Synthesis, structure, and properties of carbon/carbon composites artificial rib for chest wall reconstruction

Abstract

In this work, braided carbon fiber reinforced carbon matrix composites (3D-C/C composites) are prepared by chemical vapor infiltration process. Their composite structure, mechanical properties, biocompatibility, and in vivo experiments are investigated and compared with those of traditional 2.5D-C/C composites and titanium alloys TC4. The results show that 3D-C/C composites are composed of reinforced braided carbon fiber bundles and pyrolytic carbon matrix and provide 51% open pores with a size larger than 100 μm for tissue adhesion and growth. The Young's modulus of 3D-C/C composites is about 5 GPa, much smaller than those of 2.5D-C/C composites and TC4, while close to the autogenous bone. 3D-C/C composites have a higher tensile strength (167 MPa) and larger elongation (5.0%) than 2.5D-C/C composites (81 MPa and 0.7%), and do not show obvious degradation after 1 × 10⁶ cyclic tensile loading. The 3D-C/C composites display good biocompatibility and have almost no artifacts on CT imaging. The in vivo experiment reveals that 3D-C/C composites artificial ribs implanted in dogs do not show displacement or fracture in 1 year, and there are no obvious proliferation and inflammation in the soft tissues around 3D-C/C composites implant. Our findings demonstrate that 3D-C/C composites are suitable for chest wall reconstruction and present great potentials in artificial bones.

Figure 1

Architecture of preform for C/C composites, (a) 2D-C/C composites; (b) 2.5D-C/C composites; (c) 3D-C/C composites, respectively.

Figure 2

SEM of C/C composites, surface morphology, (a), (b), (e) 3D-C/C composites, (c), (d) 2.5D-C/C composites; EDS analysis, (f) 3D-C/C composites, respectively.

Figure 3

Pore analyses of 3D and 2.5D-C/C composites, (a) cumulative pore volume; (b) incremental intrusion volume, respectively.

Figure 4

Mechanical properties curve of C/C composites, tensile, (a) 3D-C/C composites, (b) 2.5D-C/C composites under static condition; (c) 3D-C/C composites, (d) 2.5D-C/C composites after fatigue; flexural, (e) 3D-C/C composites, (f) 2.5D-C/C composites, respectively.

Figure 5

MG-63 cells proliferation rate of 2.5D-C/C composites, 3D-C/C composites, and TC4, the control group is listed as reference.

Figure 6

CT images of materials implanted into the shinbone of pig legs (Sample is in the dotted circle), (a–c) for 3D-C/C composites, 80 × 12 × 3.4 mm in dimension; (d–f) for 2.5D-C/C composites, 55 × 12 × 3.4 mm in dimension; (g–i) for TC4, 55 × 12 × 3.4 mm in dimension, respectively.

Figure 7

HE stained histological cross-sections of soft tissues of 3D-C/C composites artificial rib implantation after 1 year, joint between 3D-C/C composites artificial rib implant and ribs, (a) ×100, (b) ×400; 3D-C/C composites surface, (c) ×100, (d) ×400, respectively.