Evaluation of a Bioabsorbable Polyester Blend for Use in Medical Devices: CRANIOSORB~(TM), a Novel Cranial Fixation System

摘要

A novel cranial fixation system, Craniosorb~(TM), was developed using bioabsorbable, aliphatic polyester blends comprising a 50:50 mole:mole poly(50,50 D,L-lactide) (D,L-PLA) and a 95:5 mole mole poly(ε-caprolactone-co-p-dioxanone) (PCL:PDO). It was determined that compositions containing less than 10 weight percent of the PCL:PDO copolymer form an opaque, semi-crystalline blend that upon heating above the melting point of the copolymer soften and appear clear until cooled below the copolymer's melting point to yield a visual cue to allow the surgeon to non-destructively contour the now flexible plate to the irregularly shaped cranial and facial bones. Additionally, a novel, easy to deliver fastener system composed of an interference fitting poly(L-lactide) rivet/pin was developed. Physico-mechanical testing of the plate and rivet/pin system demonstrated sufficient strength retention for cranio-facial fracture fixation. It was also found that the absorbable plate and rivet/pin device was biocompatible and elicited minimal inflammatory response. Good bone healing was observed across the defect site. Additional biocompatibility studies demonstrated that the polymer is non-cytotoxic, non-mutagenic, and non-sensitizing.