobilize biomolecules
• W.L. Gore Medical Products Division, PTFE microstructures configured to exclude or accept tissue ingrowth.
• Zimmer, design, manufacture and distribution of orthopaedic implants and related equipment and supplies
