RESUMEN
This comparative, prospective, randomized tiral was made with the purpose of studying the techniques of handsewn suture, in one layer, seromuscular, interrupted stiches, with polyglatin 910 and the biofragmentable anastomotic ring in colorectal anastomosis below the peritoneal reflection. Forty-eight mongrel dogs were used, distributed in two groups of 24 animals. Each group was distributed in 3 subgroup. The subgroups were sacrificed on postoperative day 5, 15 and 30, repectively. The study evaluated mortality, morbidity, suture complications, macroscopic aspects, bursting strength, microscopic aspects and hydroxyproline concentration at the site of colorectal anastomosis. This analysis led to the the followin conclusions: There was no diference between anastomosis through macroscopic aspects, mortality and anastomotic leaks, fistula, stenosis and bleeding. The subgroups of animals with the biofragmentable anastomotic ring had on postoperative day 5 and 15 significant higher bursting when compared to the groups of handsewn technique at the same period. The subgroups of animals with the biofragmentable anastomotic ring had on postoperative day 15 and 30 significant less hydroxyproline concentration, when compared to the groups of handsewn rechnique at the same period. Both techniques of suture were valid and safe for low rectum anastomosis in dogs