The Authors carry out an experimental comparative study on four different suture materials (collagen cromic, polyglactin 910, PDS and nylon), used to perform end-to-end colonic anastomoses. They assess the resistence to the endoluminar pressure. The results show that during the first four days the anastomoses performed with PDS display a vere high resistence, while those with collagen cromic exhibit still lower value than Vicryl and nylon. After eleven days the anastomoses with the PDS show most resistence again, but the other three materials get similar value.