Comparison of suturing techniques in the formation of collagen scaffold tubes for composite tubular organ tissue engineering.

In order to construct tubes for tissue engineering of composite tubular organs in the gastrointestinal tract, suturing techniques were investigated with regards to (a) type of suture material, (b) state of scaffold, (c) technical variations and (d) changes in scaffold morphology. Collagen scaffolds of 13 mm diameter and 3 mm thickness, in both dry and wet states, were sutured using braided and monofilament sutures. Four suture techniques were employed (a) continuous loop, (b) interrupted loops, (c) interrupted edge sutures and (d) continuous running edge suture. Scanning electron microscopic imaging was performed on the 4 tubes sutured. Monofilament sutures were used for tube formation as braided sutures were unsuitable. Dry scaffolds demonstrated tears during knot tying and fractures when bent around a stent. The interrupted and continuous running edge suture were the most suitable suturing techniques in wet scaffolds; further confirmed by scanning electron microscopy imaging. Our approach to tissue engineer segments of the gastrointestinal tract involves cell-seeding on scaffolds to permit attachment in vitro and later wrapping of scaffold layers of heterogeneous cells to create composite tissue. Scaffolds in wet state can be better sutured with monofilament materials using either the interrupted or running continuous edge suture technique.