Musculoskeletal conditions are a major health concern in United States because of a large aging population and increased occurrence of sport-related injuries. The need for bone substitutes is especially important. Traditional treatments of bone-defect have many of limitations. Bone tissue engineering may offer a less painful alternative to traditional bone grafts with lower risk of infection. This research integrates biomimetic modeling, solid freeform fabrication (SFF), systems and control, and tissue engineering in one intelligent system for structured, highly porous biomaterials, which will be applied to bone scaffolds. Currently a new SFF-based fabrication system has been developed, which uses a pressurized extrusion to print highly biocompatible and water soluble sucrose bone scaffold porogens. To date, this system can build simple bone structures. In parallel we are utilizing a commercial rapid prototyping (RP) machine to fabricate thermoplastic porogens of various designs to determine the feasibility of injecting a highly viscous scaffold material into porogens. Materials which have been successfully used to make scaffolds by injection include calcium phosphate cement (CPC), molten poly-caprolactone (PCL), 90/10 and 80/20 (v/v %) composite of PCL and calcium phosphate (CaPO4,). Results presented for the injection method include characterization of attainable feature resolution of the RP machine, as well as preliminary cell-biomaterial interaction data demonstrating biocompatibility of CPC scaffolds. The preliminary results using a commercial rapid prototyping machine have demonstrated that the indirect porogen technique can improve 2–4 folds the resolution of SFF system in fabricating bone scaffolds. The resultant scaffolds demonstrate that the defined porous structures will be suitable for tissue engineering applications.

1.
Evelyn B. Kelly, New Frontiers in Bone Grafting http://www.orthopedictechreview.com/issues/oct00/pg28.htm
2.
Laurencin
C. T.
,
Ambrosio
A. M. A.
,
Borden
M. D.
, and
Cooper
A.
,
Tissue engineering: orthopedic applications
.
Annu. Rev. Biomed. Eng.
1999
.
01
:
19
46
.
3.
Gadzag
AR
,
Lane
JM
,
Glaster
D
,
Forster
RA
,
Alternative to autogenous bone graft: efficiency and indication
.
J. Am. Acad. Orthop. Surg.
1995
.
3
:
1
8
.
4.
Mrunal
S. S
,
Tissue engineering: chanllenges and opportunities
,
J. Biomed. Mater. Res.
,
2000
, Vol.
53
pp.
617
620
5.
Mikos
AG
,
Bao
Y
,
Cima
Lg
,
Ingber
DE
,
Vacanti
JP
,
Preparation of poly (glycolic acid) boneded fiber structures for cell attachment and transplantation
.
J Biomed. Mater. Res.
,
1993
, Vol.
27
, pp.
183
189
6.
Leatrese
D. Harris
,
Byung-Soo
Kim
,
David
J. Mooney
,
Openpore biodegradable matrices formed with gas foaming
,
J. Biome. Mater. Res.
,
1998
. Vol.
42
, pp.
396
402
7.
Coombes
A. G. A.
and
Heckman
J. D.
,
Gel Casting of resorbable polymers 1 and 2
,
Biomaterials
,
1992
, Vol.
13
, pp.
217
224
8.
Singhal
AR
,
Agrawal
CM
,
Athannasiou
KA
,
Salient degration features of a 50:50 PLA/PGA scaffold for tissue engineering
,
Tissue Engineering
,
1996
, Vol.
2
pp.
197
207
9.
David
J. Mooney
,
Daniel
F. Baldwin
,
Nam
P. Suh
,
Joseph
P. Vacanti
and
Robert
Langer
,
Novel approach to fabricate porous sponges of poly(D, L-lactic-co-glycolic acid) without the use of organic solvents
,
Biomaterials
,
1996
, Vol.
17
, pp.
1417
1422
10.
A.E. Lange and M. Bhavnani, Solid freeform fabrication using stereolithography, SAMPE Journal, Vol. 30, No. 5, September/October 1994
11.
Sodian
R
,
Application of stereolighography for scaffold fabricarion for tissue engineering of heart valves
,
ASAIO Journal
,
2000
, Vol.
46
, pp.
238
238
12.
N.L. Porter, Fabrication of porous calcium polyphosphate implants by solid freeform fabrication: a study of processing parameters and in vitro degradation characteristics.
13.
Hutmacher
Dietmar W.
,
Scaffold in tissue engineering bone and cartilage
,
Biomaterials
,
2000
, Vol.
21
, pp.
2529
2543
14.
Park
A
,
Wu
B
,
Griffith
LG
,
Integration of surface modification and 3–D fabrication techniques to prepare patterned poly (L-lactide) substrates allowing regionally selective cell adhesion
,
J. Biomat. Sc
,
1998
, Vol.
9
, No.
2
, pp.
89
110
15.
Chu
T-M. G.
,
Halloran
J. W.
,
Hollister
S. J.
, and
Feinberg
S. W.
,
Hydroxyapatite implants with controlled internal architecture
,
J. of Materials Science: Materials in Medicine
,
12
:
471
478
,
2001
16.
Burg
Karen J. L.
,
Porter
Scott
,
James
F. Kellam
,
Biometarial development for bone tissue engineering
,
Biomaterials
, Vol.
21
,
2000
, pp.
2347
2359
17.
Brekke
John H.
,
Toth
Jeffrey M.
,
Principle of tissue Engineering applied to programmable osteogesis
,
J. Biomed Mater Res
Vol.
43
pp.
380
398
,
1998
.
18.
Freyman
T. M.
,
Yannas
I. V.
,
Gibson
L. J.
,
Cellular materials as porous scaffold for tissue engineering
,
Progress in Materials science
,
2001
, Vol.
46
, pp.
273
282
19.
Klawitter
JJ
,
Hulbert
SF
,
Application of porous ceramics for the attachment of load bearing orthopedic applications
,
J. Biomed. Mat. Res. Sym.
1971
, Vol.
2
pp.
161
161
20.
Athanasiou
KA
,
Zhu
,
Lanctot
DR
,
Wang
X
,
Fundamentals of biomechanics in tissue engineering of bone
,
Tissue Engineering
,
2000
, Vol.
6
, pp.
361
381
21.
Chen
C. S.
,
Yannas
I. V.
and
Spector
M.
,
Pore strain behavior of collagen-glycosaminoglycan analogues of extracellular matrix
,
Biomaterials
, Vol.
16
,
1995
, pp.
777
783
22.
Temenoff
Jonathan S.
,
MIlkos
Antonios G.
,
Injectable biodegradable materials for orthospedic tissue engineering
,
Biomaterials
,
2000
, Vol.
21
pp.
2405
2412
23.
P. Quinten Ruhe, Elizabeth L. Hedberg, Nestor Torio Padron, Paul H.M. Spauwen, John A. Jansen, DDS, AND Antonios G. Mikos, rhBMP-2 Release from Injectable Poly(DLLactic-co-glycolic Acid)/ Calcium-Phosphate Cement Composites, THE JOURNAL OF BONE AND JOINT SURGERY, 2003, pp. 75–81
24.
Haines
AH
.
1981
.
Selective removal of protecting groups in carbohydrate chemistry
.
Adv Carbohydr Chem Biochem
39
:
13
70
.
25.
Khan
R.
1984
.
Chemistry and new uses of sucrose: How important?
Pure Appl Chem
56
:
833
844
26.
Rubio
E
,
Fernandez-Mayoralas
A
,
Klibanov
AM
.
1991
.
Effect of the solvent on enzyme regioselectivity
.
J Am Chem Soc
113
:
695
696
.
27.
Xu
H. H.
,
Simon
C. G.
,
Self-hardening calcium phosphate composite scaffold for bone tissue engineering
.
J. Orthop. Res.
2004
.
22
(
3
):
535
43
.
28.
Xu
H. H.
,
Quinn
J. B.
,
Takagi
S.
,
Chow
L. C.
,
Synergistic reinforcement of in situ hardening calcium phosphate composite scaffold for bone tissue engineering
.
Biomaterials
.
2004
.
25
(
6
):
1029
37
.
29.
Barralet
J. E.
,
Grover
L.
,
Gaunt
T.
,
Wright
A. J.
,
Gibson
I. R.
,
Preparation of macroporous calcium phosphate cement tissue engineering scaffold
.
Biomaterials
.
2002
.
23
(
15
):
3063
72
.
30.
Nikolaychik
VV
,
Wankowski
DM
,
Samet
MM
,
Lelkes
PI
,
In vitro testing of endothelial cell monolayers under dynamic conditions inside a beating ventricular prosthesis
.
ASAIO J.
1996
;
42
(
5
):
487
-
94
.
31.
Nikolaychik
VV
,
Samet
MM
,
Lelkes
PI
,
A new method for continual quantitation of viable cells on endothelialized polyurethanes
.
J Biomater Sci Polym Ed
.
1996
;
7
(
10
):
881
91
.
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