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International Journal of Bioprinting 3D-printing silicone patient-specific soft-tissue expander

Figure 4. The comma- and heart-shaped mandibular bone defect expanders: (a) cross-section; (b) 3D computer-aided design (CAD) models; (c) perforated
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guide molds with a hole density of 0.038 hole/mm .

based on a cross-section at the midpoint of the defect The right-sided mandibular defect extended from the
part. The cross-sectional shape of the defect part roughly right second premolar to the distal end, and the same
resembled a heart-shaped structure with approximately method (as described above) was used to reconstruct
18 mm length and 15 mm width. The total length of the the right-sided defect part (Figure 6a and b). For the
original defect part was about 40 mm, but an extension to patient-specific soft-tissue silicone expander design, the
60 mm was made to accommodate the sealing positions silicone membrane was also based on a cross-section at
of the silicone membrane at both ends (Figure 5b and c). the midpoint of the defect part model. The middle cross-
As the volume of the defective part was approximately section shape of the defect part resembled a kidney shape,
4240 mm , 2.2 expansion tablets were placed into the with a length of approximately 13 mm and a width of about
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silicon membrane. After sealing both ends of the outer 6.5 mm. The total length of the defective part measured
membrane, a patient-specific soft-tissue silicone expander approximately 40 mm, and similarly, allowed for sealing
was fabricated, incorporating 271 perforations (with a positions at both ends of the silicone membrane, resulting
diameter of 0.65 mm and a density of 0.038 hole/mm ) in the final length of 60 mm (Figure 6b and c). Considering
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to facilitate liquid diffusion based on a surface area of the volume of the bone defect part to be around 5960 mm ,
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7369 mm . three expansion tablets would be required. Upon sealing
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Volume 10 Issue 4 (2024) 570 doi: 10.36922/ijb.2918