LEUKOCYTE ACCUMULATION AND LEUKOTRIENE-B-4 RELEASE IN RESPONSE TO POLYGLACTIN-910 AND EXPANDED POLYTETRAFLUOROETHYLENE IN HOLLOW CHAMBERS IN THE RAT

The acute inflammatory reaction elicited after implantation of polymer membranes used clinically to promote bone healing and augmentation wa s studied in a soft tissue titanium chamber model. The two materials c ompared were non-degradable expanded polytetrafluoroethylene (ePTFE) a nd degradable polyglactin 910, a copolymer of 90% polyglycolic acid an d 10% polylactic acid. The membranes were implanted in the titanium ch amber for 24 h and 6 d. The number of leucocytes increased for both ma terials, whereas the leukotriene B-4 (LTB(4)) content decreased over t ime. In both groups polymorphonuclear granulocytes predominated. The n umber of leucocytes was significantly higher in chambers with polyglac tin 910 than ePTFE. In contrast, the LTB(4) content was higher in cham bers with ePTFE than polyglactin 910. No differences in cell viability were observed between the materials tested. This study shows that bot h degradable and non-degradable polymers elicit a marked influx and ac tivation of inflammatory cells during early healing in soft tissues.