Histopathologic and biomechanical comparisons of the properties of skin, sutured with an Iranian and a foreign brand Nylon suture in rat

This study was designed to elucidate the possible differences between Supa and Ethicon, nylon in suturing rat skin. 75 Female Spragne-dawley albino rats with mean weight 250g were used and randomly divided into three groups of 30, 30 and 15 rats. In 60 rats anesthesea was induced by ketamin and xylazin. Followed by surgical preparation, a 5cm abdominal skin incision was made and sutured by simple interrupted suture pattern. In group 1, 3/0 nylon, Supa product and in group 2, 3/0 nylon Ethicon product were used. 15 animals of each group were sacrificed on day 6th for histopathologic examination and the rest of the animals on day 13th for histopathologic and biomechanical examinations. 15 rats were sacrificed for biomechanical evaluation of normal skin. Histopathologic sections were stained by H&E and examined under light microscope for reepithelization, acanthosis, age of granulation tissue, type of predominant inflammatory cells, hyperemia and the presence of giant cells. Tissue repair in group 2 was significantly more mature than group 1 on day 6th (P?0.05). There was no significant difference between the two groups on day 13th. In biomechanical study, the following parameters were measured form load-elongation curve: linear starting point, yield point, ultimate strength, stiffness, ultimate strain, maximum stored energy and yield stored energy. The stiffness of group 1 samples was significantly more than group 2 (P?0.05). There were no significant differences between the two groups in other biomechanical parameters. According to the results of this study it can be concluded that concerning short term tissue reactions, Ethicon nylon suture is superior to Supa, though there was no significant histopathologic difference between the two groups on day 13. However, cystic structures were observed only in group 2. The biomechanical quality of group 2 was also superior to group 1