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International Journal of Bioprinting Property of scaffolds with different lattices

largest proportion of shear stress at 0–20 MPa. Therefore, types of unit cell structures in porous titanium alloy
despite the fact that the average shear stress of the diamond scaffolds can impact the number of adhered cells but have
scaffold is lower than that of the CPL and cuboctahedron minimal effect on the state of cell adhesion. The growth
scaffolds, the diamond scaffold has a more concentrated of MC3T3-E1 cells on the cuboctahedron scaffolds was
shear stress distribution and is more effective in promoting the lowest after 3 days of culture. Cuboctahedrons did not
cell differentiation. ALP activity and calcium deposition on demonstrate evident advantages in terms of specific surface
the diamond scaffold were considerably more pronounced area and permeability, which are linked to additional
than those on the other two groups 14 and 30 days after space and nutrients for cell proliferation. ALP activity
induction, showing that the diamond scaffold was more detection is useful for assessing the functional condition
favorable to fostering osteoblast development. The results of osteoblasts. At the earliest stage of differentiation, we
demonstrated that with the same porosity and pore size, found no statistically significant variation in ALP activity
the CPL scaffold had a greater specific surface area than the between titanium alloy scaffolds with different pore shapes
cuboctahedron scaffold, while the diamond scaffold had (P > 0.05). At 14 days, the ALP activity of the diamond
the smallest specific surface area. Theoretically, a larger scaffold was substantially greater than that of CPL and
specific surface area endows more space for cell adhesion. cuboctahedron (P < 0.05). Mineralized nodules are the
However, there are some discrepancies between our in vitro ultimate manifestation of the osteogenic phenotype of
cell tests and theoretical prediction. After 3 h of culture, the osteoblasts in vitro, as well as a sign of mineralized matrix
number of adhered cells on the diamond scaffolds was only development. The mineralized nodules could be dissolved
marginally higher than that on the CPL scaffolds (P > 0.05) by 10% cetyl pyridine chloride, and the absorbance value
but significantly higher than that on the cuboctahedron was proportional to the calcium ion content. After the
scaffold (P < 0.05). Despite the bigger specific surface dissolution of mineralized nodules, the diamond scaffold
area, the lower permeability of CPL scaffold limits the exhibited the highest OD value, which was much higher
cells from entering the scaffold for adherence, explaining than those of CPL and cuboctahedron scaffolds (P < 0.05).
the insignificant difference in cell adherence between the
two scaffolds. Consistent with the results of our fluid simulation
research, it can be extrapolated that the diamond
In a study about local curvature and pore shape, Bael scaffold has a greater influence on inducing osteogenic
et al. determined that obtuse angles were more likely to differentiation of MC3T3-E1 cells. To further elucidate
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obstruct cells than acute angles. According to Urda et al., the aforementioned impacts, the expression levels of
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straight edges and convex surfaces in pore structure are osteogenesis-related genes, namely ALP, Runx2, and
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detrimental to cell development. Huang et al. discovered OCN, were measured quantitatively. In the process of bone
that the porous titanium alloy scaffold with dodecahedron matrix mineralization, OCN expression is the primary
unit cell exhibited superior osseointegration performance indication of osteogenic differentiation, and Runx2 is
after studying the osseointegration performance of titanium one of the most significant transcription factors for
alloy scaffolds with two unit cells (diamond and rhombic osteoblast differentiation. The results demonstrated that
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dodecahedron). Xu et al. compared the osseointegration the expression of osteogenic genes on the diamond scaffold
properties of two unit cells (a hollow hexagonal prism and was superior to that on the cuboctahedron scaffold, while
a hollow triangular prism) through animal experiments. expression was lowest on the CPL scaffold. We expected
They found that a hollow hexagonal prism had more new that the diamond porous titanium alloy scaffold would
bone ingrowths. Changes in pore shape have a significant promote osteogenic differentiation more effectively.
effect on the osseointegration efficiency of porous titanium The lateral femoral epicondyle of rabbits was implanted
alloy scaffolds. with three types of Ti6Al4V scaffolds with various unit
In this study, the effects of the three pore configurations cells. Three months after feeding, an X-ray inspection
on the adhesion, proliferation, and differentiation of revealed that all scaffolds had successfully fused with the
MC3TE-E1, a mouse osteoblast precursor cell line, were surrounding bone, and there was no evidence of prosthesis
compared. Staining with acridine orange revealed that loosening or displacement. Micro-CT 3D reconstruction
a substantial percentage of MC3T3-E1 cells adhered also confirmed the creation of new bone inside and around
to the three titanium alloy scaffolds. The percentage of the scaffold. Quantitative research revealed that the amount
MC3T3-E1 cells attached to scaffolds can be ranked in the of new bone surrounding the three scaffolds did not differ
following order: diamond > CPL > cuboctahedron. Using significantly; however, the amount of new bone inside the
SEM and phalloidin/DAPI labeling, it was determined scaffolds is ranked in this order: diamond > cuboctahedron
that MC3T3-E1 cells adhered well to all three scaffolds, > CPL, and the difference was statistically significant (P <
with no significant differences between them. Different 0.05). Titanium alloys are inert materials and do not release

Volume 10 Issue 2 (2024) 223 doi: 10.36922/ijb.1698