seminar
DESCRIPTION
tissueTRANSCRIPT
Tissue engineering scaffolds for cleft palate
Nachanadar Rujimarmahasan
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content
I. Cleft lip and palate
II. Stem cell research
III. Tissue model constructs & lab techniques
IV. Craniofacial research
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Objectives• The ability to engineer anatomically correct pieces of viable and
functional human bone would have tremendous potential for bone reconstructions after congenital defects
• Design and Modifying Model to create Smart biomaterial scaffolds that improve tissue regeneration
• Biocompatible and biodegradable • Biomaterial scaffolds that are immunologically inert• Stem cell can be patient specific using their own isolated cells,
reducing risk of rejection
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Understanding cleft lip and palate. 1: An overview
• The normal anatomy of the face
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Anatomy
cleft palate
normal
cleft lip and cleft palate
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Cleft lip and palate
Patients with clefts: (A) incomplete unilateral cleft of the lip, (B) unilateral cleft of the lip, alveolus, and palate, (C) bilateral cleft of the lip, alveolus, and palate,
(D) isolated (median) cleft palate.
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Problems with Disorder • Breastfed• hearing (the Eustachian tube) glue ear• Speech• Functions• Cosmetic• Psychology• Dental• Swallowing• facial growth
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Obturator
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Care plan timetable• birth to 6 weeks: counseling for parents, hearing test and
feeding assessment • 3 months: surgery to repair a cleft lip • 6-12 months: surgery to repair a cleft palate • 18 months: speech assessment • 3 years: speech assessment • 5 years: speech assessment • 8-11 years: bone graft to the cleft in the gum area (alveolus) • 11-15 years: orthodontic treatment and monitoring jaw growth • 18 years+: if needed, jaw surgery, lip and nose revision surgery,
and final replacements for any missing teeth
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Problems
Be the angel for cleft lip and cleft palate children: What you can do to help?
If orthodontic and the oral surgeon treatment failure
Decreases the extent of surgery required for repairing the lip and palate.
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OUTCOME
• Developed a biomimetic scaffold for tissue engineering
• That provides a cell-instructive structural framework • For inducing differentiation of stem cells into
osteogenic cells. • This porous and matrix have increaded stiffness • Which can facilitate its use in load-bearing bone
tissue engineering.
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Hypothesis
Tissue engineering
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Tissue model constructs &
lab techniques
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biomimetic
biomimetic of bone regeneration14
Biomimetic Scaffold Fabrication
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Engineering bone grafts
• Change stem cells into bone cells – with proper growth
factors in cell culture media
• This scaffold can’t be too big or the cells inside will die since they will not get enough oxygen
A 3D calcium phosphate scaffoldFrom Becton Dickinson
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Biomimetic Platforms for
Human Stem Cell Research
Gordana Vunjak-Novakovic,Volume 8, Issue 3, 4 March 2011, Pages 252–261
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stem cell science and bioengineering
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Biomimetic Paradigm Stem cell fate and function
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Scaffold-Bioreactor Systems for Human Stem Cells
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Craniofacial Bone regeneration
• clinically sized • anatomically shaped • viable human bone grafts stem cells• biomimetic” scaffold-bioreactor system.
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Engineering anatomically shaped human bone grafts
Warren L. Grayson, 2010
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Tissue engineering of anatomically shaped bone grafts.
Grayson W L et al. PNAS 2010;107:3299-3304
©2010 by National Academy of Sciences 23
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Grayson W L et al. PNAS 2010;107:3299-3304
©2010 by National Academy of Sciences
Tissue Development and Mineral Deposition
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Bone formation was markedly by perfusion
Grayson W L et al. PNAS 2010;107:3299-3304
©2010 by National Academy of Sciences 26
Architecture of the mineralized bone matrix
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Bone matrix morphology
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Biomaterials & scaffolds for tissue engineering
Fergal J. O'Brien, Volume 14, Issue 3, March 2011, Pages 88–95
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Confocal micrograph
Fig. 1. Confocal micrograph showing osteoblast cells (green) attached to a highly porous collagen-GAG scaffold (red).
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composite scaffolds
Fig. 2. Comparative SEM images of (a) collagen-GAG (CG) scaffold (b) hydroxyapatite (HA) and (c) composite collagen-HA (CHA) scaffold.
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collagen scaffolds for bone tissue engineering
Fig. 3. Effect of hydroxyapatite addition on (a) stiffness and (b) permeability of collagen scaffolds.
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cell-mediated mineralization
Fig. 4. Quantitative cell-mediated mineralization by osteoblasts on the CHA scaffolds containing differing amounts of HA
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degradation in rat calvarial defect
Fig. 5. Example of core degradation in a rat calvarial defect treated with a tissue engineered collagen-calcium phosphate scaffold 4 weeks post implantation.
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engineer microvasculature
Fig. 6. In vitro microvessel formation by endothelial cells on the scaffold.
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conclusion
Scaffold requirements• Biocompatibility• Biodegradability• Mechanical properties• Scaffold architecture
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conclusion• ideal scaffold should have several
characteristics: – (i) high porosity for cell/tissue growth,
nutrient diffusion, matrix production and vascularization;
– (ii) controllable degradation to match tissue growth once implanted in body and
– (iii) reasonable mechanical strength to match the tissues at the site of implantation
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