Dispensing technique is one of the promising solid freeform (SFF) methods to fabricate scaffolds with controllable pore sizes and porosities. In this paper, a model to represent the dispensing-based SFF fabrication process is developed. Specifically, the mechanical properties of the scaffold material and its influence on the fabrication process are examined; the flow rate of the scaffold material dispensed and the pore size and porosity of the scaffold fabricated in the process are represented. In order to generate scaffold strands without either tensile or compressive stress, the optimal moving speed of the dispensing head is determined from the flow rate of the scaffold material dispensed. Experiments were also carried out to illustrate the effectiveness of the model developed.

1.
Griffith
,
L. G.
, and
Naughton
,
G.
, 2002, “
Tissue Engineering-Current Challenges and Expanding Opportunities
,”
Science
0036-8075,
295
, pp.
1009
1014
.
2.
Sachlos
,
E.
, and
Czernuszka
,
J. T.
, 2003, “
Making Tissue Engineering Scaffolds Work. Review on the Application of Solid Freeform Fabrication Technology to the Production of Tissue Engineering Scaffolds
,”
Eur. Cells Mater
1473-2262,
5
, pp.
29
40
.
3.
Yan
,
Y.
,
Xionga
,
Z.
,
Hu
,
Y.
,
Wang
,
S.
,
Zhang
,
R.
, and
Zhang
,
C.
, 2003, “
Layered Manufacturing of Tissue Engineering Scaffolds Via Multi-Nozzle Deposition
,”
Mater. Lett.
0167-577X,
57
, pp.
2623
2628
.
4.
Li
,
Q.
, and
Lewis
,
J. A.
, 2003, “
Nanoparticle Inks for Directed Assembly of Three-Dimensional Periodic Structures
,”
Adv. Mater.
,
15
, pp.
1639
1643
. 0935-9648
5.
Xie
,
B.
,
Parkhill
,
R. L.
,
Warren
,
W. L.
, and
Smay
,
J. E.
, 2006, “
Direct Writing of Three-Dimensional Polymer Scaffolds Using Colloidal Gels
,”
Adv. Funct. Mater.
1616-301X,
16
, pp.
1685
1693
.
6.
Chen
,
X. B.
,
Li
,
M. G.
, and
Ke
,
H.
, 2008, “
Modeling of the Flow Rate in the Dispensing-Based Process for Fabricating Tissue Scaffolds
,”
ASME J. Manuf. Sci. Eng.
1087-1357,
130
(
2
), pp.
021003
.
7.
Vozzi
,
G.
,
Previti
,
A.
,
Rossi
,
D.
, and
Ahluwalia
,
A.
, 2002, “
Microsyringe-Based Deposition of Two-Dimensional and Three-Dimensional Polymer Scaffolds With a Well-Defined Geometry for Applications to Tissue Engineering
,”
Tissue Eng.
1076-3279,
8
, pp.
1089
1098
.
8.
Xu
,
M.
,
Gratson
,
G. M.
,
Duoss
,
E. B.
,
Shepherd
,
R. F.
, and
Lewis
,
J. A.
, 2006, “
Biomimetic Silicification of 3D Polyamine-Rich Scaffolds Assembled by Direct Ink Writing
,”
Soft Matter
1744-683X,
2
, pp.
205
209
.
9.
Sampath
,
T. K.
, and
Reddi
,
A. H.
, 1984, “
Importance of Geometry of the Extracellular Matrix in Endochondral Bone Differentiation
,”
J. Cell Biol.
0021-9525,
98
, pp.
2192
2197
.
10.
Mikos
,
A. G.
,
Sarakinos
,
G.
,
Lyman
,
M. D.
,
Ingber
,
D. E.
,
Vacanti
,
J. P.
, and
Langer
,
R.
, 1993, “
Prevascularization of Porous Biodegradable Polymers
,”
Biotechnol. Bioeng.
0006-3592,
42
, pp.
716
723
.
11.
Khan
,
A. U.
,
Briscoe
,
B. J.
, and
Luckhan
,
P. F.
, 2001, “
Evaluation of Slip in Capillary Extrusion of Ceramic Pastes
,”
J. Eur. Ceram. Soc.
0955-2219,
21
, pp.
483
491
.
12.
Kalyon
,
D. M.
,
Yaras
,
P.
,
Aral
,
B.
, and
Yilmazer
,
U.
, 1993, “
Rheological Behavior of a Concentrated Suspension: A Solid Rocket Fuel Stimulant
,”
J. Rheol.
0148-6055,
37
, pp.
35
53
.
13.
Yeow
,
Y. L.
,
Lee
,
H. L.
,
Melvani
,
A. R.
, and
Mifsud
,
G. C.
, 2003, “
A New Method of Processing Capillary Viscometry Data in the Presence of Wall Slip
,”
J. Rheol.
0148-6055,
47
, pp.
337
348
.
14.
Hibbeler
,
R. C.
, 1999,
Mechanics of Material
, 4th ed.,
Prentice-Hall
,
Englewood Cliffs, NJ
.
You do not currently have access to this content.