Biocompatibility In-vivo of Poly-L-lactide and Bioactive Glass Composite Substitute for Internal Fracture Fixation

Poly-L-lactide (PLLA) has been applied to bone replacement materials due to its good biocompatibility and biodegradability However, its lack of bioactivity and the release of acidic degradation products, which may lead to inflammatory responses, limit its application. Composite materials based on PLLA and bioactive glass (BG) were prepared by a moulding method and the screws were machined from the composites. The biocompatibility in vivo of PLLA/BG composite material was evaluated by haematoxylin and eosin staining, and the bone-bonding ability of PLLA/BG composite was also performed by using tetracycline staining, Von Kossa staining, Alizarin S red staining and Masson's trichromatic staining. Tissue responses evaluated for 1 to 12 weeks revealed that PLLA/BG implants were tissue tolerant and had nonbacterial inflammatory. PLGA/BG composite showed better histological compatibility than PVC implant in the in vivo study. A good ability of bone-bonding of PLLA/BG was determined by implantation into rabbit muscle and femoral condyle, and the mineralization appeared around the PLLA/BG implant materials. The results showed that PLLA/BG composites have good biocompatibility as absorbable materials for internal fracture fixation.