Suture retention tests

Suture retention strength is given by the force required to pull a suture out of the prosthesis. The maximum force required (N) to pull the suture from the graft is measured using a mechanical tensile tester. The tests are generally conducted at 0° (parallel), 45° and 90° (perpendicular) to the longitudinal axis of the prosthesis to represent the different types of surgical end-to-end and end-to-side anastomoses that may be used to attach the device in vivo. The size and type of suture material may influence the results, so these variables should be recorded and reported with the results. In our laboratory we have found the use of size 0 to 3-0 stainless steel sutures provides reliable data. 

Apart from stiffness determination, other mechanical characterizations are required to quafify vascular grafts, including suture-retention strength and burst pressure testing. The suture-retention strength test aims at determining the force necessary to pull a... 

The prolonged retention of breaking strength of poly(p-dioxanone) suture is accompanied by a somew hat slow er rate of absorption than that reported for polyglactin 910 suture or polyglycolic acid suture. Poly(p-dioxanone) suture w as found to be essentially completely absorbed from the rat muscle by 180 days versus 60 to 90 days for polyglactin 910 and more than 120 days for polyglycolic acid suture, w hen similarly tested. 

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