Page 284 - IJB-10-4

International Journal of Bioprinting 3D printing prosthesis for palatal fistula

while the water contact angle of silicone rubber maintained to silicone rubber may be attributed to the Ra value of
at around 100°. This indicates that the hydrophilicity of PU PU prosthesis falling into this range. To ensure excellent
is much better than that of silicone rubber. hydrophilicity and comfort of wearing PU elastomer,

In the case of oral prosthesis, the extracts enter the maintaining surface roughness at moderate level should be
digestive system directly. According to the standard (ISO taken into consideration.
10139-2-2016), the water absorption and solubility of the As shown in Figure 6G, the friction coefficient of PU
printing ink substrate (PU ,PU , and PU ) were tested after prosthesis is higher than that of silicone rubber, potentially
2
3
1
a full light curing. As shown in Figure 6C and D, the WSP contributing to improved retention and stability within the
3
did not exceed 20 μg/mm in any of the five samples in oral cavity. We aim to implement a comprehensive friction
each group, and the WSL of these samples did not exceed performance test in future to enhance the functionality of
3
3 μg/mm , proving that these PU materials have fulfilled PU prosthesis and ultimately realize their full potential in
the standard’s requirements. After complete light curing clinical applications.
of five different components of printing inks, except for
Elastomer , the Shore-A hardness of the other groups was 3.5. Tensile property and compressive property tests
1
less than 50 HA (Figure 6E). of light-curable PU elastomers
The AFM results showed that the average roughness Both Elastomer and Elastomer returned to their original
4
2
of the prosthesis was 8.306 nm (Figure 6F). The surface state after compression. Furthermore, the two elastomers’
morphology and roughness of silicone rubber used for oral stress–strain (Figure 7B and D) and force–displacement
and maxillofacial restoration have been assessed in another curves (Figure 7A and C) display apparent differences
study, which revealed an Ra value ranging from 0.28 to 1 in their mechanical properties. As shown in Figure 7G,
50
nm. The higher hydrophilicity of PU prosthesis compared the tensile strength of Elastomer is higher than that of
4

Figure 7. Tensile property and compressive property tests of light-cured polyurethane (PU) elastomers. (A) Force–displacement curves of Elastomer and
2
Elastomer in tensile test. (B) Stress–strain curves of Elastomer and Elastomer in tensile test. (C) Force–displacement curves of Elastomer and Elastomer 4
4
2
4
2
in compression test. (D) Stress–strain curves of Elastomer and Elastomer in compression test. (E) The tensile strength of Elastomer is higher than that of
4
4
2
Elastomer in the compression test. (F) The tensile moduli of both elastomers do not exhibit statistical difference. (G) The compressive strength of Elastomer 4
2
is higher than that of Elastomer . (H) The Young’s modulus of Elastomer is higher than that of Elastomer . Notes: ns, p > 0.05; *p < 0.05; **p < 0.01.
2 4 2
Volume 10 Issue 4 (2024) 276 doi: 10.36922/ijb.2516