Materials in bone tissue engineering

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Materials in bone tissue engineering

• 29 March 2004
• Abby Morgan

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Bone Grafts

• Natural
• Autograft
• Bone from the patient
• Donor site required
• Allograft
• Bone from another person
• Bone banks

• Synthetic
• Metals
• Ceramics
• Polymers

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Biomaterials Research Group 2004
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Metals

• Examples
• Stainless steel
• Co-Cr-Mo
• Ti-6Al-4V
• Uses
• Total joint replacement
• Plates

http//www.ikasassociates.com/private/plates1.htm
http//www.wmt.com/Physicians/Products/Hips/CONSER
VETotalHipSystem.asp
Biomaterials Research Group 2004
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Ceramics

• Examples
• Hydroxyapatite
• Main mineral phase of bone
• Coral or mineral
• Bioactive glass
• Uses
• Bone filler
• Scaffolds
• Plates

http//www.finnfacts.com/english/main/actualities/
bioglass.htm http//www.emedicine.com/orthoped/top
ic611.htmtarget1
Biomaterials Research Group 2004
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Polymers

• Examples
• Synthetic
• Poly(lactide-co-galactide)
• Polycaprolactone
• Natural
• Chitosan
• Gelatin
• Uses
• Bone extenders
• Scaffolds
• Drug delivery

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Biomaterials Research Group 2004
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Why we need more than a scaffold
Implant scaffold
Cytokines released
Proteins attach
Blood vessels invade
bone
Cells arrive
Nutrients blocked, wastes trapped
Cells lay down extra cellular matrix
Pores fill in
Cells in center die
Cells attach, proliferate and differentiate
Scaffold failure
Biomaterials Research Group 2004
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Tissue Engineering
the science of persuading the body to
regenerate or repair tissues that fail to
regenerate or heal spontaneously -C. M.
Agrawal
scaffold
Scaffold alone
Scaffold w/ growth factor
host tissue
Scaffold w/ cells growth factor
Scaffold w/ cells
Biomaterials Research Group 2004
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Ideal Bone Scaffold

• Characteristics
• Biodegradable
• Interconnected porosity
• Biocompatible
• Handleablity
• Osteoconductive or osteoinductive
• Cheap

• Examples
• Hydroxyapatite
• PLGA
• Gelatin
• Chitosan

Biomaterials Research Group 2004
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Bone Substitutes
Demineralized bone matrix (Allogro by Wright
Medical Technologies)
Immix Extenders, a particulate polymer bone graft
extender (Osteobiologics, Inc)
Hydroxyapatite from chemically treated sea coral.
(ProOsteon and Interpore by Cross International,
Inc.)
Polymer-based bone graft substitutes (Cortoss and
Rhakoss, both produced by Orthovita, Inc.)
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