1. Literature Review
Bioactive Materials
by Wanpeng Cao & Larry L. Hench
Sept 20th 2012
By : Leon Valentino
Advisor : Prof. Shao-Ju Shih

2. Main Objective
• To Study about what is:
 Tissue attachment
 General Theory of Biomaterials
 Bioactivity
 Bioactive Ceramics
 Mechanism of Bioactive Bonding
 Bioactive Coating and Composites
Nano Materials and Grain Boundary Engineering Lab 2

3. Tissue attachment of Biomaterials
1. Nearly Inert
Host Tissue Response Implant 2. Porous
3. Bioactive
4. Resorbable
1. Morphological fixation
2. Biological fixation
3. Bioactive fixation
4. Replacement with tissue
Nano Materials and Grain Boundary Engineering Lab 3

4. Tissue response to near inert implant
Host Tissue Nearly Inert implant
Response
Non-adherent fibrous capsule
(mechanical lock)
Micromotion More reactive
Degradation of Thicker Non-
adherent fibrous
implan/tissue capsule layer
Nano Materials and Grain Boundary Engineering Lab 4

5. Tissue response to porous biomaterial implant
Host Tissue Porous biomaterial
implant
Response
Ingrowth of tissue into
pores (biological fixation)
Capable of
withstanding more
complex stress
Provide blood
supply
Nano Materials and Grain Boundary Engineering Lab 5

6. Tissue response to Bioactive Material
Host Tissue Bioactive
Response Material
Series of biophysical and
biochemical reaction occur at
interface
Mechanically
strong chemical
interfacial bond
Nano Materials and Grain Boundary Engineering Lab 6

7. Tissue response to Resorbable Material
Host Tissue Resorbable
Response Material
Resorbable material degrade
gradually and replace by natural
tissue
Must Rate of degradation
metabolically must equivalent to
accepted regeneration rate
Nano Materials and Grain Boundary Engineering Lab 7

8. General Theory of Biomaterial by Hench and
Ethridge
a) Ideal implant material perform as if it
equivalent to host tissue
b) Axiom 1. The tissue at interface should be
equivalent to normal host tissue
c) Axiom 2. Response of the material to physical
stimuli should be like that tissue it replaces.
Nano Materials and Grain Boundary Engineering Lab 8

9. Bioactivity
Bioactive Elicit biological response at
material interface that form bond
Create osteogenesis environment
Time for more than 50% of interface
Bioactivity
bonded
Nano Materials and Grain Boundary Engineering Lab 9

10. Class in bioactive materials
Bioactive
Material
Class A Class B
(Osteoproductive) (Osteoconductive)
Elicit intracellular Elicit extracellular
Elicit extracellular
response response
response
Nano Materials and Grain Boundary Engineering Lab 10

11. Bioactive ceramics
• Base component in most bioactive glass and
ceramics (traditional) are SiO2, Na2O,CaO and P2O5.
• By comparing composition of SiO2-Na2O-CaO with
P2O5 constant, a diagram of bioactivity are like this:
Nano Materials and Grain Boundary Engineering Lab 11

12. Bioactive Bonding
Do not depend on
Stage 1-5 the presence of
tissues.
Nano Materials and Grain Boundary Engineering Lab 12

13. Interaction implant-tissue
• Extracellular interaction => determined by
surface features (important for protein and
collagen adsorption)
• Intracellular interaction => caused by soluble
silicon release from glass surface. Soluble
silicon => potent mitogen => enhanced
alkaline phospatase activity and osteocalcin
(product of resorption of bone) release
Nano Materials and Grain Boundary Engineering Lab 13

14. Calcium Phosphate Ceramics
Precipitation
Hydrothermal reaction
Calcium Phosphate Sol-Gel
Solid state reaction
Hydrolysis
Nano Materials and Grain Boundary Engineering Lab 14

15. Biological apatite and Synthetic HA
Biological Apatite (HCA) Synthetic HA
Contains carbonate (3.2-5.8 wt%) Much more Isotropic than biological
apatite
Contains minor element (Mg,Na,K) and Much larger in grain size
trace element (Sr,Pb,Ba) and acid
phosphate.
Contains organic material which exist in
grain boundaries and has large influence
to physical-chemical and biological
properties
Nano Materials and Grain Boundary Engineering Lab 15

16. Bioactive Composite and Coating
Bioactive Composites
and Coating
Have much better
biomechanical
properties than
bioactive ceramics
Nano Materials and Grain Boundary Engineering Lab 16

17. Bioactive Composite
Bioactive Composites
Matrix : Bioactive glasses/glass- Matrix : biocompatible Polymer
ceramics
Reinforce : metal fibers or tough Reinforce : Bioactive
ceramic part glass/ceramic particle or fibers
Mechanical properties
Elastic moduli > bone close to bone
Stress shielding
Nano Materials and Grain Boundary Engineering Lab 17

18. Bioactive Composite
Nano Materials and Grain Boundary Engineering Lab 18

19. Bioactive coating
Solve mechanical limitation for load-
bearing application
Use Metals and alumina (medical grade)
Bioactive Coating as susbtrate coated by HA,TCP,Bioglass
Calcium Phospate deposit using
HIP, plasma/flame spraying,ion beam
sputtering, sol-gel deposition and RF
sputtering
Good for short term stabilization but cannot
be used for long term due to deficiencies
Nano Materials and Grain Boundary Engineering Lab 19

20. Conclusion
• There are many factors influence bioactivity
such as Morphology (surface
morphology,pores), composition, mechanical
properties,etc.
• To achieve biochemically and biophysically
strong interface between host tissues-implant
is very important
Nano Materials and Grain Boundary Engineering Lab 20

21. Future Work
• Produce MBG using Sol-Gel methode for temp
400 C and 600C
Nano Materials and Grain Boundary Engineering Lab 21

22. Nano Materials and Grain Boundary Engineering Lab 22