Ranges in healing times are shown for different tissues. SI, small intestine; LI, large intestine.
Sutures in Exotic Animals
Rodents
Due to extensive use of rodents in research, suture reaction in rodents has been studied extensively with studies evaluating many suture types in specific applications. Rats have been used extensively to compare suture materials in the body wall, subcutaneous tissues, skin, urogenital tract, gastrointestinal tract, and oral cavity.
Several studies have compared suture materials in the body wall, subcutaneous tissues, and skin using rodent models. A study evaluating polyglyconate, polyglactin 910, chromic gut, and polydioxanone in the body wall of rats showed that polyglyconate and polydioxanone caused significantly less inflammation 28 days following implantation (Sanz et al. 1988). When polyglytone 6211 was compared to poliglecaprone 25 in the body wall of rats, there was no significant difference in the inflammatory response 2 or 10 days following implantation (van Heerden 2005). Comparison of poliglecaprone 25, polyglactin 910, and polytetrafluoroethylene (Teflon) in subcutaneous tissues showed that poliglecaprone 25 caused significantly less inflammation 48 hours after implantation and polytetrafluoroethylene sutures caused significantly more inflammation and fibrosis 7, 14, and 21 days following implantation (Nary‐Filho et al. 2002). A study comparing polyglactin 910, catgut, silk, and polypropylene in the skin showed that polyglactin 910 caused significantly less inflammation over a period of 7 days (Yaltirik et al. 2003). Comparison of polydioxanone, poliglecaprone 25, and Glycomer 631 in rat skin showed that poliglecaprone 25 and Glycomer 631 were less reactive than polydioxanone, but all three were acceptable due to extremely low reaction scores (Molea et al. 2000). When polyglytone 6211 was compared to chromic gut for skin closure in rats, polyglytone 6211 had significantly less tissue drag and less potentiation for infection when surgical wounds were inoculated with Staphylococcus aureus (Pineros‐Fernandez et al. 2004).
Several studies have been performed comparing suture materials in the urogenital tracts of rats with the aim to evaluate inflammation, fibrosis, and adhesion formation. A comparison of polyglactin 910 and polyglycolic acid in uterine tissue showed that there was significantly less inflammation and fibrosis with polyglactin 910 90 days following implantation (Riddick et al. 1977). Another study evaluating suture material in uterine tissues compared polyglycolic acid, polyglactin 910, polydioxanone, silk, and polypropylene. The results showed that polydioxanone caused the lowest reaction scores and polypropylene lead to the highest rate of granuloma formation (Quesada et al. 1995). Evaluation of inflammatory reactions to polypropylene, polyglactin 910, and catgut and their role in adhesion formation showed that polypropylene had the lowest inflammatory score followed by polyglactin 910 and catgut, but no correlation to adhesion formation was found (Bakkum et al. 1995).
Suture reaction in bladder tissue has been evaluated to determine differences in inflammation and calculogenic potential. An early study showed that there was no difference in calcification around polyglycolic acid or chromic gut sutures in sterile or infected rat urine. The presence of infection did decrease the time that the suture remained within the bladder wall (Millroy 1976). When polydioxanone, polyglactin 910, and chromic gut were compared in bladder tissue, polydioxanone had the greatest initial inflammatory response, but there was no difference among groups at later time points. There was no difference in calculogenic potential between suture types over a 6 months period (Stewart et al. 1990). A similar study compared polydioxanone, polyglactin 910, and chromic gut and found that inflammation and stone formation were greater for chromic gut and polyglactin 910 compared to polydioxanone (Kosan et al. 2008).
Studies comparing suture materials in the gastrointestinal tract have also been performed. Using polyglycolic acid and catgut was compared in rat colonic anastomoses and found no difference in the degree of inflammation or strength of the anastomotic site (Munday and McGinn 1976). Another study comparing polyglactin 910 and polydioxanone in colonic anastomoses did not show any significant differences despite the belief that the multifilament nature of the polyglactin 910 in contaminated tissue could lead to more inflammation or abscess formation (Andersen et al. 1989). A third study evaluated polyglycolic acid, silk, polyglactin 910, chromic gut, polypropylene, and polydioxanone in wounds inoculated with bacteria commonly found in the colon. This study determined that monofilament absorbable sutures, with the exception of polydioxanone, lose strength too quickly and are not recommended for colonic surgery. In addition, braided materials led to prolonged inflammation and harbored bacteria (Durdey and Bucknall 1984).
Rabbits
Like rats, rabbits have been used
