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Biodegradable Calcium Phosphate Biodegradable Calcium Phosphate Ceramics and Their ApplicationsCeramics and Their Applications

Sukyoung KimSukyoung Kim

Yeungnam University Yeungnam University School of Materials School of Materials

EngineeringEngineering

The Aged = Needs of Biomaterials

15.9

69.4

14.5

14.7

68.1

17.2

14.3

66.1

19.6

14.3

65

20.7

14.3

63.6

22

14.2

60.6

25.2

13.7

59.5

26.9

13.1

59.5

27.4

0%

20%

40%

60%

80%

100%

1995 2000 2005 2010 2015 2020 2025 2030

< 일본의 향후 인구비율 >

고령인구의 증가율 (7%->14%)스웨덴 85 년영 국 45 년일 본 24 년한 국 ? 년

65 세 이상 ( 노년인구 )

15∼65 세

0∼14 세 ( 소년인구 )

( 일본 국세도회 2000/2001)

고령인구증가

질병발생빈도증가

Life Span & Quality by Medical Treatment

Life Span50 80

LifeQuality

과거 현재 21 세기

치료의학

예방의학 재활의학 산업적효과

0

10

20

30

40

50

60

1995 1997 1999 2001 2003 2005 2007 2009

Year

Market Size(billion $)

World Market Size of Biomaterials

• 연평균 성장률 15% • 2000 년도부터는 예측한 값 ( 미국 , DATAMONITOR, Inc., 조사자료 )

Applications of Biomaterials

재건장치 50%

기타 10%척추 이식재 6%

외상 관련 14%

연 조직 관련 10% 관절내시경 및 스포츠약품 10%

☞ 최근 아시아를 중심으로 수요의 급증으로 세계시장이 15% 안팎의 성장을 보임 (2000 년 2 분기 , Biomet Inc. 조사 )

ORTHOPEDICSFracture fixationJoint prosthesis

DENTISTRY Dentalimplants

OPHTHALMOLOGYCorneas

Artificial lenses

CARDIOVASCULARSURGERYCardiac valve

Arterial segments

PLASTIC SURGERY

Cosmeticimplants

34

521

CERAMICSAlumina (1,2,3,5)Zirconia (1,2)Glass-ceramics (2,3)Pyrocarbon (1,4)HA (1,2,3,5)Porcelain (2)C-C composite (1)

POLYMERS

METALSTi/Ti-alloy (1,2,4)Stainless steel (1)Co-Cr-Mo alloy (1,2)Ni-Ti (1,2,4)Amalgam (2)

Polyethylene (1,4,5)Silicone (3,5)Polyurethane (3,4,5)Acrylates (4)

Biomaterials and Their ApplicationsBiomaterials and Their Applications

대체 가능한 인공장기

Current Trend of Bio R&D

• Gene Theraphy - Congenital Deformity/Disease

• Biomaterials - Congenital Deformity/Disease- Postnatal Deformity/Disease

BiomaterialsBiomaterials

Tissue Tissue Engineering Engineering

Grafting

Current R&D Trend of Biomaterials

Natural & Artificial Biomaterials

Tissue/Organ

Scaffold

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Introduction to BioceramicsIntroduction to Bioceramics

Biomaterials

• Biologically Derived Materials- Autografting- Allografting- Xenografting

• Artificially Synthesized Materials- Polymers- Metals- Ceramics- Composites

Why Increase the Use of Biomaterials ?

• Increase old ages• Increase of the wounded by war/accident• Health insurance • Pursuit of better quality of life• Development of new biomaterials

& medical technology

Artificial BiomaterialsArtificial Biomaterials

For Soft TissueFor Soft Tissue - Polymers- Polymers- Composites- Composites

For Hard TissueFor Hard Tissue - Metals- Metals- Ceramics- Ceramics- Composites- Composites

Why Use the Artificial Biomaterials ?

(problems of the use of natural materials)

• Shortage of natural biomaterials• High cost• Immunologic reactions• Possible viral transmission

• Social and ethical problems

Ceramics for BiomaterialsCeramics for Biomaterials

GoodGood - hardness- hardness - strength- strength- chemical inertness - chemical inertness - light- light- friction / wear- friction / wear - - biocompatibilitybiocompatibility

BadBad - brittleness- brittleness - processing- processing- cost- cost - strength- strength

Why Ceramics ?Why Ceramics ?

Biocompatibility Biocompatibility - bioinert- bioinert- bioactive- bioactive- bioresorbable- bioresorbable

HardnessHardness Friction / WearFriction / Wear LightLight

Classification of Biological ActivityClassification of Biological Activity

BioinertBioinert AlAl22OO33

ZrZrOO22

Dense HA with high Dense HA with high crystallinitycrystallinity

BioactiveBioactive BioglassBioglassHA with low crystallinityHA with low crystallinity

BioresorbableBioresorbable TCPTCPCMPCMPGypsumGypsumCaOCaO

Biomaterial

Fibrous Tissue Bone

(a) Bioinert (c) Bioresorbable(b) Bioactive

Reactions Between Bone & BiomaterialsReactions Between Bone & Biomaterials

BioceramicsBioceramics

Metal OxidesMetal Oxides AlAl22OO3 3 , Zr, ZrOO2 2

Calcium PhosphatesCalcium Phosphates- - HA [ hydroxyapatite ; CaHA [ hydroxyapatite ; Ca1010(PO(PO44))66(OH)(OH)22 ] ]- - -TCP [ tricalcium phosphate ; Ca-TCP [ tricalcium phosphate ; Ca33(PO(PO44))22 ] ]- CMP [ calcium metaphosphate ; Ca(PO- CMP [ calcium metaphosphate ; Ca(PO33))22 ] ]

Glass & Glass-CeramicsGlass & Glass-Ceramics - - Bioglass [ Na Bioglass [ Na22O-CaO-SiOO-CaO-SiO22-P-P22OO55 system ] system ]

- Ceravital [ Na- Ceravital [ Na22O-CaO-SiOO-CaO-SiO22-P-P22OO55 system ] system ]- A/W or Cerabone [ apatite-wollastonite:- A/W or Cerabone [ apatite-wollastonite: 3CaO. P3CaO. P22OO55 -CaO.SiO -CaO.SiO22-MgO.CaO.2SiO-MgO.CaO.2SiO22 ] ]

Graphite, CarbonGraphite, Carbon fiber, diamond, pyrolitic carbonfiber, diamond, pyrolitic carbon crystalline and noncrystalline crystalline and noncrystalline

carboncarbon

R

R

R

Current Problems of the Use of BioceramicsCurrent Problems of the Use of Bioceramics

BrittlenessBrittleness

Processing / CostProcessing / Cost

Interfacial Bonding Strength Interfacial Bonding Strength

between Coating and Substratebetween Coating and Substrate

Forms of BioceramicsForms of Bioceramics

MonolithicMonolithic CompositeComposite Coating Coating

PowderPowder PorousPorous DenseDense FiberFiber

Why Porous ?Why Porous ? tissue ingrowthtissue ingrowth tissue contact areatissue contact area bone filler, substitutebone filler, substitute

Why Fiber ?Why Fiber ? reinforcement in reinforcement in

compositecomposite adjust mechanical adjust mechanical

propertyproperty bone plate, stembone plate, stem

Why Coating ? Why Coating ? biocompatibilitybiocompatibility osseointegrationosseointegration HA, Bioglass, CMPHA, Bioglass, CMP

Why Dense ? Why Dense ? wear / frictionwear / friction strengthstrength teeth, hip-ballteeth, hip-ball

Why Powder ?Why Powder ? tissue growthtissue growth fillerfiller

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Hydroxyapatite (HA)Hydroxyapatite (HA)

For bone substitutionFor bone substitution(cement, filler)(cement, filler)& coating& coating

Calcium Phosphate CeramicsCalcium Phosphate Ceramics

Various Calcium Phosphates with Ca/PVarious Calcium Phosphates with Ca/P

Ca/PCa/P Formular Formular Name Name Abbreviation Abbreviation 0.500.50 Ca(HCa(H22POPO44))22HH22OO mono-Ca-P monohydrate mono-Ca-P monohydrate MCPM MCPM1.001.00 CaHPOCaHPO44 dicalcium phosphate (monetite) dicalcium phosphate (monetite) DCP DCP1.001.00 CaHPOCaHPO4.4.2H2H22OO di-Ca-P dihydrate (brushite) di-Ca-P dihydrate (brushite) DCPD DCPD1.331.33 CaCa88HH2(2(POPO44))66.5H.5H22O tetracalcium dihydrogen phosphateO tetracalcium dihydrogen phosphate TDHP TDHP1.501.50 CaCa33(PO(PO44))22 tricalcium phosphate (α,β,γ) tricalcium phosphate (α,β,γ) TCP TCP1.671.67 CaCa1010(PO(PO44))66(OH)(OH)22 hydroxyapatite hydroxyapatite HA HA2.002.00 CaCa44O(POO(PO44))22 tetracalcium phosphate tetracalcium phosphate TTCP TTCP

0.500.50 Ca (POCa (PO33))22 calcium metaphosphate (α,β,γ,δ) calcium metaphosphate (α,β,γ,δ) CMP CMP1.001.00 CaCa22PP22OO77 calcium pyrophosphate (α,β,γ) calcium pyrophosphate (α,β,γ) CPP CPP

Degree of BiodegradationDegree of Biodegradation(( Osseointegration or Bone Bonding) Osseointegration or Bone Bonding)

Chemical CompositionChemical Composition (Ca/P) (Ca/P) Chemical BondingChemical Bonding Chemical Species (Additives)Chemical Species (Additives) CrystallinityCrystallinity Density (surface area)Density (surface area) Environment (pH, temperature)Environment (pH, temperature)

Hydroxyapatite, CaHydroxyapatite, Ca1010(PO(PO44))66(OH)(OH)22

Main component of bone Main component of bone and tooth mineralsand tooth minerals

Ca/P ratio : 1.67Ca/P ratio : 1.67

• Excellent biocompatibilityExcellent biocompatibility Chemically similar to boneChemically similar to bone

~ 97 wt % of enamel~ 97 wt % of enamel ~ 69 wt % of cortical bone~ 69 wt % of cortical bone

Inorganic69 % (HA)

Water 9 %

Organic(collagen) 22 %

Applications of HA CeramicsApplications of HA Ceramics

Powder Powder

Blocks Blocks

3 Types of Ceramics for Bone Substitutes3 Types of Ceramics for Bone Substitutes

Block• 기계적 안정• 피부절개수술 필요• 가공필요

Powder• 가공 불필요• 피부절개수술 필요• 기계적 불안정

Injectable• 가공 불필요• 피부절개수술 불필요 ( 주사기로 가능 )

BMP/DrugPowder + Liquid

chemical composition chemical composition particle size additives pore size additives

PastepHtemperatureratio (liquid/powder) ~ 0.35

Injectable Bone SubstitutesInjectable Bone Substitutes

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ITYCalcium Phosphate CeramicsCalcium Phosphate Ceramics

Tissue EngineeringTissue Engineering

Interfaces of Implant-Tissue

• Biomaterials vs. Tissues Non-viable vs. Viable

materials

• Bioinert - (Fibrous Tissue) - Bone Bioactive - (Interface) - Bone Bioresorbable - (Substitution) - Bone

Prosthesis

• Transplantation- fully functional biological substitute - autogenesis, allogenesis, xenogenesis- tissue engineered materials

• Implantation- non-biological substitute- bioinert implant (permanent foreign body) - bioresorbable implant (temporary foreign b.)

Autogenic Bone Transplantation

• Ideal bone substitute• Providing essential elements for bone healing

- osteoconduction - osteoinduction - osteogenic cells

• Limitation of autogenic bone • Substantial morbidity

- infection, malformation, pain, loss of function

Allogenic Bone Grafting

• Best alternative as an osteoconductive implants

• Possible disease transmission• Host rejection• Lack of osteoinduction

Methodology of Bone Tissue Generation

• With in vitro cell culture - in vitro tissue regeneration & implantation

- in vivo tissue regeneration by implantation of scaffold with cell

• Without in vitro cell culture - in vivo tissue regeneration

by implantation of scaffold without cell

Segmental Bone Defect Repairs

Rat femur at 4 (top) & 8 weeks (bottom)

VariousImplantation

of Porous

Ceramics

H. Ohgushi

Tissue Engineering

• Generation of new tissue substitutes for the replacement & repair

of lost or damaged tissue

Cell + Scaffold = Tissue natural ECM synthetic ECM

Goal of Tissue Regeneration

(Man-made) (God-made)

by tissue engineering

CellCellSynthetic ECMSynthetic ECM

CellCellNatural ECMNatural ECM

CellCellNatural ECMNatural ECM

Autogenic Autogenic MaterialsMaterials

Tissue EngineeredTissue EngineeredMaterialsMaterials

Osteoconductive MaterialsOsteoconductive Materials - allogenic - allogenic - synthetic - synthetic

++Osteoinductive MaterialsOsteoinductive Materials - - DBMDBM - - BMPBMP

Tissue Regeneration Therapy

MonoclonalMonoclonal AntibodiesAntibodies (MAb)(MAb)

Isolation andIsolation andPurificationPurification

Harvest boneHarvest bonemarrowmarrow

MSCsMSCs

MarrowMarrowMesenchymalMesenchymal

Stem Cells (MSCs)Stem Cells (MSCs)

Cryo-PreserveCryo-Preservefor future use Culture-Expanded MSCsCulture-Expanded MSCs

Repopulate marrowRepopulate marrow Push to OsteoblastPush to Osteoblast Push to ChondrocytePush to Chondrocyte

HemapoiesisHemapoiesisSupportSupport

Normal boneNormal boneHomeostasisHomeostasis(Anti-aging)(Anti-aging) MassiveMassive

bone repairbone repair

Repair cartilage Repair cartilage defectdefect

Porous Ceramic Assay

DispersedDispersedMarrowMarrow

DisectDisectPeriosteumPeriosteum

PorousPorousCeramicsCeramics

MSCsMSCs

PassagePassage

SubcutaneousSubcutaneous

Bone Regeneration in Human Bone

Marrow Harvest

Isolate MSC

Expand MSC

Incorporate intoPorous Ceramic

Implant for BoneAugmentation

External Fixation

Requirements for Cell Transplantation Scaffolds

• Biocompatibility• Pore size and Morphology• Biodegradation Rate• Mechanical properties • Easy processing (3-D, size, shape)• Controlled release system (incorporating drugs or growth & differentiation factors)

Biomaterials (Scaffold or Matrix) in Tissue Engineering

• Natural materials - Proteins of natural ECM

(collagen, glycosaminoglycan)• Synthetic materials - Biodegradable polymers (PLA, PGA, PLGA) - Biodegradable ceramics (CMP, TCP, HA)

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ITYCalcium MetaphosphateCalcium Metaphosphate

(CMP)(CMP)

For Bone SubstitutesFor Bone Substitutes & Scaffolds& Scaffolds

Rationale of Biodegradable Implant

Implantation Time

Stre

ngth

(Mpa

) Implant Bone

Structure of Calcium Metaphosphate (CMP)Structure of Calcium Metaphosphate (CMP)

PP OO PPOO

OO

OO

OO

OO

Ca Ca 2+2+ n (large)

[Ca(PO3)2]n

NaNa++

[NaCa(PO3)3]n

NaNa++

PP11

PP22

PP33

PP11

PP22

PP33

PP11

PP22

PP33

CaCa2+2+

CaCa2+2+

CaCa2+2+

CaCa2+2+

PP11

PP22

PP33

PP11

PP22

PP33

PP11

PP22

PP33

CaCa2+2+

CaCa2+2+

NaNa++

Biodegradable Porous CMPBiodegradable Porous CMP

500 500 ㎛㎛

500 500 ㎛㎛

500 500 ㎛㎛

500 500 ㎛㎛

20 ppi

60 ppi

10 ppi

45 ppi

Wei

ght L

oss (

%)

Wei

ght L

oss (

%)

Immersion Time (days)Immersion Time (days)0 5 10 15 20 25

0

20

40

60

80

100

CMP5 % Na5 % Na22OO

10 % Na10 % Na22OO15 % Na15 % Na22OO20 % Na20 % Na22OO

25 % Na25 % Na22OO

Degradation of Na-CMP Glass in Degradation of Na-CMP Glass in D.W.D.W.

Wt Loss of Na-CMP Block in Tris-BufferWt Loss of Na-CMP Block in Tris-Buffer

Load

Bottom Plate

Cross Head

Spherical Seat

Spherical Bearing Block

Test Specimen

Bedding Material

Compression Test of Porous Ceramics

0 1 2 3 4 5 6 7 8-1.0

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

Pure 5 mol% Na2O

Com

pres

sive

Stre

ngth

( M

Pa )

Immersion Time (days)Immersion Time (days)

Strength of Na-CMP Block in Tris-BufferStrength of Na-CMP Block in Tris-Buffer

Biodegradable 3-D Porous CMP CeramicsBiodegradable 3-D Porous CMP Ceramicsfor Bone Substitutes & Tissue Engineeringfor Bone Substitutes & Tissue Engineering

With With

College of Dentistry College of Dentistry Seoul National UniversitySeoul National University

Porous CMP block

Rabbit’s Calvarial Defect After 6 Wks

Control group With CMP

After 6 week implantation in rabbit’s calvarial defect (high X)

CMP

B

B

Tissue response to CMP in subcutaneous tissue (after 6 weeks)

CMP

CT

Connective Tissue

Tissue response to CMP in rabbit’s thigh muscle (after 6

weeks)

Muscle

Connective Tissue CMP

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ITYOrthopedic & Dental ImplantsOrthopedic & Dental Implants

HA HA CoatingCoatingByBy Plasma Spray Method Plasma Spray Method

Alumina Balls for Hip ImplantsAlumina Balls for Hip Implants

Fixation of ImplantsFixation of Implants

• Cement FixationCement Fixation- Bone Cement PolyMethyl MethAcrylate (PMMA)

• Cementless FixationCementless Fixation- Metallic Porous Coating Bead, Wire, Mesh- Ceramic Coating on Metallic Implants HA [[CaCa1010(PO(PO44))66(OH)(OH)22]] ☜

Implant Type of attachment ExampleImplant Type of attachment Example

Nearly inert Mechanical interlocking AlNearly inert Mechanical interlocking Al22OO33

with thin fibrous encapsulationwith thin fibrous encapsulation

Porous Tissue in-growth into pores Porous HAPorous Tissue in-growth into pores Porous HA (biological fixation)(biological fixation)

Bioactive Interfacial bonding with tissues Bioactive glassesBioactive Interfacial bonding with tissues Bioactive glasses (bioactive fixation) Bioactive G-C(bioactive fixation) Bioactive G-C HAHA

Bioresorbable Replacement with tissue Bioactive glassesBioresorbable Replacement with tissue Bioactive glasses TCP, CMPTCP, CMP GypsumGypsum

Four Types of Implant-Tissue AttachmentFour Types of Implant-Tissue Attachment

Requirements of Biomaterials

• Bulk Properties- Mechanical compatibility (, , E)- Density- Biodegradation

• Surface Properties- Biological compatibility- Chemical compatibility- Bioresorbability

Surface Engineering of Metallic Implants

• Surface Treatment - Surface modification

- oxidation (passivation) - ion implantation

- Surface roughening - acidic/basic etching

- blasting – sand, TiO2, Al2O3, HA • Surface Coating

- Porous coating - bead, wire or mesh

- Non-porous coating - powder, granular, sol-gel

Various Porous Coating for ImplantsVarious Porous Coating for Implants

(ref) The biomedical engineering handbook, 683 (1995)

plasma sprayed sintered wire mesh sintered beads

Metallic Bead Coating for ImplantsMetallic Bead Coating for Implants

Coating-SubstrateCoating-Substrate Composite SystemComposite System

INTERFACEINTERFACE

COATINGCOATING

SUBSTRATESUBSTRATE

Biocompatibility Wear / Friction Erosion Electronic properties Corrosion / Oxidation Porosity Roughness

Residual stress Multi-layers Cohesion Graded composition Cracking/defects Adhesion

Adhesion Inter-diffusion Substrate properties Diffusion barriers Expansion mismatch Cleanliness/roughness

Mechanical properties Thermal properties

Depth of Surface Modification Depth of Surface Modification and Thickness of Coatingsand Thickness of Coatings

IIIAC

PVD

CVD & PACVDThermal Spraying

WeldingElectroplating

ThermochemicalSol - Gel

1010-1-1 11 1010 101022 101033 101044

Thickness (Thickness (m)m)

(Ion Implantation)(Ion Implantation)

(Ion Assisted Coating)

• Plasma sprayingPlasma spraying• Sol-gel coating Sol-gel coating • Laser coatingLaser coating• Dipping Dipping • SputteringSputtering• Electrochemical coatingElectrochemical coating• Thermal decomposition etc.Thermal decomposition etc.

Various Techniques of HA CoatingVarious Techniques of HA Coating

200HA Coating Thickness (m)

Adhesive Strength(MPa)

34

Adhesive Strength vs. HA ThicknessAdhesive Strength vs. HA Thickness

Plasma Spray Coating for ImplantsPlasma Spray Coating for Implants

PlasmaPlasma SprayingSpraying ProcessProcess

Cathode

Copper anode

Plasma

Spray stream

Substrate

Coating

Arc gas

Electrical connection

(+ve)

HA powder in carrier gas

Electrical connection

(-ve)

Arc chamber

HA Powders for Plasma Spray CoatingHA Powders for Plasma Spray Coating

Spray dried Roller crushed

Advantages of HA Coated ImplantsAdvantages of HA Coated Implants

세라믹 세라믹 ((HA) HA) 재료재료

생체친화성 화학적 적합성

금속 재료금속 재료 기계적 강도 가공성

+

• 임플란트에 대한 뼈의 빠른 결합 임플란트 주위에 두꺼운 섬유조직의 미발생 뼈와 임플란트의 단단한 결합 치료기간 단축 정확한 시술의 불필요 생리학적 , 면역학적 안정성 향상

HA Coating for ImplantsHA Coating for Implants

Fixation Methods of Current ImplantsFixation Methods of Current Implants

(a) Bone cement (b) Sintered Co-Cr Balls(c) Sintered Ti-alloy mesh or wire (d) HA coating

Implant

Bone

Three Different Surface Treated Implants Three Different Surface Treated Implants

(ref) K. Gotfredsen, et al, JBMR 29, 1223-31 (1995)

(a) Cylinder implants

(b) Screw implants

(a) TiO2 blasted + HA

(b) TiO2 blasted

(c) Machined

(ref) K. Gotfredsen, et al, JBMR 29, 1223-31 (1995)

Surface Morphology of ImplantsSurface Morphology of Implants SEM Profilometric Image

Test Results of Retrieved Implants Test Results of Retrieved Implants

3 weeks 12 weeks Torque B-to-I contact Torque B-to-I contact

(Nm) (%) (Nm) (%)

Screw ImplantsHA coated 101±6 28.5±4.1 117±9 24.1±3.8TiO2-blasted 46±9 20.7±4.2 45±5 22.5±3.1machined 20±2 9.7±2.2 32±5 12.5±4.2

Cylinder ImplantsHA coated 101±9 18.5±3.6 109±6 28.2±3.1TiO2-blasted 60±11 14.7±4.4 80±6 26.1±2.5machined 35±7 7.6±2.5 50±5 22.1±4.8

(ref) K. Gotfredsen, et al, JBMR 29, 1223-31 (1995)

Comparison Between Comparison Between HA Un-coated and Coated ImplantsHA Un-coated and Coated Implants

S.S.Fibrous tissue Bone

BoneHA Coated S.S.

Bone Bonding to HA Coated ImplantBone Bonding to HA Coated Implant

HA

BM

150 μm

• Faster bony adaptationFaster bony adaptation• Firmer bone-implant attachment Firmer bone-implant attachment • No fibrous tissue encapsulation No fibrous tissue encapsulation • Reduced healing time Reduced healing time • Tolerance of surgical inaccuraciesTolerance of surgical inaccuracies• Inhibition of metal ion releaseInhibition of metal ion release

Advantages of HA Coated ImplantsAdvantages of HA Coated Implants

• Defects and pores in HA layerDefects and pores in HA layer

• Chemically inhomogeneity in HA layer Chemically inhomogeneity in HA layer

• Weak interfacial bonding (spalling)Weak interfacial bonding (spalling)

• Degradation or resorption of HA layerDegradation or resorption of HA layer

Disadvantages of HA Coated ImplantsDisadvantages of HA Coated Implants

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ITYDental & Orthopedic ImplantsDental & Orthopedic Implants

HA HA CoatingCoatingByBy Sol-Gel MethodSol-Gel Method

Advantages of HA Coating Advantages of HA Coating by Sol-Gel Processby Sol-Gel Process

Sol-Gel derivedSol-Gel derivedHA-CoatingHA-Coating

Lower sintering temperatureLower sintering temperatureHA-coated layerHA-coated layer

homogeneous & smooth surfacehomogeneous & smooth surface

high crystallinityhigh crystallinity at low firing temperatureat low firing temperature

(as low as 900 )℃(as low as 900 )℃

Easy coatingEasy coating on simple &on simple &complex-shaped implantscomplex-shaped implants

Spin Coating MethodSpin Coating Method

ωω

SPIN-OFF

ωω

EVAPORATION

ωω

SPIN-UP

dω/dt = 0

DEPOSITION

Dip Coating MethodDip Coating Method

DEPOSITION& DRAINAGE

CONTINUOUS

1 3

2

3

DRAINAGE

IMMERSION

EVAPORATION

START-UP

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ITYDental & Orthopedic ImplantsDental & Orthopedic Implants

HA / HA-Glass / GlassHA / HA-Glass / Glass Coatings CoatingsBy Plasma Spray MethodBy Plasma Spray Method

Cross-Sections of HA and Glass /HA LayerCross-Sections of HA and Glass /HA Layer

• thermal expansion coefficient thermal expansion coefficient (×10(×10-6-6/ ; 30~400 )℃ ℃/ ; 30~400 )℃ ℃

HA HA 13.3 13.3 TiTi 8.7 8.7 Ti6Al4VTi6Al4V 9.4 9.4 Glass FritGlass Frit 7.8 7.8 from S. Marunofrom S. Maruno

Glass LayerGlass Layer

Ti6Al4VTi6Al4VHA coatedHA coated

Glass/HA coatedGlass/HA coated

smooth HA coating surfacesmooth HA coating surfaceby sol-gel processby sol-gel process

HAHA

Schematics of HA Coatings

GlassGlass

HAHATi-6Al-4VTi-6Al-4V

Glass + HAGlass + HA

Schematic of Bonding TestSchematic of Bonding Test

Tensile LoadTensile Load

Tensile LoadTensile Load

PinPin

Bonding Bonding AgentAgent

Ti-alloyTi-alloyHA CoatingHA Coating

Cross-Section of CoatingsCross-Section of Coatings

As-coatedAs-coated

Heat-treatedHeat-treated@ 630℃@ 630℃

HAHA HA + GlassHA + Glass

HAHAHAHA

GlassGlass

ResinResin Ti-alloyTi-alloy Ti-alloyTi-alloyResinResin

IV. 연 구 결 과

• 슬관절 임플란트

• Bone Support

• Bone Cement

IV. 연 구 결 과

• Bone Cement (Injectable) • Spine Cage

IV. 연 구 결 과

Thank You 감사합니다