[Clinical and histopathological study of tissue reactivity to monofilament suture materials: nylon and poliglecaprone 25 in rats].

PURPOSE The aim of this experimental study was to evaluate through a clinical and histopathological analysis the tissue reactivity caused by two monofilament sutures nylon and poliglecaprone 25 on the internal and external sutures in rats. METHODS For this study, we used forty male Rattus novergicus (Wistar rats). The experimental procedures were incisions and divulsions performed on the back of the animals' thighs. Internal and external sutures were done on the right thigh using nylon 0-5, and on the left thigh using poliglecaprone 25 0-5. The animals were distributed in 4 groups of 10 rats, according postoperatory period on the 7, 14, 21 and 28 days, G1 (7th day), G2 (14th day), G3 (21th day) and G4 (28th day). The clinical assessment aimed to verify the existence of dehiscence, exsudate and edema. The histopathologic analysis was intended to evaluate the inflammatory reaction, foreign body giant cells, fibroblastic proliferation and fibrosis. RESULTS Clinically, no changes were found on groups studied. Histopathological analysis inflammatory reaction, foreign body giant cells, fibroblastic proliferation and fibrosis were higher on the internal sutures with nylon. On the sutures done with poliglecaprone 25 showed an increase in tissue reactivity passing postoperatory period. CONCLUSIONS On the basis of the methodology used in the study, it was concluded that external sutures done with nylon produce less tissue reactivity; on internal sutures, however, this material contributes to the maintenance of the tissue reaction. The external sutures done with poliglecaprone 25 showed a greater tissue reaction; on the external sutures the tissue reaction decreased while the thread was being absorbed.