The development of bioresorbable composite polymeric implants with high mechanical strength

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Polymer Chemistry

Background:

• Tissue defect implants require mechanical mimicry, resorbability, and biocompatibility.
• Current materials often lack optimal combinations of these properties.

Purpose of the Study:

• To develop and characterize a novel composite scaffold for tissue defect repair.
• To evaluate the mechanical properties, resorbability, and biocompatibility of the developed scaffold.

Main Methods:

• Braiding poly(glycolic) acid variants into scaffolds.
• Coating scaffolds with crosslinked poly(glycolide-co-caprolactone) elastomer.
• Mechanical testing (compression, expansion, elasticity).
• In vivo studies in porcine and ovine models for resorbability and biocompatibility.

Main Results:

• Composite scaffolds demonstrated significantly enhanced mechanical strength (compression, expansion, elasticity) compared to uncoated braids.
• Scaffolds exhibited expansion properties comparable to metallic stents.
• Optimized mechanical properties by tuning elastomer branching, crosslink density, and molecular weight.
• Scaffolds were highly resorbable in porcine femoral arteries and fully resorbed by 18 months in ovine femoral arteries.
• Maintained an expanded open lumen for 12 months in vivo.

Conclusions:

• The developed composite scaffold effectively mimics native tissue mechanical properties.
• The scaffold is resorbable and biocompatible, supporting tissue regeneration.
• This technology presents a promising alternative to metallic stents for treating vascular defects.