Figures & data
Figure 1. MicroCT analysis of salt-leached, photopolymerized scaffold fabricated with Kerr dental lamp. The material was methacrylate end-capped poly(D,L-lactide), and camphorquinone has been used as photoinitiator.
![Figure 1. MicroCT analysis of salt-leached, photopolymerized scaffold fabricated with Kerr dental lamp. The material was methacrylate end-capped poly(D,L-lactide), and camphorquinone has been used as photoinitiator.](/cms/asset/60498798-2970-4c11-a3c9-6bd62791e65e/iann_a_288347_f0001_b.gif)
Figure 3. Schematic representation of the stereolithography (SLA) system. An ultraviolet (UV) laser is used to solidify the model's cross-section while leaving the remaining areas in liquid form. The movable table then drops by a sufficient amount to cover the solid polymer with another layer of liquid resin.
![Figure 3. Schematic representation of the stereolithography (SLA) system. An ultraviolet (UV) laser is used to solidify the model's cross-section while leaving the remaining areas in liquid form. The movable table then drops by a sufficient amount to cover the solid polymer with another layer of liquid resin.](/cms/asset/8b664033-3933-48dd-aa92-2941b1aadaed/iann_a_288347_f0003_b.jpg)
Figure 4. Example of a scaffold fabricated using stereolithography (SLA). A: Computer-aided design (CAD) image of the structure. B: Completed SLA-fabricated scaffold with very regular pore size distribution. C: Microcomputerized tomography (microCT) image of the scaffold.
![Figure 4. Example of a scaffold fabricated using stereolithography (SLA). A: Computer-aided design (CAD) image of the structure. B: Completed SLA-fabricated scaffold with very regular pore size distribution. C: Microcomputerized tomography (microCT) image of the scaffold.](/cms/asset/d08dfc96-2b43-4d44-8a03-03753c58dc58/iann_a_288347_f0004_b.jpg)
Figure 5. Scheme of 3D printing process. A stream of adhesive droplets is expelled through an inkjet printhead, selectively bonding a thin layer of powder particles to form a solid shape.
![Figure 5. Scheme of 3D printing process. A stream of adhesive droplets is expelled through an inkjet printhead, selectively bonding a thin layer of powder particles to form a solid shape.](/cms/asset/022748be-fa24-4d47-be8f-13279eb0c9e1/iann_a_288347_f0005_b.jpg)
Figure 6. Scheme of selective laser sintering (SLS) technique. The laser selectively fuses powdered material by scanning cross-sections generated from a 3D digital description of the part on the surface of a powder bed. After each cross-section is scanned, the powder bed is lowered by one layer thickness, a new layer of material is applied on top, and the process is repeated until the part is completed.
![Figure 6. Scheme of selective laser sintering (SLS) technique. The laser selectively fuses powdered material by scanning cross-sections generated from a 3D digital description of the part on the surface of a powder bed. After each cross-section is scanned, the powder bed is lowered by one layer thickness, a new layer of material is applied on top, and the process is repeated until the part is completed.](/cms/asset/4efeba8d-e149-4dd6-9781-1060f0f3ca8e/iann_a_288347_f0006_b.jpg)
Figure 7. Scheme of the fused deposition modeling (FDM) system. FDM uses a moving nozzle to extrude a fiber of polymeric material from which the physical model is built layer by layer.
![Figure 7. Scheme of the fused deposition modeling (FDM) system. FDM uses a moving nozzle to extrude a fiber of polymeric material from which the physical model is built layer by layer.](/cms/asset/02d27e0e-998f-4e37-a5ef-a9183b27030e/iann_a_288347_f0007_b.jpg)
Figure 8. Sketch of the 3D Bioplotter® system. The material is plotted through the nozzle into a liquid medium with matching density. The material solidifies when it comes in contact with the medium. The liquid medium compensates for gravity, and hence no support structure is needed.
![Figure 8. Sketch of the 3D Bioplotter® system. The material is plotted through the nozzle into a liquid medium with matching density. The material solidifies when it comes in contact with the medium. The liquid medium compensates for gravity, and hence no support structure is needed.](/cms/asset/5e4bf57c-0480-4b2e-9023-c8d03fe226f0/iann_a_288347_f0008_b.jpg)
Figure 9. The principle of the two-photon polymerization process. Overlap of photons from the ultrashort laser pulse leads to chemical reactions between monomers and starter molecules within the transparent matrix.
![Figure 9. The principle of the two-photon polymerization process. Overlap of photons from the ultrashort laser pulse leads to chemical reactions between monomers and starter molecules within the transparent matrix.](/cms/asset/f73d992b-0813-4d2d-8e84-7d0d9eb4f3c5/iann_a_288347_f0009_b.jpg)
Table I. Comparison of different rapid prototyping (RP) methods on the basis of their achievable resolution, advantages, and disadvantages.