Catgut suture treatment produces roughly twice the stitch-holding time of plain catgut, but greater tissue inflammation occurs. Full tensile strength is extended to 18–21 days. It is brown rather than straw-colored, and has improved smoothness due to the dry presentation of the thread (plain catgut is wet). It is otherwise similar to plain catgut. Fast catgut suture is heat-treated to give even more rapid absorption in the body. The first known absorbable sutures were made of the intestines of sheep. The manufacturing process was similar to that of natural musical strings for violins and guitar, and also of natural strings for tennis
Strings (tennis) are strings that have more than one filament. They are most commonly made of many filaments of nylon, but can incorporate other materials such as polyurethane, Zyex, Vectran, Kevlar, and other materials. Multi-filament strings offer better elasticity than single filament strings, but usually inferior durability. No multi-filament string holds its tension as well as natural gut, and none of them is as soft. However, in comparison to mono-filament "synthetic gut", multi-filament strings can offer a much closer approximation of natural gut's performance. The softest multi-filament strings can be made with Zyex and polyolefin, although some of the softest of these