Histological Evaluation of the Local Soft Tissue Reaction After Implanting Resorbable and Non-resorbable Monofilament Fibers.

BACKGROUND

The development of technologies and scientific disciplines connected with medical implantation devices is dynamically affecting modern treatments by contemporary medicine and veterinary medicine; it also entails a need to monitor their impact on living organisms.

OBJECTIVES

The aim of the study was to conduct a comparative histological evaluation of the response of soft tissues after implanting monofilament fibers from resorbable glyconate and from non-resorbable polypropylene (PP) and polyamide (PA) in rats.

MATERIAL AND METHODS

Non-resorbable polyamide-based fibers were applied to skin anastomoses in rats. Macroscopic and histological evaluations were performed on the 7th, 14th and 30th days. Non-resorbable polypropylene fibers and resorbable glyconate fibers (composed of 72% glycolide, 14% trimethylene carbonate and 4% caprolactone) were implanted in muscle tissue for periods of 7, 14, 30 and 90 days.

RESULTS

A semi-quantitative and qualitative histological evaluation found different dynamics and degrees of intensification of cell and tissue response around the resorbable and non-resorbable fibers being tested. The resorption process of the glyconate threads caused a prolonged inflammatory cellular response compared to the non-resorbable threads; it passed, however, without the participation of giant cells. Around the non-resorbable threads the observed cellular response was less intensified, with the formation of single polymorphonuclear macrophages around the PP threads, along with a stronger degree of fibrosis and the presence of fatty infiltrate.

CONCLUSIONS

During the early period, moderately intensified inflammatory cell response with the presence of single giant cells was observed around the non-degradable PA and PP fibers. In the late period, a band of fibrous connective tissue was present around the PP threads. Glyconate fibers underwent fragmentation and the process of resorption, which was associated with a weakly intensified inflammatory process lasting up to 90 days after implantation.