SILKBridge

SILKBridge is a bioabsorbable silk fibroin-based nerve guide (cuff) designed for surgical repair of peripheral nerve gaps up to 10 mm. It is a hollow tubular implant with semi-permeable, non-constrictive walls that guide axonal growth, protect the injured nerve, and allow nutrient influx while the implant is enzymatically absorbed as native tissue regenerates.

SILKBridge uses silk fibroin (Bombyx mori) in a three-layer wall design (native fiber textile intermediate layer, electrospun inner and outer layers) totaling up to 24 mg, whereas the predicate Neurolac TW uses a single homogenous poly(DL-lactide-co-ε-caprolactone) layer. Both are semi-permeable, non-constrictive bioabsorbable nerve guides with comparable mechanical properties and the same intended use.

ISO 10993-1 (biocompatibility framework), ISO 10993-5 (cytotoxicity), ISO 10993-23 (intracutaneous reactivity), ISO 10993-10 (sensitization), ISO 10993-11 (acute systemic toxicity and pyrogenicity), ISO 10993-4/ASTM F619/F756 (hemolysis), ISO 10993-6 (implantation), ISO 10993-17 and ISO 10993-18 (chemical characterization and toxicological risk assessment), and ASTM standards for mechanical properties.

SILKBridge is substantially equivalent to Neurolac TW Nerve Guide because both share the same intended use, indications (repair of peripheral nerve discontinuities ≤10 mm), operating principle, and fundamental technology. Minor differences in wall design and material do not raise new safety or effectiveness questions; biocompatibility testing confirms biological safety per ISO 10993-1, bench testing demonstrates comparable mechanical properties, and 12-month rat sciatic nerve injury studies show equivalent safety and functional recovery.