3D-printed poly-4-hydroxybutyrate bioabsorbable scaffolds for nipple reconstruction

Nipple reconstruction remains a challenge due to scar contracture and loss of projection with current techniques. Autologous tissue methods and engineered substitutes often fail to maintain shape over time. Unprocessed costal cartilage has been proposed as a support but results in overly firm structures. This gap motivated the exploration of new scaffold materials that could resist contractile forces while allowing tissue ingrowth. Prior research has shown that bioabsorbable scaffolds can support tissue regeneration, but none have specifically addressed the biomechanical needs of the reconstructed nipple. The need for a material that balances structural support with eventual absorption remains unmet. Scar contracture continues to limit patient satisfaction with existing techniques. The search for a scaffold that mimics native tissue properties is ongoing.

The aim of this work is to develop a 3D-printed scaffold that maintains projection in reconstructed nipples while allowing tissue regeneration. The specific problem is the loss of shape and function due to scar contracture. The motivation is to create a scaffold that resists contractile forces and supports tissue ingrowth. The study focuses on using poly-4-hydroxybutyrate (P4HB) as a bioabsorbable scaffold material. The goal is to test whether this scaffold can maintain projection over time. The study also investigates whether adding processed costal cartilage or a 3D P4HB lattice improves outcomes. The researchers propose that this scaffold could be used in clinical settings for patient-specific reconstructions. The ultimate aim is to improve patient satisfaction by preserving shape and biomechanics.

The researchers designed a 3D-printed scaffold using poly-4-hydroxybutyrate (P4HB), a bioabsorbable polymer. The scaffold was filled with either processed costal cartilage or a 3D P4HB lattice. The constructs were implanted in vivo for 6 months to observe tissue ingrowth. Scanning electron microscopy (SEM) was used to assess scaffold absorption and tissue integration. Histological analysis evaluated the formation of fibrovascular cartilaginous tissue. The study compared scaffolded reconstructions with non-scaffolded controls. The biomechanical properties of the neo-nipples were measured against native tissue. The internal lattice structure of the scaffold was analyzed for its effect on absorption and tissue regeneration.

After 6 months in vivo, neo-nipples with scaffolds showed significantly greater projection than those without. Fibrovascular cartilaginous tissue formed in scaffolds filled with processed costal cartilage. Scaffolds with an internal 3D lattice of P4HB filaments absorbed more quickly than others. SEM and histological analysis confirmed vascularized tissue formation in lattice-filled scaffolds. The neo-nipples maintained biomechanical properties similar to native tissue. The fastest absorption was observed in scaffolds with a 3D P4HB lattice and no cartilage. Tissue ingrowth was most pronounced in scaffolds with processed costal cartilage. The authors suggest that the scaffold design influences both absorption rate and tissue regeneration.

The authors propose that 3D-printed P4HB scaffolds resist scar contracture and maintain projection in reconstructed nipples. The study suggests that scaffolds filled with processed costal cartilage support tissue ingrowth. Scaffolds with an internal P4HB lattice absorb more rapidly and promote vascularized tissue. The neo-nipples maintained biomechanical properties of native tissue after 6 months. The authors suggest that the scaffold design is a key factor in tissue regeneration. They propose that this scaffold could be used in clinical settings for patient-specific reconstructions. The results suggest that the scaffold is a viable alternative to current techniques. The authors believe this scaffold is ready for translation into clinical applications.